Dissertations / Theses on the topic 'Civil engineering, n.e.c'
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Lilley, Ian David. "Acid fermentation of primary sludge at 20v C." Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/8295.
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Includes bibliography.Full scale studies on biological excess phosphrous removal plants have demonstrated the biological excess phosphorous removal can be increased by acid fermenting the settled sludge in the primary settling tank, and adding either the fermented sludge, or the acids elutriated from the sludge, to the influent of the biological phosphorous removal plant. Considerable uncertainty still exists, however, as to the mass of short chain fatty acids that can be generated and the degree of improvement in phosphorous removal that can be expected. This study was undertaken to (1) evaluate short chain fatty acid production in laboratory scale batch, single and in-series completely mixed reactor systems, (2) development of a model for acid fermentation, and (3) theoretically estimate the effect of acid addition on biological excess phosphorous removal.
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Vemulapati, Murali Krishna. "An extensible dynamic linker for C++." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/35462.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995.Includes bibliographical references (leaves 54-55).
by Murali Krishna Vemulapati.
M.S.
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Sinha, Sumit. "PARAMETER ESTIMATION AND AUTO-CALIBRATION FOR THE STREAM-C MODEL." MSSTATE, 2005. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04082005-151129/.
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The STREAMC model is based on the same algorithm as implemented by the Steady Riverine Environmental Assessment Model (STREAM), a mathematical model for the dissolved oxygen (DO) distribution in freshwater streams used by Mississippi Department of Environmental Quality (MDEQ). Typically the water quality models are calibrated manually. In some cases where some objective criterion can be identified to quantify a successful calibration, an auto calibration may be preferable to the manual calibration approach. The auto calibration may be particularly applicable to relatively simple analytical models such as the steady-state STREAMC model. Various techniques of parameter estimation were identified for the model. The model was then subjected to various techniques of parameter estimation identified and/or developed. The parameter estimates obtained by different techniques were tabulated and compared. A final recommendation regarding a preferable parameter estimation technique leading to the auto calibration of the STREAMC model was made.
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Appleton, Richard Joseph. "Corrosion fatigue of a C-Mn steel." Thesis, University of Glasgow, 1985. http://theses.gla.ac.uk/2176/.
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He, Jiliang. "Silyhydrazines : chemistry and pyrolytic conversion to Si-N-C ceramic materials." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29044.
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A new synthetic route to silylhydrazine molecules and polymers has been developed by the heterodehydrocoupling of organosilanes with hydrazines. A dimethyltitanocene catalyst has been employed to facilitate the dehydrocoupling reaction. The dehydrocoupling was shown to proceed by stepwise replacement of Si-H with hydrazino groups. The controlled hydrolysis of Ph$ sb2$Si(NHNHMe)$ sb2$ formed a hydrazinodisiloxane. Cyclizations of Ph$ sb2$Si(NHNHMe)$ sb2$ to form cyclic silylhydrazines were achieved by the reaction with n-BuLi/Ph$ sb2$SiCl$ sb2,$ or MeI (or HCl or Ph$ sb2$SiCl$ sb2),$ or thermolysis. Crystal structures of Ph$ sb2$Si(NHNR)(NRNH)SiPh$ sb2$ (R = H, Me) reveal chair (R = H) and twist-boat (R = Me) conformations of the Si$ sb2$N$ sb4$ ring, respectively. Planar and pyramidal nitrogen geometries were found to coexist in a hydrazino unit. A preceramic polymer, synthesized by the polymerization of MeHSiCl$ sb2$ with hydrazine in an appropriate ratio, was pyrolyzed to Si$ sb3$N$ sb4$/SiC$ rm sb{x}$N$ rm sb{y}$ in 67-80% ceramic yields. It is proposed that the structural unit of this polymer is a tetraazadisilacyclohexane bridged by MeHSi groups. This assignment is based on $ sp{1}$H and $ sp{29}$Si NMR measurements, as well as by comparison with the well-defined reaction product of Me$ sb2$Si(NHNH) $ sb2$SiMe$ sb2$ with MeHSiCl$ sb2.$ The pyrolysis was carried out from room temperature to 1500$ sp circ$C under argon and studied by using thermogravimetric analysis, solid-state $ sp{29}$Si NMR spectroscopy, infrared spectroscopy, x-ray powder diffraction, and elemental analysis. Serial structural changes were characterized in the pyrolyzed solid products. The ceramic product of this polymer at 1100$ sp circ$C was found to possess a quasi-metallic electrical conductivity ($ sigma$ = 10$ sp3$ ($ Omega$cm)$ sp{{-}1}),$ and was evaluated as an electrode material.
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Perkins, Eric David 1975. "Spatial reasoning for generalized N-body physics : discrete element algorithms." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80180.
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Spradbery, Charles. "The influence of thermal history on the hot ductility of Ti containing C Mn Al and C Mn Nb Al steels." Thesis, City University London, 2002. http://openaccess.city.ac.uk/7595/.
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A series of C-Mn-Al and C-Mn-Al-Nb steels having nominal composition 0.1 %C, 1.4%Mn, 0.3% Si and 0.005%N with Ti additions from 0 to 0.013% have had their hot ductility determined over the temperature range 700-1100°C. Tensile specimens were cast (melted) in situ and cooled at a rate of 100°C/min to the test temperature. They were subsequently strained to failure using a strain rate of 3x 10-3 s '. The influence of the addition of a 100°C undercooling step into the test cycle with a subsequent re-heat to the test temperature (at 500°C/min) was investigated. It has been shown that Ti additions, both to C-Mn-Al and C-Mn-Nb-Al steels impair hot ductility. Also, Nb containing steels give worse hot ductility with or without Ti additions for the steels examined. Thermal history was seen to have a small but significant effect on the hot ductility of steel. The addition of a 100°C undercooling step generally resulting in worse ductility due to additional precipitation of AIN and in the case of Nb containing steels probably both AIN and NbCN. TiN precipitation has been shown to have a more significant detrimental effect on hot ductility than AIN precipitation when one thermal cycle is introduced. Two regression equations have been obtained which may show that P is beneficial to ductility in Nb, Ti containing steels but detrimental to ductility in CMn-AI-Ti steels. Results have shown that increasing the test temperature (which will encourage coarser particles) generally leads to an increase in the dimple size and to better ductility. Interestingly, adding Ti to steels causes a larger dimple size to occur even though ductility deteriorates as the formation of TiN removes small AIN particles from solution. Thus the dimple size increases as it relates more and more to the presence of the larger MnS inclusions. The addition of an undercooling step in the test cycle reduces the dimple size in accordance with more precipitation taking place, most likely from AIN. During the work program it was discovered that there was potential for Ti to be lost should tensile samples be melted within silica tubes. Re-testing with an alumina based sheath ensured no Ti loss could occur.
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Bester, Andre. "Risiko-gebaseerde besluitondersteuning in siviele ingenieurswese: 'n metodologiese benadering tot verbeterende inligtingversameling en benutting." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/15934.
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356 Leaves printed single pages, preliminary pages i-xxii and numbered pages. Includes bibliography. List of tables, list of figures and abbreviations.Thesis (PhD)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT:Decisions affecting construction projects are often characterised by uncertainty. One of the sources of this uncertainty is the unit costs used in detail cost estimates. Analytical techniques are available to model these uncertainties, but information is required to quantify it. Historical data is the preferred source of information, but due to unavailability and unreliability it hampers the application of the analytical techniques. Changes in the construction environment necessitate the improvement of data sources and the utilisation thereof in a structured, comprehensive and integrated manner. The purpose of this study is to determine how decision-making can be improved by enhanced information capturing and usage of relevant data for improved cost calculations. This is achieved by investigating the various components of an information system, viz. dataflow, data source, data application, and shown how an integrated development of each of these components with processmodelling, database development and quantitative risk analysis can lead to improved decision-making. This is achieved by the conceptual redevelopment and development of information systems for decision support in two different construction environments, viz. road and dam construction, respectively. During the research it was found that processmodelling can contribute to the improvement of dataflow in the fragmented construction environment, but that shortcomings exist in the processmodelling tools. A method, based on set and graph theory, was developed to address it. It was also found that database development provides the opportunity to improve the quality of data stored in electronic format. A comprehensive database model to store all information relevant to construction costs, specifications and legal documents with the required error checking mechanisms was developed. The benefit of modelling the global uncertainty of project cost estimates with probabilistic techniques such as Monte Carlo simulation and the Limit State Cost Function, whilst including the effects of correlation, is also shown. The information gained from historical data-analysis, besides the application in the probabilistic techniques, was used to identify properties such as impact, variability and correlation. It was found in the study that a shortage of descriptive information, whether it be at project or item level, is predominately the source of variability in unit cost data after errors have been removed. In order to identify the information that would contribute to the lowering of variability a method was developed by using influence factors and unit cost correlation mechanisms to identify the most influential factors for data capturing. This led to the development of an ideal data-application model in which all the relevant data used in the different cost-estimation phases, viz. long term, conceptual and detail, would be captured and used. Based on what was found, a generic information system development model was proposed that indicated the interaction of all the aspects that were investigated. Two of the model’s foremost properties are its self-triggering process and incremental development (improvement). On top of this development model a development process was designed that can be used for the structured, comprehensive and integrated development/redevelopment of an information system for cost calculation.
AFRIKAANSE OPSOMMING:Besluite in konstruksieprojekte word gereeld gekenmerk deur onsekerheid. Een van die bronne van onsekerheid is die eenheidtariewe wat tydens detailkosteberekeninge gebruik word. Analitiese tegnieke is beskikbaar om die onsekerhede te modelleer. Inligting word egter benodig om die onsekerhede mee te kwantifiseer. Die voorkeur bron van inligting is historiese data, maar weens onbeskikbaarheid en lae akkuraatheid daarvan striem dit die aanwending van die analitiese tegnieke. Veranderde omstandighede in die konstruksiebedryf noodsaak egter die verbetering van databronne en aanwending daarvan op ’n gestruktureerde, omvattende en geïntegreerde wyse. Die doel van hierdie studie is om te bepaal hoe besluitneming verbeter kan word deur inligtingversameling en benutting van relevante data vir konstruksiekosteberekeninge te verbeter. Dit word gedoen deur die onderskeie aspekte wat deel vorm van ’n inligtingstelsel, nl. die datavloei, datastoring en aanwending te ondersoek en te toon hoe geïntegreerde ontwikkeling van elk van hierdie aspekte met behulp van prosesmodellering, databasisontwikkeling en kwantitatiewe risiko-analise, ’n bydrae kan maak tot verbeterde besluitneming. Dit word gedoen deur twee verskillende omgewings, nl. padbou en dambou, as moontlike toepassingsomgewings te gebruik vir onderskeidelik die herontwikkeling en ontwikkeling van so ’n inligtingstelsel vir besluitneming. Tydens die ondersoeke is dit gevind dat prosesmodellering ’n waardevolle bydrae kan lewer tot die verbetering van datavloei in die gefragmenteerde konstruksie-omgewing, maar dat tekortkominge in die modelleringsprogramme bestaan. ’n Metode, gebaseer op versameling- en grafiekteorie, is ontwikkel om hierdie aspekte aan te spreek. Dit is ook gevind dat databasisontwikkeling die geleentheid bied om die kwaliteit van elektronies gestoorde databronne te verbeter. ’n Datamodel wat omvattend genoeg is om al die inligting wat met konstruksiekoste, spesifisering en regsdokumente verbandhou te stoor, is ontwikkel met die nodige fout-onderskeppingsmeganismes. Die nut van probabilistiese tegnieke soos Monte Carlo-simulasie en die Limietstaat Kostefunksie om die globale onsekerheid van projekte se kosteberamings te modelleer en die effek van korrelasie op die resultate in ag te neem, is ook getoon. Die inligting afkomstig van historiese data-ontleding, naas die aanwending in die probabilistiese tegnieke, is gebruik om die eienskappe soos impak, veranderlikheid en korrelasiemeganismes, te bepaal. Dit is in die studie gevind dat ’n tekort aan beskrywende inligting, hetsy op projek- of itemvlak, die oorwegende bron van veranderlikheid is nadat foutiewe data verwyder is. Om egter die beskrywende inligting te bepaal wat ’n bydrae kan maak tot die verlaging van hierdie veranderlikheid is ’n metode ontwikkel met behulp van invloedfaktore en eenheidtariefkorrelasiemeganismes om die mees omvangryke faktore te bepaal vir onderskepping. Dit het aanleiding gegee tot die ontwikkeling van ’n ideale data-aanwendingmodel waarin al die relevante inligting vir die verskillende fases van kosteberekening, nl. langtermyn, konseptueel en detail, onderskep en gebruik word. Gebaseer op dit wat gevind is, is ’n generiese inligtingstelsel ontwikkelingmodel voorgestel wat die interaksie van al die aspekte wat ondersoek is ten opsigte van mekaar toon. Twee van die hoofkenmerke van hierdie model is die selfvoerende proses en die inkrementele ontwikkeling van die stelsel. Op hierdie ontwikkelingmodel is ’n ontwikkelingproses gebou wat gebruik kan word vir die gestruktureerde, omvattende en geïntegreerde ontwikkeling/herontwikkeling van ’n inligtingstelsel vir kosteberekeninge.
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McAvoy, Camille Z. "Palladium-catalyzed C-N cross-coupling reactions toward the synthesis of drug-like molecules." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73388.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Chemistry; and, (S.B.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. ).
The development of methodologies for C-N bond formation reactions is an important scientific challenge because of many academic and industrial applications. This work will focus particularly on palladium-catalyzed cross-couplings of amine-containing compounds with aryl halides. The scope of the BrettPhos precatalyst for the cross-coupling of ortho-substituted aryl iodides with amides is studied using substrates with a variety of functional groups. Due to potential metal-chelating issues with some of the substrates used in this study, a proposed ligand synthesis is discussed in which one of the methoxy groups of BrettPhos is replaced with a morpholine capable of occupying palladium's open coordination site during its catalytic cycle. A final C-N bond formation study focuses on the cross-coupling of aryl halides with amidine salts. For this cross-coupling, a methodology has been developed that can be applied to various electron-rich, electron-poor, and electron-neutral substrates. Furthermore, the products of this cross-coupling can be used for a subsequent electrocyclization through a reaction with aldehyde, demonstrating that a relatively simple two-pot methodology can be used to make relatively complex substrates with pharmaceutical applications. Both amides and amidines are common moieties in drug-like molecules because of the various biological activities of these functional groups. Potential medicinal applications of the developed cross-coupling of amidine salts with aryl halides methodology are described. Thus, methodologies for various palladium-catalyzed, C-N cross-couplings as well as a potential ligand synthesis to be used for palladium catalysis are herein discussed.
by Camille Z. McAvoy.
S.B.
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Tamtsia, Tamboue Basile-Honore. "The role of C-S-H microstructure and calcium hydroxide on creep and shrinkage of hardened portland cement paste." Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/6087.
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The thesis provides new research related to the mechanisms of creep and shrinkage of hardened Portland cement paste. The emphasis is put on the role of calcium silicate hydrate (C-S-H) microstructure and calcium hydroxide the most important phases in hydrated Portland cement paste. Specially designed specimens were used for creep and shrinkage measurements. These were well hydrated and very thin in order to avoid the occurrence of moisture gradients during the drying process. Length change of specimens following organic solvent exchange was used as a microstructural probe. Length change data of compacted CH powder, pre-conditioned from 11% to 85% relative humidity, are presented in order to support inferences on the role of CH in cement paste. Similar measurements were conducted on Portland cement and tri-calcium silicate pastes. It is suggested that the length change on removal of water may be related to surface energy changes not always specific to the C-S-H phase alone. Mass change measurements versus time during exchange were carried out to support the interpretation of the length change behavior. The re-saturation of Portland cement paste systems with synthetic pore solution after several drying pre-treatments was adopted to facilitate electrical measurements in order to investigate the shrinkage, creep, and creep recovery behavior. The state of the water in each pre-treated specimen was characterized using the DTGA methods. The coupling of a.c. impedance spectroscopy (ACIS) and creep and shrinkage measurements established ACIS as an effective method for evaluating pore structure modification as well as the nature of changes to the pore network of cement paste during creep and shrinkage experiments. Cement paste specimens from which all evaporable water was completely removed were found to creep a significant amount contrary to the hypothesis that they should not creep at all. The compacted calcium hydroxide specimens were found to creep with a creep coefficient less than one. This suggested that calcium hydroxide makes a contribution to the overall deformation of cement paste systems.
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Hoey, Thomas Michael. "Evaluation of high temperature performance of the Co-Cr-C coated P92 steel." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39989/.
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The motivation to increase the operation temperatures of fossil fuel power plant is primarily to improve power plant efficiency and reduce the negative environmental impact of fossil fuel power plant emissions. A main limitation to higher temperature operation is the enhanced oxidation damage of materials at increased temperatures. One of the most concerning areas of enhanced damage is on the inside surface of P92 ferritic steel (~ 9 % Cr) pipework which is used primarily to carry high temperature steam from the boiler. To combat the oxidation damage of P92 the energy industry has recently begun investigating the application of oxidation resistant coatings to P92 to enable higher temperature operation. Aluminium diffusion coatings have been the focus to date but they have been found to have a number of limitations, including coating degradation/porosity and a detrimental effect on the creep properties of the substrate, in part due to the high temperature coating process. Although other lower temperature coating methods, such as thermal spraying, have been considered these are limited by the practicalities and economics of spraying on the inside surface of P92 pipework. Therefore there is a real industrial need for consideration of a new coating type, for the inside of P92 pipework, which can be applied at low temperature and is also economical at full scale. This is where this thesis contributes by considering an electro-deposited Co-Cr-C coating never previously considered for this application. The Co-Cr-C type coating is electro-deposited to ~ 34-37 µm onto P92 ferritic steel. The coating is composed of ~ 35 wt % Cr3C2 electro-deposited within a cobalt matrix. The free-standing coating material and coated P92 system were subjected to isothermal oxidation in air and the oxidised state was characterised by a range of microstructural techniques. Oxidation behaviour, microstructural evolution and inter-diffusion between coating and substrate have all been considered. Thermo-Calc thermodynamic software has been used to make predictions about the long term evolution of the system. A series of uncoated and coated mechanical tests (creep, fatigue, creep-fatigue) have also been performed to assess the effect of coating application on the mechanical properties of P92 steel. This research has been motivated by industry at all stages and close collaboration has allowed for the most industrially relevant test conditions to be determined. Overall the Co-Cr-C coating is shown to be an industrially promising coating technology for application to P92. The study within this thesis shows that the good oxidation properties, interface behaviour and mechanical properties, combined with low temperature deposition and easy scale up, make this a viable coating for further development. It also has a number of advantages over the current aluminium coatings. The work within this thesis serves as a detailed feasibility and industry case study for further in-house testing by industrial sponsors, before future commercialisation of the product. A discussion of potential future work is also included at the end of the thesis.
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Pardo, Linda Hildegarde 1962. "Natural abundance of ¹⁵N as a tool for assessing patterns of nitrogen loss from forest ecosystems." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9311.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1999.Includes bibliographical references.
Stable isotopes provide an integrated measure of the nitrogen cycling history of a site. Among ecosystems with contrasting nitrate loss patterns, the [delta]15 N of soil and plant material should be higher at sites with higher nitrate losses. An underlying assumption in natural abundance isotope studies is that soil [delta]15 N is at steady-state over time. I found that [delta]15 N was not at steady state in either the Oie or Oa horizon for the period 1969 t[delta]1992 for the reference watershed (W6) at the Hubbard Brook Experimental Forest (HBEF); when nitrate losses were high, [delta]15 N increased. I measured the [delta]15N of soils from 28 soil pits at Watershed 5 at the HBEF before and after clear-cutting in order t[delta]test the hypothesis that elevated nitrification and nitrate loss induced by clear-cutting would be associated with a concurrent increase in soil [delta]15 N. A mass-balance model confirmed that increases in nitrification and nitrate loss after clear-cutting could explain the increase in soil [delta]15N (l .6%0 in the Oie horizon and 1. 1 o/o[delta]in the Oa horizon) in the organic horizons after 3 years. I tested the hypotheses: (1) that foliar [delta]15 N will be higher in a clear-cut watershed than in a reference watershed due t[delta]elevated nitrification and nitrate loss; and (2) that foliar [delta]1 5 N in a clear-cut watershed will track the rapid changes in streamwater nitrate after clear-cutting. Increased foliar [delta]15 N coincided with increased streamwater nitrate concentration, suggesting that the increased nitrification that caused elevated streamwater nitrate concentration als[delta]caused enrichment of the plant-available ammonium pool. Finally, I tested the hypotheses: (1) that [delta]15 N in soil and litter increases across a spatial gradient of nitrate loss, and (2) that [delta]15 N in soil and litter are elevated when nitrification potential is elevated. The enrichment factor, defined as [delta]15 N1foliar - [delta]15Nbs is a method of comparing [delta]15 N values from different sites by normalizing for the spatial heterogeneity in mineral soil [delta]15 N values. When net nitrification potential was high, the enrichment factor was higher, when nitrification potential was low, the enrichment factor was lower. The enrichment factor may prove valuable for comparing sites with different nitrogen cycling patterns.
by Linda Hildegarde Prado.
Ph.D.
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Camardo, Andrew T. "C-JUN N-TERMINAL KINASE INHIBITORY NANOTHERAPEUTICS FOR REGENERATIVE ELASTIC MATRIX REPAIR IN ABDOMINAL AORTIC ANEURYSMS." Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu1499868307678719.
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Sutar, Ajit Kumar 1976. "A web based integrated global project management system for large scale A/E/C/ projects." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9128.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.Includes bibliographical references (leaves 79-81).
The globalization of architecture, engineering and construction (A/E/C) industry has added new dimensions to project management. A wide spectrum of tools and software are used by project managers to manage these geographically distributed projects. PC or LAN based project management software is already widespread and popular in A/E/C industry. However, the access to the software is limited to the LAN and the server where they reside, and to use the software, project managers have to undergo extensive training. Current practice in collecting latest progress data for updating schedule is time consuming, and it is difficult to communicate this information to all the participants involved, especially if they are in different companies and located in different countries. The goal of this thesis is to develop an Integrated Web based Global Project Management System (IGPMS). IGPMS provides a web based graphical user interface that allows project managers to view and update the projects online. IGPMS provides project managers with web-based analysis and reporting tool for the project schedules. IGPMS also integrates the different information systems used for project management through software interoperability and provides a "common language" for product, process and resource information. IGPMS also introduces the concept of a web based project repository where project managers can submit a new project to the server and instantly view, update and analyze the project schedule through a web browser.
by Ajit Kumar Sutar.
S.M.
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Shi, Zhangsheng. "Strain engineering of Co-N-C catalyst toward enhancing the HER and ORR electrocatalytic activities." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/207078/8/Zhangsheng_Shi_Thesis.pdf.
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This thesis presents a comprehensive review of practical strategies to enhance the catalytic activity of M-N-C materials. The practical strategies can be extended to engineer external factors to break the linear scaling relationships and to further enhance the catalytic performances. In order to design the next-generation higher-performance catalysts, this project was a step forward in developing strain and heterostructure method to achieve a superior HER performance and a ORR performance beyond the limit.
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Dong, Jin Xiang 1961. "Effect of silicon on the kinetics of Nb(C,N) precipitation during the hot working of steels." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31048.
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The effect of Si on the kinetics of Nb(C,N) precipitation was investigated by using fractional softening measurements. Compression specimens, with diameters of 7.6 mm and lengths of 11.4 mm, were prepared from four Nb microalloyed steels containing a range of Si concentrations from 0.01 wt% to 0.41 wt%. The stress relaxation method was used in the beginning of this work, but the majority of the experimental results were derived from double-hit compression tests, with a strain of 0.3 applied to represent each pass at a strain rate of 0.1/sec. A solution heat treatment was applied immediately prior to each test.It was found that the rate of Nb(C,N) precipitation in hot deformed austenite increases with Si concentration. This phenomenon is attributed to the increases in both the Nb diffusivity and the activities of C and N that result from Si addition. Based on the Dutta and Sellars model, an expression for the effect of strain rate on the precipitation start time has been proposed. The present experimental results can then be extrapolated to mill conditions.
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Galenianou, Olympia. "Effects of adding wash tower effluent to Ano Liossia landfill to enhance bioreaction c by Olympia Galenianou." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34599.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.Includes bibliographical references (leaves 39-40).
A theoretical study was performed on the effects of adding sulfate-rich wash tower effluent from the Athens hospital waste incinerator to the Ano Liossia landfill of Athens. The method of mass balance was used to examine the production of leachate, the generation of methane, and the reduction of sulfates into sulfides. The water mass balance was performed using the method of Thornthwaite and the result indicated that the leachate collection facility at Ano Liossia landfill would be able to handle the additional leachate. The hydrocarbon-methane mass balance was performed using the EPA's LandGEM model which is based on first-order decomposition of the waste. A 26% difference between the generation of methane in a conventional landfill and a bioreactor landfill was predicted. Finally, a first-order model was developed by analogy to the LandGEM model to study the reduction reaction of sulfates into sulfides. The amount of hydrogen sulfide produced from solid waste disposed in the landfill dominated the amount of hydrogen sulfide produced from the additional wastewater.
M.Eng.
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Milhoranza, Mari?ngela Guerreiro. "As reformas do c?digo de processo civil e o direito intertemporal : rela??es entre tempo e direito (lei n? 8.455/1992 at? a lei n? 11.341/2006)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2007. http://tede2.pucrs.br/tede2/handle/tede/4011.
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Previous issue date: 2007-09-17A disserta??o tem por objetivo o exame das quest?es sobre Tempo e Direito no processo civil brasileiro. Para tanto, a pesquisa foi desenvolvida em tr?s cap?tulos. No primeiro cap?tulo, ? esbo?ada uma an?lise conceitual de Tempo, na perspectiva de fil?sofos como Santo Agostinho, Leibniz, Kant, Hegel, Heidegger. Ao t?rmino do primeiro cap?tulo, examinamos o conceito de conflito de leis no tempo e sua forma??o no direito brasileiro. Depois, no segundo cap?tulo, intentamos a an?lise dos efeitos produzidos na tens?o entre Tempo e Direito nas primeiras tr?s ondas de reformas do C?digo de Processo Civil. Na conclus?o clarificamos pontos de controv?rsia na pesquisa realizada
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Beşoğul, Ercan Supervisor :. Dikmen Toker İrem. "Reasons of delays in steel construction projects : an application of a delay analysis methodology \h [Electronic resource] / \c Ercan Beşoğul, Supervisor Assoc. Prof. Dr. İrem Dikmen Toker." Ankara : METU, 2006. http://etd.lib.metu.edu.tr/upload/12607159/index.pdf.
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Constantinides, Georgios 1978. "Invariant mechanical properties of calcium-silicate-hydrates (C-H-S) in cement-based materials : instrumented nanoindentation and microporomechanical modeling." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34377.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.Includes bibliographical references (p. 455-478).
Random porous solids such as bone and geomaterials exhibit a multiphase composite nature, characterized by water-filled pores of nm- to m-scale diameter. The natural synthesis and operating environments of such materials significantly alters phase composition and multiscale structural heterogeneities throughout the material lifetime, defining significant changes in macroscopic mechanical performance for applications ranging from multispan bridges to calcium-phosphate bone replacement cements. However, the nanoscale phases formed within the unique chemical environment of pores cannot be recapitulated ex situ in bulk form, and imaging of the composite microstructure is obfuscated by the size, environmental fragility, and nonconductive nature of such geomaterials and natural composites. Thus, there is an increasing drive to develop new approaches to image, quantify the mechanical contributions of, and understand the chemomechanical coupling of distinct phases in such composites. In this thesis, we utilize recent advances in experimentation namely instrumented indentation, and micromechanical modeling namely homogenization techniques, in an attempt to quantify the mutli-phase, multi-scale heterogeneity observed in all cement-based materials. We report a systematic framework for mechanically enabled imaging, measuring and modeling of structural evolution for cement based materials (CBM), porous geocomposites, at length scales on the order of constituent phase diameters (10-8 - 10-6 m), and thus identify two structurally distinct but compositionally similar phases heretofore hypothesized to exist.
(cont.) The presented experimental and modeling results culminated in micromechanical models for elasticity and strength that can predict the macroscopic mechanical behavior for a range of CBM systems. The models directly correlate the changes in chemical and mechanical state to predict the experimentally observed range of macroscopic mechanical properties. This general framework is equally applicable to other man-made and natural composites, and enables accurate prediction of natural composite microstructure and mechanical performance directly from knowledge of material composition.
by Georgios Constantinides
Ph.D.
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Nelson, Kyle Jeffery. "Formation of haloacetic acids and N-nitrosodimethylamine via the chlorination of carbon nanotubes." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1708.
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Recent investigations have shown that engineered nanomaterials such as carbon nanotubes (CNTs) are a source and precursor for disinfection byproduct (DBP) formation. The aim of this study was to extend previous research of CNTs by investigating the potential for other classes of CNTs to generate disinfection byproducts (DBP) during chlorination. We examined particular types of CNTs with surface groups analogous to suspected model precursors for DBP formation.Specifically, we conducted experiments to determine the formation of haloacetic acids (HAAs) and N-nitrosodimethylamine (NDMA) via the chlorination of carbon nanotubes.
Polymer coated CNTs generated the greatest total HAA concentration of up to 170 μg-HAA/mg-CNT. Results showed that the presence of surface oxide groups (e.g. surface carboxylic acid groups) promotes HAA formation. We observed a reasonably strong correlation between the extent of HAA formation and the concentration of surface oxygen on the CNT surface. Results also showed that CNTs behave similar to model precursors for di- and trichloroacetic acid formation (DCAA and TCAA, respectively).
Nitrogen containing CNTs have been shown as source of N-nitrosodimethylamine (NDMA). Surprisingly, CS PEG, which does not contain N, produces NDMA when reacted with ethylenediamine (EDA). Ultimately, EDA is contributing N to CS PEG by sorbing to the CNT surface, which is the likely source of N for NDMA formation. At lower EDA concentrations, NDMA production is limited by available EDA. Conversely, at higher EDA concentrations, NDMA production is limited by available chlorine that is in competition with EDA and the CNT surface.
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Allen, Tyler G. "A Study of the Variability Versus the Assumed Constancy of Manning's n." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/2802.
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Quantifying hydraulic roughness coefficients is commonly required in order to calculate flow rate in open channel applications. An assumption typically coupled with the use of Manning’s equation is that a roughness coefficient (n) that is solely dependent upon a boundary roughness characteristic (k) may be applied. Even though Manning reported unique values of n and x’ (the exponent of the hydraulic radius in Manning’s equation) for each of the different boundary roughness materials he tested, he chose x’ = 2/3 as representative, assumed a constant n value, and suggested that it was sufficiently accurate.
More recent studies have suggested that in addition to k; Rh, Se, and Fr can influence n. While research points to situations where n may vary, it is always a temptation to simply apply the constant n assumption especially in the case of more complicated channels such as composite channels where different roughness materials line different parts of a channel cross section.
This study evaluates the behavior of n as a function of Re, Rh, k, So, and Fr for four different boundary roughness materials ranging from smooth to relatively rough in a rectangular tilting flume. The results indicate that for the relatively rough materials n is best described by its relationship with Rh where it varies over a lower range of Rh but approaches and at a point maintains a constant value as Rh increases. The constant value of n is attributed to both the physically smooth boundary materials and a quasi-smooth flow condition in the rougher boundary materials. The study shows that an x’ = 2/3 (the basis of Manning’s equation) correlated to the assumption of a constant n value only applies to smooth boundary roughness materials and a quasi-smooth flow condition in the rougher boundary materials; otherwise, either n or x’ must vary.
These findings are then applied to compare 16 published composite channel relationships. The results identify the importance of applying a varying n where applicable due to the potential for error in assuming and applying a constant n. They also indicate that the more complicated predictive methods do not produce more accurate results than the simpler methods of which the most consistent is the Horton method.
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Svensson, Vilhelm, and Fredrik Tobler. "Utvärdering av olika metoder för stationsetablering med n-RTK." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27033.
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Fri stationsetablering med nätverks-RTK är en metod för att etablera en totalstation över en okänd punkt utan att ha tillgång till några kända punkter. Detta möjliggör för noggranna mätningar där stompunkter saknas. Det finns olika sätt att genomföra fri stationsetablering med n-RTK, och i denna studie utvärderades fyra olika sådana, där skillnaden mellan dem handlar om hur bakåtobjekten bestäms. De metoder som studerades var RUFRIS med 15 respektive 3 bakåtobjekt, Dubbelmätning och 180-sekundersmetoden. Vid RUFRIS mättes varje bakåtobjekt in med en observationstid på 5 s. Vid Dubbelmätning användes tre bakåtobjekt som var medeltal från två inmätningar vardera i 5 s med en tidsseparation på 30 min. Bakåtobjekten vid 180-sekundersmetoden var tre till antalet som mättes in med en observationstid på 180 s. Metoderna beskrivs bl.a. kortfattat i HMK – GNSS-baserad detaljmätning 2017 och ytterligare ett syfte med studien var att utvärdera beskrivningen utav dem däri. Med varje metod genomfördes tio etablering och efter varje sådan mättes en detaljpunkt in för att även undersöka hur noggranna inmätta detaljpunkter blev med de olika metoderna. Metoderna utvärderades genom att jämföra osäkerheter, RMS och användarvänlighet för etablerings- respektive detaljpunkter. Osäkerheterna var dels baserade på spridningen av tio etableringar/inmätningar per metod över en och samma punkt och dels sådana som presenterades i instrumentet vid varje etablering. För beräkning av RMS användes referenspunkter som mätts in genom statisk GNSS-mätning som efterberäknats i SWEPOS Beräkningstjänst. Förutom jämförelser mellan metoderna kontrollerades även om metoderna gav tillräckligt låga osäkerheter för att klara de rekommenderade toleranser för fri stationsetablering som anges i HMK – Terrester detaljmätning 2017. Beräknade osäkerheter i plan, alla metoder inräknat, varierade från 3 till 6 mm sett till både etablerings- och detaljpunkten vilket innebär att samtliga metoder klarar de högre toleranserna i HMK. Den metod som fick både lägst osäkerhet och RMS var RUFRIS med 15 bakåtobjekt, vilken dessutom var ensam om att vara tillräckligt noggrann för att klara de lägre toleranserna. Motsvarande osäkerheter i höjd varierade mellan 3 och 8 mm. Vad gäller toleranserna, visade sig endast RUFRIS med 15 bakåtobjekt vara lämplig, vid lägre krav. Vid högre krav fordras noggrannare metoder. Referenspunkterna hade för höga osäkerheter i förhållande till osäkerheterna hos de studerade metoderna, för att kunna utvärdera metoderna baserat på RMS, i den omfattning det var tänkt.Free station set up with network-RTK (n-RTK) is a method of establishing a total station over an unknown point without having access to any known points. This allows for accurate surveying even though control points are missing. There are different ways to perform free station set up with n-RTK, and in this study, four different methods were evaluated. The difference between the methods is how the target points are determined. The methods evaluated were RUFRIS (real time updated free station) with 15 and 3 target points, double measurement and the 180seconds method. With RUFRIS, each target point was measured with a 5 s observation time. In double measurement, three target points were used, where each target point was the average of two measurements. Each of these measurements used a 5 s observation time, and a 30 minute separation between the measurements. The number of target points in the 180-seconds method were also three, measured with an observation time of 180 s. The methods are briefly mentioned in HMK – GNSS-baserad detaljmätning 2017 and another purpose of the study was to evaluate the description of them in that document. With each method, ten establishments were performed and after each of them a detail point was surveyed to also analyze how accurate the different methods were in surveying. The methods were evaluated by comparing uncertainties, RMS and user-friendliness for establishments and detail points, between the respective methods. The uncertainties were on one hand based on the deviation of the ten establishments/detail points per method, each one made over the same point, and on the other hand based on the uncertainties presented by the instrument after each establishment. For calculation of RMS, reference points were used, which were measured by static GNSS, and then postprocessed in SWEPOS Beräkningstjänst. In addition to comparisons between the methods, they were also tested to see if they reached sufficiently low uncertainties to meet the recommended tolerances for free stationing, stated in HMK – Terrester detaljmätning 2017. Calculated planar uncertainties, all methods included, ranged from 3 to 6 mm for both the total station and the detail point, which means that all methods can handle the higher tolerances in HMK. The method with the lowest uncertainty and RMS was RUFRIS with 15 target points, which was also low enough to be able to cope with the lower tolerances. The uncertainties of the heights varied from 3 to 8 mm, in which RUFRIS with 15 target points was the only method precise enough to pass the higher tolerances. Another method with lower uncertainty is required when the higher tolerances for heights is specified. The chosen method for determining the reference points turned out to be too uncertain relative to the evaluated methods. Therefore RMS were not as appropriate for comparisons as planned.
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Skinner, Shaun N. "Study of a C-wing configuration for passive drag and load alleviation." Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/30778/.
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Non-planar wing configurations are often hypothesised as a means for improving the aerodynamic efficiency of large transport aircraft; C-wings may have the ability to exploit and unify drag reduction, aeroelasticity, and dynamics and control but their capacity to do so is ambiguous. The aim of this work is to provide an experimental demonstration with the aim of verifying the C-wing configuration’s potential application for drag and load alleviation. The successful application of a C-wing system for improving the aerodynamic efficiency depends upon the ability to construct the wing system such that a sufficiently low root bending moment and parasitic drag is maintained, relative to an equivalent planar wing system. This was facilitated by the development of a structured genetic algorithm (sGA) optimisation architecture capable of utilising fundamental aerodynamic theory, design specifications, and experimental facility constraints to provide non-arbitrary wing topology designs. The optimisation procedure aided in the design of a planar wing analogous of a typical mid-sized transport commercial aircraft wing topology, representing a 10% scale model. From this baseline design the sGA reconfigured the outboard 26% of the wing to independently form a C-wing topology, increasing the planforms aerodynamic efficiency by 74.5%. A modular wingtip semi-span model was designed to house the sGA planar and Cwing designs inside the University of Glasgow’s de Havilland wind tunnel for tests at Re = 1.5x10^6. A number of experimental techniques adopted, such as force/moment measurements, laser-Doppler vibrometry, PCB piezoelectric accelerometry, direct image correlation (DIC), surface flow visualizations, and stereoscopic particle image velocimetry (SPIV), provide insight into the semi-span model and wingtip arrangement structural dynamics and flow field physics. Aerodynamic performance metrics show that despite the C-wing operating with a 19.1% higher wing wetted area, a peak total drag reduction of 9.5% at a = 6^o is achieved in addition to a 1.1% reduction in the wing root bending moment for equivalent lift. Study of the near field wake indicated that this was achieved by the C-wing establishing a low vorticity spiral core vortex with accelerated vortex decay properties. The C-wing has also been found capable of passively attenuating buffet induced vibrations of the main-wing by up to 68.6%.
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Mangin, Steven F. "Development of an Equation Independent of Manning's Coefficient n for Depth Prediction in Partially-Filled Circular Culverts." Youngstown State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1284488143.
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Heukamp, Franz H. (Franz Hoyte) 1973. "Chemomechanics of calcium leaching of cement-based materials at different scales : the role of CH-dissolution and C-S-H degradation on strength and durability performance of materials and structures." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29282.
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Thesis (Ph. D .)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003.Includes bibliographical references (p. 327-341).
Calcium leaching is a durability threat for cement-based materials employed in critical infrastructures, such as Nuclear Waste Storage Systems. This thesis presents a comprehensive study of the material and structural consequences of calcium leaching on the strength and deformation behavior of cementitious materials. Starting from a three-level microstructural division of the heterogeneous microstructure of cement-based materials, a series of experimental and theoretical investigations is conducted leading to the development of a novel constitutive model and model-based simulations of the long-term mechanical performance of concrete structures subjected to calcium leaching. A chemically accelerated leaching device is developed using an ammonium nitrate solution to obtain asymptotically leached specimens in short times. An acceleration rate of 300 compared to natural leaching is obtained. The strength domain of leached cement pastes and mortars is evaluated through triaxial compression tests and uniaxial tension tests, revealing an important strength loss and an increased pressure sensitivity of the materials at failure, associated with leaching. A micromechanical approach for the homogenization of the elastic properties and the strength properties based on the three microstructural levels is developed. These developments allow estimating the relations between the microstructural changes and poroelastic properties including Biot-coefficient and Biot-modulus. In addition, upscaling schemes for the cohesion and friction properties on different levels of cement-based materials are developed.
(cont.) Through this the influence of the Interfacial Transition Zone on the strength of intact and leached materials is evaluated. The micromechanical elements of the analysis are combined in a chemoporoplastic constitutive model. The porosity created by calcium dissolution (chemical porosity) is identified as a state variable, relating dissolution process and mechanical properties. The model is implemented in a commercial finite-element program, and model-based simulations show the predictive capability of the developed approach to improve the durability design of concrete structures subjected to calcium leaching.
by Franz H. Heukamp.
Ph.D .
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Nichols, Gilbert. "Statistical Models of I-15 Bridge C-846: Changes in Natural Frequencies due to Temperature." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/5260.
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Structural Health monitoring is to determine the condition of a bridge based on instrument measurements. The C-846 Bridge in Salt Lake City has such instrumentation. The bridge is located in Salt Lake City at about 2100 South and Interstate 15. This bridge has two kinds of instruments on it: accelerometers and thermocouples. The accelerometers measure the vibrations of the bridge. The accelerometers have been recording data on the bridge since 2001. The thermocouples, which measure temperature, were added as part of this thesis in April 2016.
In light of recent research, damage may be detected from measuring the change in the natural frequency of a bridge, which can be obtained by manipulating the accelerometer data. However, the natural frequencies of a bridge change due to environmental effects, especially temperature. Temperature effects must be accounted for in order to better understand the damage.
The purpose of this research is not to detect damage. The bridge that is being monitored does not have any damage. The purpose of this study is to show how the dynamic properties of the C-846 Bridge in South Salt Lake City correlate with temperature. Additionally, several frequencies including the fundamental frequency of the bridge are identified.
It was found that the natural frequencies of the bridge increase with a decrease in temperature, and that the fundamental frequency of the bridge is 1.15 Hz.
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Bejarano, Roberto Villa. "An Investigation Into| I) Active Flow Control for Cold-Start Performance Enhancement of a Pump-Assisted, Capillary-Driven, Two-Phase Cooling Loop II) Surface Tension of n-Pentanol + Water, a Self-Rewetting Working Fluid, From 25 ?C to 85 ?C." Thesis, University of Nevada, Reno, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1565813.
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Cold-start performance enhancement of a pump-assisted, capillary-driven, two-phase cooling loop was attained using proportional integral and fuzzy logic controls to manage the boiling condition inside the evaporator. The surface tension of aqueous solutions of n-Pentanol, a self-rewetting fluid, was also investigated for enhancing heat transfer performance of capillary driven (passive) thermal devices was also studied. A proportional-integral control algorithm was used to regulate the boiling condition (from pool boiling to thin-film boiling) and backpressure in the evaporator during cold-start and low heat input conditions. Active flow control improved the thermal resistance at low heat inputs by 50% compared to the baseline (constant flow rate) case, while realizing a total pumping power savings of 56%. Temperature overshoot at start-up was mitigated combining fuzzy-logic with a proportional-integral controller. A constant evaporator surface temperature of 60°C with a variation of ±8°C during start-up was attained with evaporator thermal resistances as low as 0.10 cm2–K/W. The surface tension of aqueous solutions of n-Pentanol, a self-rewetting working fluid, as a function of concentration and temperature were also investigated. Self-rewetting working fluids are promising in two-phase heat transfer applications because they have the ability to passively drive additional working fluid towards the heated surface; thereby increasing the dryout limitations of the thermal device. Very little data is available in literature regarding the surface tension of these fluids due to the complexity involved in fluid handling, heating, and experimentation. Careful experiments were performed to investigate the surface tension of n-Pentanol + water. The concentration and temperature range investigated were from 0.25%wt. to1.8%wt and 25°C to 85°C, respectively.
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Sellgren, Felicia. "Gröna kvarter : En fallstudie om ekosystemtjänster för kvartersupprustning i Björkhagen." Thesis, KTH, Strategiska hållbarhetsstudier, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215689.
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Levens, Kurt Antony 1961. "Lighting a building with a single bulb : toward a system for illumination in the 21st c.; or, A centralized illumination system for the efficient decoupling and recovery of lighting related heat." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/68340.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.Includes bibliographical references (leaves 227-229).
Piping light represents the first tenable method for recovery and reutilization of lighting related heat. It can do this by preserving the energy generated at the lamp as radiative, departing from precedent and avoiding absorption of and re-emission of radiant heat as convection and conduction. Within thermodynamic limits, the radiant heat generated by an electric lamp or the sun is available for optical concentration and for reconstitution as a high thermodynamic quality power reservoir. Piping light from a large central lamp facilitates the decoupling of lighting related heat at the source, and also means that the efficiency of one central fixture can be stringently optimized instead of the multitude of fixtures it replaces in buildings. Luminous efficacy for a full-spectrum lamp decoupled of its infrared can be shown to approach theoretical limits of 250 lumens/watt. UV generated by the lamp, if coupled along with the illumination into the transport fibers, can be converted into visible radiation at the emitting end of the fiber, supplementing the light output. Fiber optics are used to carry information over long distances (actually encoded pulses of radiative IR), but certain fiber optics can carry tremendous amounts of energy. As fiber optics become more and more plentiful in telecommunications, their prices will come down. Cost and operating expense studies included in the final chapter of this thesis indicate that a large single source with light that is efficiently coupled and piped throughout a building's interior could reduce electric light consumption to one-fourth, and that even at current fiber pricing levels some systems can be competitive in initial cost to conventional lighting. Certain aspects of centralization suggest further reductions in cost and operating expenses such as centralized, instead of localized, relamping and cleaning, and eliminated requirements for thermal, electrical, and structural hardware at room fixture locations. The economic and technical feasibility of a central system depends on the simultaneous minimization of fiber aperture area and energy losses. Thermodynamically, the concentration of light for transport cannot surpass the energy density of the source. So such a system employs, at best, an optical process that preserves the extent of the source. That is, a high brightness source must be used to drive the system, regardless of the lamp's lumen output. High brightness lamps, then, can be viewed as an alternative to high efficacy lamps for increasing the energy performance of lighting systems in buildings. This thesis anticipates the existence of high brightness, high lumen lamps. The sun's 10,000 footcandles in peak conditions can be a potent contributor to the energy efficacy of buildings if a collection and utilization strategy is properly devised. At 100 sq. ft of available illumination for each sq. ft of collected sunlight, a scenario including simultaneous collection and distribution of electric light and heat and sunlight and solar heat in a building could reduce to near zero the energy consumed for lighting during peak sun conditions. Studies in this thesis indicate that an economically driven future role of solar energy in the lighting, heating, and cooling of buildings could very well revolve around keeping sunlight in the form of illumination and sunheat in the form of radiative heat, instead of converting both into electricity via photovoltaics and reconversion of this electricity back into electric light. Conventional lighting is an inefficient process, essentially using heat sources for the light they provide. Not only is lighting related electricity generating predominantly waste heat, this heat must be removed from the building's envelope by an additional input of energy. Even energy saving fluorescent lamps and fixtures produce at least 80% heat. This might serve to explain why 30% of the country's electricity is consumed by lighting. This thesis proposes a method for decoupling and recovery of lighting related heat, and transporting light in lieu of electricity to lighting fixtures (Chapters 2 and 6). Each of the optical components that would comprise such a system is examined. Chapter 7 investigates the radiation source. Chapter 8 develops the source reflector which will direct the source's radiative output in a particular direction. Chapter 9 studies a mirror that will separate the source's radiation beam into a light beam and a heat beam for subsequent processing. Chapter 10 looks at the heat collector that will convert the heat beam into a usable high-temperature power reservoir. Chapter 11 devises the light collector/ concentrator that will facilitate coupling of light energy into a fiber optic transport network. Chapter 12 assembles the constituent components into central modules. Chapter 5 surveys the light transport media, in particular fiber optics and Prism Optical Light Guide, for suitability to building lighting applications. The exact method of solar couplature is not introduced. Sample energy efficiency comparisons, cost and payback scenarios, implementation issues and concepts for room emitters are included in chapter 13. Related concepts for a transparent concentrating solar collector for use as a window or skylight, and a solar concentrating wall are disclosed in the conclusory chapter. Material included in this thesis has been patented by MIT. The usage of such material for any commercial means requires a licensing agreement.
by Kurt Antony Levens.
S.M.
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Rahil, Issam. "Elaboration et caractérisation de revêtements à base de nitrure de chrome, carbonitrure et carbure de titane élaborés par pulvérisation magnétron." Phd thesis, Ecole nationale supérieure d'arts et métiers - ENSAM, 2013. http://pastel.archives-ouvertes.fr/pastel-00967251.
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Le but de ce travail est d'élaborer de nouveaux revêtements anti-usure à base de nitrure de chrome, de carbure et de carbonitrure de titane par dépôt physique en phase vapeur afin d'améliorer la résistance à l'usure à sec des outils de coupe du bois.Des revêtements binaires de CrN et de MoN, ternaires de Cr-Mo-N et de Ti-W-C et quaternaires de Ti-W-C-N ont été déposés sur des outils de coupe en carbure de tungstène et en acier et sur des substrats de silicium par pulvérisation magnétron RF en utilisant différentes cibles (Cr, Mo, Ti et WC) sous différentes atmosphères (Ar, Ar + N2, Ar + CH4 et Ar + N2 + CH4).L'influence de la pression de travail, des ratios des gaz plasmagènes, des tensions d'auto-polarisation des cibles, de la température des substrats et de celle du recuit sur les propriétés des revêtements ont été étudiées, en utilisant l'EDS, la WDS, l'XPS, la DRX, le MEB, le MET, l'AFM, la microscopie optique, l'interférométrie optique (2D et 3D), le Scratch test, l'essai Daimler, la nanoindentation et la tribométrie alternative et rotative. L'objectif est d'établir une corrélation entre le comportement tribologique des revêtements étudiés et leurs propriétés physico-chimiques et mécaniques.Les revêtements optimaux présentant la meilleure résistance à l'usure à sec ont été testés en usinage de l'épinette noire à l'échelle industrielle dans des conditions sévères (-20/-25 °C). Les résultats montrent que grâce à l'emploi des revêtements de Cr-Mo-N, Ti-W-C et de Ti-W-C-N, la durée de vie des outils coupants a été augmentée de 47 à 77 % par rapport à l'outil non revêtu.Mots clés: revêtement, (Cr-Mo)N, (Ti-W)(C,N), propriétés physico-chimiques, propriétés mécaniques, comportement tribologique, usinage bois
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Viafore, Daniele. "As a??es repetitivas no direito brasileiro e a proposta de um incidente de resolu??o de demandas repetitivas no projeto de lei n? 8.046/2010." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2012. http://tede2.pucrs.br/tede2/handle/tede/4196.
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Previous issue date: 2012-08-27This work analyses the repetitive actions in brazilian law and a proposal of an incident of repetitive demands resolution, provided for the articles 930 to 941 of the new Civil Procedure Code Law project 8.046/2010, currently under discussion at the Chamber of Deputies. The economy of scale and speed of the commercial transactions through modern communications means made at the judiciary numbers high level of identical individual process. The lawsuit has suffered changes both quantitative, and qualitative. Forensic practice has detected real violations to the principle of due process in the treatment of repetitive actions, once the judiciary has proved inefficient for provide the judicial protection of effective form. Considering the majority of actions brought to the judiciary are repetitive, in which are discussion of questions of identical rights, so several procedural reforms and mechanisms of filters in order to reduce the volume of processes and resources, give speed in its processing and avoid the development of processes that have already been thoroughly valued by the Judiciary. However, it appears that the procedural reforms have not been sufficient to counteract the gloom. So, the Federal Senate opted for preparation of a new Code of Civil Procedure. With this intention and aiming to confer greater rationality judicial and reconcile vertically judicial decisions, it is proposed an incident resolution demand of repetitive. The proposal is to establish decision-paradigm with content of standard general and abstract spanning identical question of rights, whose implementation by judicial bodies competent is compulsory. The society is anxious for a procedural system that guarantees justice with efficiency and speed. In the current situation experienced by the Judiciary, the proposal of an incident of resolution of repetitive demands seems to be an instrument to print more uniformity and better rationality in judicial activity. The jurisdiction will not make it possible for the maintenance of different solutions to similar cases, which foster increased delay procedural and legal uncertainty. However, observing the extraprocedural factors that also contribute to the delay in the solution of legal disputes, such initiative can be taken as a contribution to the improvement in the performance of the judicial sector
Este trabalho tem por finalidade analisar as a??es repetitivas no Direito brasileiro e a proposta de um incidente de resolu??o de demandas repetitivas, prevista nos artigos 930 a 941 do Projeto de novo C?digo de Processo Civil - Projeto de Lei n? 8.046/2010, atualmente em tr?mite na C?mara dos Deputados. A economia de escala e a velocidade das transa??es comerciais, atrav?s dos meios de comunica??o modernos, produziram no Judici?rio n?meros elevados de lides individuais id?nticas. Os lit?gios sofreram mudan?as tanto quantitativas, quanto qualitativas. A pr?tica forense tem detectado verdadeiras viola??es ao princ?pio do devido processo legal no tratamento das a??es repetitivas, uma vez que o aparato judicial tem se revelado ineficiente para prestar a tutela jurisdicional de forma efetiva. Considerando-se que a maioria das a??es trazidas ao Judici?rio s?o repetitivas, em que se discutem quest?es de direito id?nticas, surgem, assim, diversas reformas processuais e mecanismos de filtros a fim de reduzir o volume de processos e recursos, conferir celeridade no seu processamento e evitar o desenvolvimento de processos que j? tenham sido, de forma exaustiva, apreciados pelo Judici?rio. Contudo, verifica-se que as reformas processuais n?o t?m sido suficientes para combater a morosidade. A par disso, o Senado Federal optou pela elabora??o de um novo C?digo de Processo Civil. Neste intento, visando conferir maior racionalidade judici?ria e compatibilizar verticalmente as decis?es judiciais, prop?e-se um incidente de resolu??o de demandas repetitivas. A proposta consiste em estabelecer decis?o-paradigma com conte?do de norma geral e abstrata abarcando id?ntica quest?o de direito, cuja aplica??o pelos ?rg?os judici?rios competentes revela-se compuls?ria. A sociedade anseia por um sistema processual que garanta a justi?a com efici?ncia e celeridade. Na atual conjuntura experimentada pelo Poder Judici?rio, a proposta de um incidente de resolu??o de demandas repetitivas parece constituir s?rio instrumento para imprimir maior uniformidade e melhor racionalidade na atividade jurisdicional. A jurisdi??o n?o se viabiliza pela manuten??o de solu??es diferentes para casos id?nticos, as quais ensejam maior delonga processual e inseguran?a jur?dica. Entretanto, atentando-se aos fatores extraprocessuais, que tamb?m contribuem para a demora na solu??o dos lit?gios judiciais, tal iniciativa pode ser tida como uma contribui??o para a melhoria do desempenho do setor judici?rio
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Morosini, Daniel. "Förväntad mätosäkerhet vid realtidsuppdaterad fri stationsetablering : En jämförelsestudie av olika fabrikat." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25453.
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Realtidsuppdaterad fri stationsetablering (RUFRIS) är en metod för att utföra geodetiska mätningar med totalstation. Metodiken bygger på fri station som använder bakåtobjekt skapade i realtid med Nätverks - Real Time Kinematic (N-RTK). Den praktiska användningen är gynnsam i olika verksamhetsområden och nödvändigheten att ajourhålla passiva stomnät och fixpunkter upphört. Syftet med denna studie är att utforska vad den förväntade mätosäkerheten är vid RUFRIS-etablering och detaljmätning med mätningsinstrument av fabrikaten Leica, Trimble och Topcon. Andra studier visar att ökat antal bakåtobjekt vid RUFRIS ger en minskad mätosäkerhet, vilket också testas i denna studie.Olika tidsintervall vid kontinuerlig datalagring för positionsbestämning av bakåtobjekt med N-RTK har använts, tidsintervallerna är 10, 60 och 180 sekunder. I kombination med olika antal bakåtobjekt har stationsetableringar och detaljmätning utförts. Antalet bakåtobjekt använda är 3, 5, 10/15 och 25. Koordinaterna från RUFRIS har kontrollerats mot referenspunkter skapade med långa GNSS-mätningar så kallad. statisk mätning med 4 timmar och 30 minuter lång observationstid. Rådata skickades in till SWEPOS-efterberäkningstjänst, för att få noggrant positionsbestämda referenspunkter i SWEREF 99 16 30 och RH 2000 referenssystem. I sin tur användes referenspunkterna för att avgöra hur stora avvikelser som erhålls vid RUFRIS.Mätosäkerheten vid stationsetablering är upp till cirka 40 mm i plan och höjd, beroende på längd av tidsintervall och antal bakåtobjekt, och god geometrisk spridning av bakåtobjekt upprätthålls. Mätosäkerheten i plan vid detaljmätning är ca 25 mm och ca 30 mm i höjd. Vid positionsbestämning i höjd gav 180 sekunder med få bakåtobjekt (3-5 st) en mindre avvikelse på ca 10 mm.Den största felkällan som påträffades är grova fel, dessa kan minimeras gengenom att kontrollera hur väl bestämda bakåtobjekten är skapade med N-RTK. Systematiska fel påträffades också och kan undvikas genom att hålla instrumenten servade och kalibrerade med jämna mellanrum.
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Ninfa, Alessandro. "Experimental analysis on the use of CCC systems to analyze the in-situ bearing capacity of C&D materials." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/6057/.
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Compaction is one of the most important processes in roadway construction. It is needed to achieve high quality and uniformity of pavement materials, which in turn better ensure long lasting performance.
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Johnson, Matthew H. "Analysis, design and fabrication of a frangible tower for use with sideband reference glide slope systems." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178308139.
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Cass, Roger. "A General Three Dimensional All Quadrilateral Surface Mesh Generation Algorithm." BYU ScholarsArchive, 1992. https://scholarsarchive.byu.edu/etd/3459.
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Among the available all-quadrilateral mesh generation algorithms progressive-front offers the best quality and robustness. The paving algorithm is a progressive-front technique that generates a two dimensional mesh of all quadrilaterals on planar surfaces. The technique is particularly suited to meshing irregular boundaries with interior holes. This thesis presents an extension of the paving algorithm to generalized three dimensional surfaces. The major problems in three-dimensional surface mesh generation are projection of nodes, calculation of interior angles, and connection of mesh fronts. The solutions to these problems are presented. This work is part of the ongoing CUBIT project at Sandia Labs. The application is written in object oriented style in C++. A description of object oriented programming is given, with the relative merits and drawbacks for engineering applications.
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Gelčys, Jurgis. "Gaisro temperatūrų poveikis apvalkalu sustiprintoms gelžbetoninėms konstrukcijoms." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080627_083925-21078.
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Baigiamajame magistro darbe nagrinėjamas gaisro temperatūrų poveikio vertinimas gelžbetoninėms konstrukcijoms. Aptariami standartinio ir natūralaus gaisro parametrai, skaičiavimo pagrindai, vertinimo kriterijai, bendrieji priešgaisrinio projektavimo reikalavimai, tikslai ir metodai. Analizuojamas gaisro poveikis betono ir armatūros mechaninėms, fizikinėms – cheminėms ir šiluminėms savybėms, temperatūros pokyčio įtaka bendram gelžbetonio darbui. Detaliai išnagrinėtas paprastasis skaičiavimo modelis standartinio gaisro veikiamų gelžbetoninių konstrukcijų laikomajai galiai vertinti, aptartos jo prielaidos. Pateikti 500 °C izotermės ir zonų skaičiavimo metodų principai, vertinimai. Išnagrinėti du analitiniai temperatūros pasiskirstymo betoniniame skerspjūvyje metodai, pateikti jų pavyzdžiai. Parodytas gelžbetoninių konstrukcijų projektavimo metodas pagal lentelių duomenis.
Tyrimui sumodeliuotas dviaukštis pastatas, kurio pirmame aukšte nagrinėjamas standartinio gaisro temperatūros poveikis ekscentri����kai gniuždomoms gelžbetoninėms kolonoms. Pastatas sumodeliuotas skaičiavimo programa STAAD Pro 2007 tam, kad gautume realias veikiančias apkrovas nagrinėjamiems konstrukciniams elementams. Skaičiavimai atlikti trims kolonoms, kurių paviršius yra skirtingai veikiamas gaisro temperatūros. Skaičiavimai atlikti pagal analitinio temperatūros sklidimo skerspjūvyje modelį bei pagal temperatūrinius laukus pagal EN 1992-1-2. Analogiškai įvertinamas gaisro poveikis gelžbetoniniu... [toliau žr. visą tekstą]This master thesis considers effect of fire temperatures on reinforced concrete structures. Parameters and mathematical characteristics of standard and natural fire, also objectives and methods of fire engineering is given. Mechanical, physical – chemical properties and behaviour of concrete and reinforcement separately and as composite structure analysed. Details and assumptions of simple calculation model stated. Principles of zone method (method of slices) and 500 °C izotherm (reduced section method) discussed. Two empirical methods examined for calculation of temperatures and heat rise in concrete element, presentation and examples is given. Design of reinforced concrete elements using tabulated data showned. Two – storey building designed using structural design and analysis software STAAD Pro. Building model is portrayed to obtain realistic loads on estimated elements. Calculations of fire resistance performed with three columns differently affected by temperature load. Fire design and analysis performed applying and comparing temperature fields received by calculation using empirical methods and charts given in EN 1992-1-2. Parallel analysis aplied on reinforced concrete columns strengthened with casing. Structure: introduction, literature review, research part, conclusions and suggestions, references. Thesis consist of: 96 p. text without appendixes, 84 pictures, 14 tables, 28 bibliographical entries.
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Johansson, Gutstav, and Rickard Johansson. "UTTORKNING AV HÅLDÄCKSELEMENT - En studie som jämför uttorkningsmöjligheterna för olika betongblandningar." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-74910.
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Håldäcksbjälklag är ett fördelaktigt bjälklagsalternativ på grund av dess många fördelar så som reducerad vikt och snabbt montage. Däremot har bland annat korta byggtider medfört att betongblandningar med lågt vct och hög andel cement efterfrågats av Strängbetongs kunder för att reducera risken för fuktproblematik, då en snabb uttorkning eftersträvas. Med en allt strängare och ambitiösare miljömålsättning har ett behov för att reducera andelen cement uppkommit. Vid en minskad cementmängd ökar således betongens vct vilket leder till en miljövänligare framställning samtidigt som en ekonomisk vinning erhålls. Syftet med undersökningen är därför att undersöka om olika betongblandningar med ett högre vct kan ersätta den nuvarande betongblandningen och samtidigt uppfylla förekommande uttorkningskrav. Detta skulle innebära fördelar för såväl producenterna som för beställarna. Betongen som undersökts i utredningen är av jordfuktig karaktär och är enbart avsedd för håldäckstillverkning. Uttorkningsprocessen som studeras motsvarar uttorkningen från tillverkning fram till montage. Fyra olika betongblandningar fördelade på tolv kuber kommer att undersökas i tre olika klimat och enbart uttorkningsmässiga skillnader mellan kuberna kommer att jämföras. Undersökningen baseras på mätdata som grundar på mätningar utförda av en auktoriserad fuktkonsult via Rådet för byggkompetens, RBK. Betongrecepten i utredningen har framtagits av Cementa. Litteraturstudier används även för att styrka påståenden och underlag som framkommer i rapporten. Resultatet från studien visar att de kuber som förvarats i inomhusklimatet och i klimatrummet har en linjär uttorkningsutveckling, till skillnad från kuberna som är placerade i utomhusklimatet som har en olinjär uttorkningsutveckling. I inomhusklimatet och i klimatrummet har kuberna med högre vct torkat ut mer än betongblandningarna med lägre vct (0,40 och 0,45), däremot är skillnaden i uttorkning minimal i kuberna som har förvarats utomhus. Den fastställda slutsatsen i undersökningen är att mer djupgående och längre mätstudier behövs för att säkerställa hur betonguttorkningen förändras i ett senare skede av uttorkningsprocessen.Hollow-deck joists are an advantageous flooring alternative because of its many advantages such as reduced weight and rapid assembly. However, among other things, short construction times have meant that concrete mixes with low w/c ratio and high proportion of cement have been requested by Strängbetongs customers in order to reduce the risk of moisture problems, when a rapid drying out pursued. With an increasingly stringent and ambitious environmental goal, a need to reduce the proportion of cement has arisen. With a reduced amount of cement, the w/c ratio of the concrete increases, which leads to a more environmentally friendly production, while at the same time an economic gain is obtained. The purpose of the study is therefore to investigate whether different concrete mixes with a higher w/c ratio can replace the current concrete mix and at the same time meet existing drying requirements. This would mean benefits for both the producers and orderers. The concrete that has been investigated in the investigation is of a soil-moist nature and is only intended for hole-deck production. The drying process that is studied corresponds to the dehydration from production to assembly. Four different concrete mixes divided into twelve cubes will be investigated in three different climates and only dehydration differences between the cubes will be compared. The survey is based on measurement data that are based on measurements performed by an authorized moisture consultant at Rådet för byggkompetens, RBK. The concrete recipes in the investigation have been developed by Cementa. Literature studies are also used to substantiate claims and supporting documents that appear in the report. The results from the study show that the cubes stored in the indoor climate and in the climate room have a linear dehydration development, unlike the cubes located in the outdoor climate that has a nonlinear dehydration development. In the indoor climate and in the climate room, the cubes with higher w/c ratio have dried out more than the concrete mixtures with lower w/c ratio (0,40 and 0,45), however, the difference in dehydration is minimal in the cubes that have been stored outdoors. The established conclusion in the study is that more in-depth and longer measurement studies are needed to ensure how concrete dehydration changes at a later stage of the drying process.
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Shohel, Muhammad Shah Newaz. "Panting Fatigue of Welded Steel Tee Details." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1428328220.
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Upadhyaya, Ashraya. "Nitrogen Doped Titanium Dioxide in the Photocatalytic Degradation of Methylene Blue." ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/honors_theses/120.
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Titanium dioxide(TiO2) is a stable, effective and well-known photocatalyst for degradation of pollutants. However, its practical applications are limited due to the need for energy higher than 3.2 eV, or a wavelength lower than 390 nm (high frequency waves, ultraviolet and above) hindering its ability to effectively work in the visible light region (about 400 nm to 700 nm). Nitrogen-doped TiO2 (N-TiO2) has garnered some attention as a photocatalyst as it appears to work even in the visible light region. This could allow the utilization of a larger part of the solar spectrum. This thesis presents the results of photocatalytic degradation of methylene blue (MB) carried out under simulated visible light by using TiO2 and N-TiO2(doped in the lab) to evaluate and compare their efficiencies under similar conditions.
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Beck, Lisa Elanna. "Diffusivity and resistance to deterioration from freezing and thawing of binary and ternary concrete mixture blends." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8784.
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Master of ScienceDepartment of Civil Engineering
Kyle Riding
Corrosion of reinforcing steel is one of the most common and serious causes of reinforced concrete deterioration. While corrosion is normally inhibited by a passive layer that develops around the reinforcing steel due to the high pH environment of the surrounding concrete, chlorides will break down this protective layer, leading to reinforcement corrosion. Decreasing the diffusivity of the concrete would slow the ingress of chlorides into concrete, and is one of the most economical ways to increase the concrete service life. Optimized concrete mixtures blending portland cement and supplementary cementing materials (SCMs) have become popular throughout the construction industry as a method of improving both fresh and long-term concrete properties such as workability, strength and porosity. It has been shown that use of Class F fly ash, silica fume and ground granulated blast furnace slag (GGBFS) in binary concrete mixture blends can result in a significant reduction in concrete diffusivity. This study investigates the ability of Class C fly ash and ternary concrete mixture blends to also aid in diffusivity reduction. In order to study the effect of incorporation of SCMs into concrete, mixtures containing Class C and Class F fly ash, silica fume and GGBFS were tested following the ASTM C 1556 procedures to measure the concrete’s apparent chloride diffusivity. Structure life cycles were modeled using the measured apparent chloride diffusivities with two finite-difference based life-cycle analysis software packages. To determine whether a correlation between diffusivity and deterioration due to freezing and thawing exists, samples were also tested for their ability to resist deterioration from freezing and thawing cycles using a modified ASTM C 666 Procedure B test. Results show that the use of Class C fly ash yields some service life improvements as compared to the portland cement control mixtures, while ternary mixture blends performed significantly better than the control mixture and equal to or better than the binary SCM mixtures tested. Freeze-thaw tests showed all mixtures to be equally resistant to deterioration due to freezing and thawing.
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Matheus, Antonio Carlos Motta. "Modelo de gerenciamento de resíduos de construção civil utilizando o Balanced Scorecard (BSC): contribuições para uma efetiva prática." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7748.
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O gerenciamento dos resíduos de construção civil configura-se ferramenta
sistêmica, no qual se verifica a possibilidade do uso de um modelo de Sistema de
Gerenciamento com a utilização de indicadores. O referencial teórico abordado, com
conceitos e entendimentos sobre a responsabilidade socioambiental das
organizações na disposição correta de seus resíduos, particularmente aqueles
oriundos de construção civil como indutores e indicadores de responsabilidade social
e ambiental, posicionamento estratégico e a responsabilidade socioambiental,
delimitam a esfera financeira como um ativo intangível da empresa. Assim, o
Balanced Scorecard, apresentado em suas quatro perspectivas: a financeira, a do
cliente, a dos processos internos e a do aprendizado e crescimento, relacionam-se
com a responsabilidade na gestão dos seus resíduos. Para avaliar a adequação dos
indicadores e respectivas métricas, torna-se plausível a aplicação dos dez testes do
Performance Prism. A gestão por indicadores é assim analisada na ótica das
diferentes, porém integradas, perspectivas do Balanced Scorecard. A principal
característica do modelo em estudo é a inserção da responsabilidade pelos resíduos
às estratégias empresariais, conduzindo linearmente tais ações aos princípios da
empresa. Os resultados apresentados após sua implementação em uma empresa
de engenharia civil proporcionaram um reaproveitamento do entulho gerado da
ordem de aproximados 52% como matéria-prima para agregados, comprovando a
viabilidade de uso dos indicadores, integrando as ações de gerenciamento de
resíduos às demais questões críticas e estratégicas da empresa.
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Idri, Amanda C. "Development of a Correlation Equation Between Shear Wave Values And NSPT Values in Northeastern Ohio." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1574441753941474.
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Dowd, Garrett E. "Improving Autonomous Vehicle Safety using Communicationsand Unmanned Aerial Vehicles." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574861007798385.
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Nasanen, Liisa Maria Elina. "Stabilisation of archaeological copper alloy artefacts using subcritical fluid technology." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/114466/.
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The research presented aimed to investigate potential of subcritical fluid technology to effect Cl- release and transform compounds of copper alloy artefacts of cultural significance. The work intended to determine the most effective pH, temperature, and time combination subcritical treatment variables to: 1. transform or solvate insoluble or sparingly soluble copper compounds containing Cl - CuCl and Cu2(OH)3Cl (atacamite and clinoatacamite); 2. examine impact on typical patina compounds Cu2O and Cu2CO3(OH)2 and to establish optimal conditions for their retention throughout treatment. Additionally, the research expected to offer guidance on the values of the operational parameters to use when applying subcritical treatment to archaeological copper alloy objects. The series of experiments yielded preliminary results on solvation, extraction, chemical transformation, and physical modification of the predominant corrosion products found on copper alloy artefacts. Experiments were completed using analogue pressed pellets of corrosion products, naturally corroded copper coupons and archaeological artefacts, with specific focus on corrosion profiles, metallography and microstructure. The results of extraction show significant amounts of Cl- are removed and thus the reactivity of objects is reduced. While this study conclusively demonstrated subcritical treatment is capable of both removal and transformation of Cl-bearing compounds commonly present in copper alloy objects, it cannot be recommended for treating archaeological objects based on these results alone. Aesthetic and physical changes are unpredictable and may be unacceptable. Accepting these changes cannot directly be balanced against the proven effectiveness of subcritical treatment for removing Cl, nor its rapid treatment time.
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Persson, Herman, and Alexandru Zamfir. "Uttorkning av betong i nyproduktion." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-97204.
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Under de senaste åren har tillverkningsprocessen av betong genomgått en förändring föratt göra materialet och processer mer miljövänliga. Detta är en följd av att betong räknasvara ett av de viktigaste byggnadsmaterialen i världen. En viktig anledning till denomfattande användningen av betong är att betong som material är fuktbeständigt, att detinte möglar och att det är väldigt formbart.Förenta nationerna nämner 17 globala mål vars uppgift är att främja hållbarhet i framtidendär mål nio anger ”Bygga upp en motståndskraftig infrastruktur, verka för eninkluderande och hållbar industrialisering och främja innovation”. Detta faktum måstenaturligtvis tas hänsyn till även vid tillverkningen av betong och dess beståndsdelar.Syftet med det här examensarbetet är att med hjälp av ett stort antal mätpunkter visa påolika styrkor och svagheter inom tre olika typer av prognostiserande beräkningsverktygav torkningstider. Målet med arbetet är att jämföra statistik av praktiska mätningar,utfärdade av Conservator AB, med varandra och med de tre vanligasteberäkningsprogrammen som används för att beräkna uttorkningstider av betong.I de undersökta byggdelarna i arbetet gav TorkaS den högsta noggrannheten och sedanföljt väldigt nära av PPB. Utöver detta uppfyller de förväntningar som borde kunna ställaspå prognostisering av uttorkningstid för betong. Studien har också visat attuttorkningstiden för betong i nyproduktion påverkas mest av uttorkningsklimatet och tjockleken på avjämningsmassan.In the recent years, the manufacturing of concrete has undergone a change to make theprocesses and the material more environmentally friendly. This is accompanied by thefact that concrete is one of the most important building materials in the world. This islargely because concrete as a material is moisture resistant, does not mold and is highlyformable.The United Nations mentions 17 global goals whose mission is to promote sustainabilityin the future whereas the ninth one states that “Build resilient infrastructure, promoteinclusive and sustainable industrialization and foster innovation”. This leads to the factthat it needs to take in consideration the manufacturing of concrete and its components.The purpose of this research is to show strengths and weaknesses in prediction tools forconcretes drying time by comparison with data from many measuring points. Besidesthat, the aim is to compare statistics of practical measurements, which were issued byConservator AB, with each other and with other three most commonly used programs inforecasting the drying time for concrete, i.e. TorkaS, BI-Dry and PPB.From the building sections that were researched, TorkaS gave the highest accuracy inforecasting the drying time and then followed very closely by PPB. In addition, BI-Drydid not meet the expected requirements on some of the building sections. Besides that, thestudy has shown that the drying time of concrete in new production is most influenced bythe drying climate and the thickness of the compound.
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Soboh, Yousef. "Anaerobic Co-Digestion of Algal Biomass and a Supplemental Carbon Source Material to Produce Methane." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4485.
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Algae that are grown in wastewater treatment lagoons could be an important substrate for biofuel production; however, the low C/N ratio of algae is not conducive to anaerobic digestion of algae with economically attractive methane production rates. Increasing the C/N ratio in anaerobic, laboratory scale, batch reactors by blending algal biomass with sodium acetate resulted i increased methane production rates as the C/N ratio increased. The highest amount of methane was produced when the C/N was 21/1. When the C/N was 24/1, the biogas production rate decreased. Batch experiments were done to evaluate the effect of optimizing the C/N ratio on methane production from algae and to identify the most essential information needed to conduct research on co-digestion of algal biomass using the continuous, high-rate, up-flow anaerobic sludge blanket (UASB) reactor system. Based on the results obtained from batch reactor experiments, anaerobic co-digestion of algal biomass, obtained by continuous centrifugation from the Logan City, Utah, 5th stage wastewater treatment lagoon, and sodium acetate was conducted using laboratory scale UASB reactors with the C/N ratio in the feedstock adjusted to 21/1. Duplicate, 34 L UASB reactor systems were built of poly(methyl methacrylate). Both reactors were seeded with 11 L of anaerobic sediment from the 3rd stage lagoon. The pH of the feedstock was adjusted to the neutral range. The feedstock was initially introduced at a low organic loading rate of 0.9 g/L.d with a hydraulic retention time (HRT) of 7.2 days and then increased up to 5.4 g/L.d and a HRT of 5.5 days. These organic loading rates corresponded to an initial influent chemical oxygen demand (COD) of 6.25 g/L and increased to 27.2 g/L. Methane production increased from 270 mL/g to 349 mL/g COD biodegraded. COD removal efficiency was 80% and biogas methane composition was 90% at steady state. Algal biomass contributed 33-50% of the COD in the feed stock depending on the COD of the algae paste from centrifugation. The shortest HRT at which steady state was not affected was 5.5 days. At lower HRT all monitored parameters showed a slight decrease after the 75th day of operation.
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Ramalho, Breno Da Silva. "Licenciamento ambiental em áreas militares: proposta de método para a conformidade ambiental de um posto de abastecimento de combustível." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2947.
Full textAbstract:
O Exército Brasileiro tem entre suas atribuições o permanente preparo de sua tropa, visando sua melhoria operacional, pronto emprego e a utilização responsável do meio ambiente sob sua responsabilidade. A Lei Complementar nº 140/2011, atribuiu às Forças Armadas a dispensa do licenciamento ambiental de empreendimentos e atividades que envolvam o preparo e emprego da tropa. Desta forma, surge a necessidade de elaboração de procedimentos que conciliem a atividade militar com a conformidade ambiental. Através de um estudo de caso, esta pesquisa analisou, descreveu e criticou os procedimentos realizados pelos órgãos ambientais, necessários ao licenciamento ambiental para um posto de abastecimento de combustível de veículos automotores. Foi proposto método a ser aplicado pela Diretoria de Meio Ambiente do Exército Brasileiro para verificação da conformidade ambiental de seus futuros empreendimentos. O método proposto é dividido em duas fases, a primeira chamada de licenciamento de 1ª Fase, e a segunda, de licenciamento de 2ª Fase, com a previsão da renovação da 2ª Fase. Foram criados formulários para cada fase do licenciamento, bem como roteiros de fiscalização de tanques de armazenamento e tubulações. Como resultado da aplicação do método, propôs-se uma minuta de Instrução Normativa, que se adotada irá padronizar a conformidade ambiental para aquela atividade dentro do Exército Brasileiro. Ao se analisar os processos administrativos dentro do Exército Brasileiro pode-se concluir que não há procedimentos específicos que tratem de forma administrativa ou técnica o licenciamento ambiental de um posto de abastecimento de combustível. Concluiuse que 58 % dos quesitos poderiam ser suprimidos, sem prejuízo do processo de licenciamento. Pode-se perceber como vantagens da aplicação do método: a economia de tempo e recursos financeiros decorrentes da maior rapidez do rito proposto em comparação ao licenciamento tradicional, a conformidade ambiental da atividade de abastecimento dentro do escopo da atividade militar e, sob a ótica administrativa, a padronização do licenciamento ambiental. Como desvantagem conclui-se que o autolicenciamento pode propiciar desvios de conduta no interesse institucional, os quais podem ensejar a não conformidade ambiental, almejada pelo método, tais falhas administrativas precisam ser verificadas e combatidas por meio de efetiva fiscalização por parte de órgãos externos ao Exército Brasileiro ou através da fiscalização cruzada isto é, a verificação do processo da conformidade ambiental realizado por uma Força Armada diferente da que realizou o processo, ou seja o Exército Brasileiro fiscalizaria os processos de licenciamento feitos pela Marinha do Brasil e Aeronáutica, sendo a recíproca verdadeira. Outra desvantagem é a necessidade de alocação de recursos humanos adicionais para aplicação do método, necessitando de um aperfeiçoamento constante de seus militares.The Brazilian Army has among its attributions the permanent preparation of its troops, aiming at its operational improvement, ready employment and responsible use of the environment under its responsibility. Complementary Law No. 140/2011, assigned to the Armed Forces the exemption of the environmental licensing of undertakings and activities that involve the preparation and employment of the troops. In this way, the need arises to elaborate procedures that reconcile military activity with environmental compliance. Through a case study, this research analyzed, described and criticized the procedures performed by the environmental agencies, necessary for the environmental licensing for a fuel supply station of automotive vehicles. A method was proposed to be applied by the Brazilian Army's Environment Directorate to verify the environmental compliance of its future projects. The proposed method is divided into two phases, the first licensing call for Phase 1, and the second, for Phase 2 licensing, with the expected Phase 2 renewal. Forms have been created for each phase of the licensing, as well as inspection scripts for storage tanks and pipelines. As a result of the application of the method, it was proposed a draft Normative Instruction, which if adopted will standardize the environmental compliance for that activity within the Brazilian Army. When analyzing the administrative processes within the Brazilian Army it can be concluded that there are no specific procedures that deal with the environmental licensing of a fuel supply station in an administrative or technical way. It was concluded that 58% of the items could be deleted, without prejudice to the licensing rite. The advantages of applying the method can be perceived as: the saving of time and financial resources resulting from the increased speed of the proposed rite compared to traditional licensing, environmental compliance of the supply activity within the scope of military activity and, from the administrative point of view , the standardization of environmental licensing. As a disadvantage, it can be concluded that self-certification may lead to deviations of conduct in the institutional interest, which may lead to environmental non-compliance, as desired by the method, such administrative failures must be verified and countered by effective oversight by external bodies. Brazilian Army or through cross-inspection, ie the verification of the environmental compliance process carried out by a different Armed Forces from the one that carried out the process, ie The Brazilian Army would supervise the licensing processes carried out by the Brazilian Navy and Aeronautics, being the reciprocal true. Another disadvantage is the need to allocate additional human resources to implement the method, requiring a constant improvement of its military.
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Roper, Matthew B. "Evaluation of Laboratory Durability Tests for Stabilized Aggregate Base Materials." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/902.
Full textAbstract:
The Portland Cement Association commissioned a research project at Brigham Young University to compare selected laboratory durability tests available for assessing stabilized aggregate base materials. The laboratory research associated with this project involved two granular base materials, three stabilizers at three concentration levels each, and three durability tests in a full-factorial experimental design. The granular base materials consisted of an aggregate-reclaimed asphalt pavement blend obtained from Interstate 84 (I-84) and a crushed limestone obtained from U.S. Highway 91 (US-91), while the three stabilizer types included Class C fly ash, lime-fly ash, and Type I/II Portland cement. Specimens were tested for durability using the freeze-thaw test, the vacuum saturation test, and the tube suction test. Analyses of the test results indicated that the unconfined compressive strength (UCS) and retained UCS were higher for specimens tested in freeze-thaw cycling than the corresponding values associated with vacuum saturation testing. This observation suggests that the vacuum saturation test is more severe than the freeze-thaw test for materials similar to those evaluated in this research. The analyses also indicated that the I-84 material retained more strength during freeze-thaw cycling and vacuum saturation and exhibited lower final dielectric values during tube suction testing than the US-91 material. Although the I-84 material performed better than the US-91 material, the I-84 material required higher stabilizer concentrations to reach the target 7-day UCS values specified in this research. After freeze-thaw testing, the Class C fly-treated specimens were significantly stronger than both lime-fly ash- and cement-treated specimens. In the vacuum saturation test, none of the three stabilizer types were significantly different from each other with respect to either UCS or retained UCS. Dielectric values measured during tube suction testing were lowest for cement-treated specimens, indicating that cement performed better than other stabilizers in reducing the moisture/frost susceptibility of the treated materials. The results also show that, as the stabilizer concentration level increased from low to high, specimens performed better in nearly all cases. A strong correlation was identified between UCS after the freeze-thaw test and UCS after the vacuum saturation test, while very weak correlations were observed between the final dielectric value after tube suction testing and all other response variables. Differences in variability between test results were determined to be statistically insignificant. Engineers interested in specifying a comparatively severe laboratory durability test should consider vacuum saturation testing for specimens treated with stabilizers similar to those evaluated in this research. The vacuum saturation test is superior to both the freeze-thaw and tube suction tests because of the shorter duration and lack of a need for daily specimen monitoring. Although the Class C fly ash used in this research performed well, further investigation of various sources of Class C fly ash is recommended because of the variability inherent in that material. Similar research should be performed on subgrade soils, which are also routinely stabilized in pavement construction. Research related to long-term field performance of stabilized materials should be conducted to develop appropriate thresholds for laboratory UCS values in conjunction with vacuum saturation testing.
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Pape, Marion. "Frauen schreiben Krieg." Doctoral thesis, Humboldt-Universität zu Berlin, Philosophische Fakultät III, 2007. http://dx.doi.org/10.18452/15584.
Full textAbstract:
Kein anderes Thema hat die nigerianische Literatur so dominiert wie der nigerianische Bürgerkrieg, in dessen Verarbeitung sich verstärkt auch Autorinnen einmischen. Die Dissertation evaluiert 34 Texte von 16 nigerianischen Autorinnen - 12 Romane und 22 Kurzgeschichten - und analysiert sie als Gesamtkorpus, in dem die Texte miteinander und mit der Männerliteratur einen Dialog um den Bürgerkrieg führen. Die Autorinnen wenden bei ihrem "war talk" literarische Strategien wie "re-reading" und "re-writing" an, das Neu-Lesen, Fort- und Umschreiben der Texte und Diskurse des "Zentrums", durch die nicht nur die Blindstellen eines von Männern dominierten literarischen Diskurses sichtbar werden, sondern durch die auch der Prozess des Aushandelns der Geschlechterverhältnisse sowie des Krieges selbst erfolgt, seiner Ursachen, Auslöser und Folgen. Die Autorinnen stellen den Krieg als "sexuelle Unordnung" dar, als Geschlechterkrieg. Die Untersuchung zeigt, dass bei der Verortung der Perspektive der Autorinnen neben Geschlecht, ethnischer Zugehörigkeit auch andere Faktoren, wie Alter, Race, Grad der Distanz oder Nähe etc. berücksichtigt werden müssen, um vorschnelle Festschreibungen zu vermeiden. Hierbei spielen die Paratexte eine wichtige Rolle, in denen die Autorinnen sich persönlich zum Krieg äußern. Die Arbeit bewegt sich an den Schnittstellen mehrerer Disziplinen: Literatur, Historiographie und Geschlechterstudien. In der Einleitung werden die theoretischen Prämissen im Kontext von Krieg, Geschlecht und literarischer Repäsentation behandelt. Das 1. Kapitel ist dem historischen Kontext des Bürgerkrieges, einschließlich der Rolle der Frauen darin gewidmet. Im 2. Kapitel geht es um die Darstellung des Krieges, des Selbst- und Feindbildes sowie der Zukunft. Das dritte Kapitel handelt von der Beziehung zwischen Bürger- und Geschlechterkrieg, vermittelt durch das Medium literarischer Text. Die Zusammenfassung der Ergebnisse und der Ausblick auf zukünftige Forschung erfolgt im Schlussteil. Der Anhang enthält ein vorläufiges Verzeichnis der gesamten Frauenliteratur über den nigerianischen Bürgerkrieg.No other topic has dominated the Nigerian literature as much as the Nigerian Civil War and female authors increasingly interfere in its literary representation. The thesis evaluates 34 literary texts by 16 female Nigerian authors - 12 novels and 22 short stories - and analyses them as distinctive corpus whose individual texts are in a state of dialogue both with each other and with texts from male authors. The female authors use, in their "war talk", literary strategies like "re-reading" and "re-writing" of texts from the "Centre". On the one hand, these strategies enable them to make the blind spots of a male dominated literary discourse apparent/visible on the other hand, they facilitate the negotiation of gender relations and of the war itself, its causes, trigger points and consequences. The female authors represent war as "sexual disorder", as gender war. The study shows that in order to be able to locate an author''s perspective (and to avoid rash conclusions) it is essential to consider the different factors determining it - besides ethnicity and gender, also age, race, the grade of emotional involvement or distance etc. It is in this regard, where the paratexts play an important part, as in these authors express their personal views and comments on the war. The thesis is located at the interfaces of several disciplines: literary, historical and gender studies. The introduction deals with the theoretical backgrounds in the context of war, literary representation and gender. The first chapter is dedicated to the historical context of the Nigerian Civil War including the role of women. The second chapter looks at the paratexts, different representations of the war''s causes, the self-image, the enemy''s image and the future. The third chapter finally deals with the question how the relationship between Civil War and gender war is negotiated/conveyed through the medium of the literary texts. In the conclusion the results are summarized and prospects for future research are discussed. The appendix contains a preliminary bibliography of all literary texts on the Nigerian Civil War written by female authors.