Dissertations / Theses: 'Environmental aspects of Civil engineering'

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Kim, Carl Chong-Soo. "Geotechnical aspects of recirculating well design." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/44495.

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Mneimneh, Saadeddine S. "Algorithmic aspects of high speed switching." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/8373.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.
Includes bibliographical references (p. 145-148).
A major drawback of the traditional output queuing technique is that it requires a switch speedup of N, where N is the size of the switch. This dependence on N makes the switch non-scalable at high speeds. Input queuing has been suggested instead. The introduction of input queuing creates the necessity for developing switching algorithms to decide which packets to keep waiting at the input, and which packets to forward across the switch. In this thesis, we address various algorithmic aspects of switching. We prove in this thesis, that many of the practical switching algorithms still require a speedup to achieve even a weak notion of throughput. We propose two switching algorithms that belong to a family to which we refer in this thesis as priority switching. These two algorithms overcome some of the disadvantages in existing priority switching algorithms, such as the excessive amount of state information that needs to be maintained. We also develop a practical algorithm that belongs to a family to which we refer in this thesis as iterative switching. This algorithm achieves high throughput in practice and offers the advantage of not requiring more than one iteration, unlike other existing iterative switching algorithms which require multiple iterations to achieve high throughput. Finally, we address the issue of using switches in parallel to accommodate for the need of speedup. We study two settings of parallel switches, one with standard packet switching, and one with flow scheduling, in which flows cannot be split across multiple switches.
by Saadeddine Mneimneh.
Ph.D.

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El-Hajaji, A. H. S. "Desalination technologies and environmental aspects : case study in Libya." Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/8585/.

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Water, otherwise known as the pool of life, is the very essence of all living things and as such is vital for survival, whether for living beings, social, economic development or for environmental sustainability. However, its continuing existence is severely threatened for future as a result of climate change, carbon footprint, population growth, environmental damage, combined with natural disasters like droughts and floods. The prospect of an alternative solution such as desalination of sea or brackish water to counter the limit on conventional water resources such as groundwater, which cannot meet demand, is therefore very promising, particularly in arid and semi-arid regions where water scarcity and impaired quality prevails. Consequently, desalination technology has now become a burgeoning industry in North Africa or southern Mediterranean countries, such as in Libya. However, evidence suggests that as a result of by-products being discharged directly into the sea, particularly from coastal desalination plants, the physico-chemical parameters of the receiving water are changing and posing a threat to marine ecosystems. As a result of studies conducted on these parameters to analyse the brine emitted from the Zwuarah and the West Tripoli distillation plants (ZWDP & WTRIS) on the Libyan coastline, evidence shows there is a significant positive correlation at both sites between the biological data and physico-chemical parameters (rs=0.673; p=0.002) and (rs=0.637; p=0.003), which is a clear indication of the impact of brine disposal from both plants on the marine environment. For most of coastal desalination plants on the Libyan coastline, the most practical and least expensive brine disposal option is to discharge it into the sea. It is necessary therefore, to effectively manage desalination reject brine in order to ensure more efficient disposal and reuse. Therefore, it is suggested that experimental studies are aimed for dual benefit of on-site generation of sodium hypochlorite through brine electrolysis and to recover minerals and NaCl from the brine using evaporation ponds, while protecting the environment. Following the first experiment, the outcome of brine utilisation showed a significant production of NaOCl using graphite electrodes (MCCA 1.82 gr/m3). At interelectrode spacing 2 cm and 4 cm, the power consumption was higher, with a greater concentration of sodium hypochlorite generation varying between 10-25 kw/m3 (573-2140ppm) and 29-24 kwm-3 (572-2600ppm) than at interelectrode spacing 6cm 17-13 kwm-3 (350-1790ppm). Consequently, the selection of an optimum electrical consumption level is key in establishing the best scenario in terms of economy and efficiency. Subsequent to the second experiment of brine evaporation in the ponds, results showed that the evaporation rate in August was lower than in September (9.06 mmday-1, 14.63 mmday-1) respectively. The results of the SEM/EDS test showed that due to elevated surges of Na+ and Cl-, halite (NaCl) was the main mineral evident during crystallisation of the salt samples. Hence, the two experiments reveal that brine can be recycled productively, while protecting the environment.

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Alverbro, Karin. "Environmental and ethical aspects of destruction of ammunition." Licentiate thesis, KTH, Miljöstrategisk analys, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27345.

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Many decision-making situations today affect the safety of individuals and the environment,for instance hazardous waste management. In practice, many of these decisions are madewithout an overall view and with the focus on either the environment or safety. Now and then the areas of regulation are in conflict, i.e. the best alternative according to environmental considerations is not always the safest way and vice versa.A tool for taking an overall view within the areas of safety and environment would simplify matters and provide authorities and industry with a better basis for their work. This thesis forms part of a project which aims to develop a framework tool giving this overall view and supporting decision-making in which the issues (areas) of environment, safety, ethics and costs are all integrated. By developing a framework tool, different areas of interest could be taken into consideration more easily when a decision is to be made and could also help develop legislation and policy locally (at an industry or company), nationally and internationally. The project also aims to provide knowledge about different destruction/decommission methods, their good and bad points and their consequences, in order to provide different actors with a better basis for decision-making. This thesis focuses on development of the framework. The scope of the studies was restricted to environment, ethics and personnel safety due to the extent of the work and time limitations. In the next part of the project, the areas of costs and evaluation will be studied and a first draft of the framework tool will be presented. In order to develop the framework tool, two case studies were carried out here: an environmental analysis involving a life cycle assessment and an ethical analysis. With the help of these analyses, three different methods of destruction of ammunition were compared: Open detonation, modelled both with and without recovery and recycling of metals; incineration in a static kiln with air pollution control combined with recycling of metals, modelled with two different levels of air emissions; and a combination of incineration with air pollution control, open burning, recovery of some energetic material and recycling of metals, giving a total of five options. Every method of destruction of energetic material, i.e. explosive waste or ammunition, results in environmental impacts in both the short and long term. These environmental impacts have direct or indirect impacts on safety, quality of life, the economy, etc., now and in the future, locally and globally. Life cycle assessment revealed two factors of importance for reducing the environmental impacts: Recycling the metals and air pollution control. As a consequence of controlling these potential negative environmental impacts, safety problems might also be controlled. Ethical analysis revealed that future generations and people in foreign countries will be affected by the destruction of ammunition. When choosing a method for destruction of ammunition, this group (the general public) should thus be given special attention.
QC 20101210

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Elvin, Alex A. (Alex Allan). "Several aspects of polycrystalline ice behavior based on micromechanical modeling." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/42575.

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Burroughs, Gary Leslie. "The response to environmental economic drivers by civil engineering contractors in South Australia." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09ENV/09envb972.pdf.

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Bibliography: leaves 91-93. Examines the response of two civil engineering construction contractors in South Australia to environmental economic conditions and market requirements using primarily an action research methodology whilst the researcher was engaged as the environmental manager at both corporations.

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Huang, Enyang. "Algorithmic and implementation aspects of on-line calibration of Dynamic Traffic Assignment." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60808.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.
Cataloged from PDF version of thesis. Page 114 blank.
Includes bibliographical references (p. 109-113).
This thesis compares alternative and proposes new candidate algorithms for the online calibration of Dynamic Traffic Assignment (DTA). The thesis presents two formulations to on-line calibration: 1) The classical statespace formulation and 2) The direct optimization formulation. Extended Kalman Filter (EKF) is presented and validated under the state-space formulation. Pattern Search (PS), Conjugate Gradient Method (CG) and Gradient Descent (GD) are presented and validated under the direct optimization formulation. The feasibility of the approach is demonstrated by showing superior accuracy performance over alternative DTA model with limited calibration capabilities. Although numerically promising, the computational complexity of these base-line algorithms remain high and their application to large networks is still questionable. To address the issue of scalability, this thesis proposes novel extensions of the aforementioned GD and EKF algorithms. On the side of algorithmic advancement, the Partitioned Simultaneous Perturbation (PSP) method is proposed to overcome the computational burden associated with the Jacobian approximation within GD and EKF algorithms. PSP-GD and PSP-EKF prove to be capable of producing prediction results that are comparable to that of the GD and EKF, despite achieving speed performance that are orders of magnitude faster. On the side of algorithmic implementation, the computational burden of EKF and GD are distributed onto multiple processors. The feasibility and effectiveness of the Para-GD and Para-EKF algorithms are demonstrated and it is concluded that that distributed computing significantly increases the overall calibration speed.
by Enyang Huang.
S.M.

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Okioga, Teshamulwa (Teshamulwa Irene). "Water quality and business aspects of sachet-vended water in Tamale, Ghana." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39278.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2007.
Includes bibliographical references (leaves 119-126).
Microbial water quality analyses were conducted on 15 samples of factory-produced sachet water and 15 samples of hand-tied sachet water, sold in Tamale, Ghana. The tests included the membrane filtration (MF) test using mColiBlue24® medium, 3MTM PetrifilmTM test, and Hydrogen Sulfide Presence Absence (P/A H2S) test. With the MF method, 1 factory-produced and 1 hand-tied sachet-water sample had E.coli counts of 5 CFU/100ml and 49 CFU/100ml respectively. Almost half (47%) of the factory-produced sachet-water samples had some total coliforms (range from 1 CFU/100ml to 115 CFU/100ml). All the 15 hand-tied sachet-water samples had total coliforms (range from 4 CFU/100ml to 2010 CFU/100ml). One sample recorded TNTC at a dilution factor of 10. The MF method showed little correlation with the 3MTM PetrifilmTM method (R=0. 16). With the 3MTM PetrifilmTM test method, none of the factory-produced sachet-water samples had E.coli and only one sample had total coliforms with 100 CFU/100ml. The hand-tied sachet-water sample with 49 E.coli CFU/100ml in the MF test, turned out to have 100 CFU/100ml in the 3MTM PetrifilmTM test. The MF test results were considered more reliable.
(cont.) For the P/A H2S test, 7% of factory-produced sachet-water samples and 27% of the hand-tied sachet-water samples returned positive results. Overall, hand-tied sachet water was found to be two times more microbially contaminated than factory-produced sachet water. Turbidity tests done on the samples showed that 93% of the hand-tied sachet-water samples and 20% of factory-produced sachet-water samples had turbidities greater than 5 NTU - the limit set by the 1998 Ghana Standards for drinking water. Out of 30 random passer-byes in Tamale and neighboring Savelugu that were interviewed, all drank sachet-vended water, signifying its popularity in the areas. For 37%, sachet water formed the sole supply of drinking water, even at home! 70% drank more water when away from home, 20% the same amount at home and away from home, while 10% drank more water at home. Sachet water formed the main source of water away from home. Sachet-water vendors made 100% to 400% profit.
by Teshamulwa Okioga.
M.Eng.

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MacDonald, Elaine. "Aspects of competitive adsorption and precipitation of heavy metals by a clay soil." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26406.

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This thesis examines the retention of three heavy metals (Pb, Cu, Zn) on a predominantly illite clay soil initially saturated with calcium and magnesium. The heavy metal retention mechanisms were examined both experimentally, using batch equilibrium and precipitation tests, and analytically, using the geochemical equilibrium speciation model MINTEQA2. Heavy metal retention was examined in both non-competitive (single metal) situations and competitive (multi-metal) situations. A definite adsorption selectivity order of Pb $>$ Cu $ gg$ Zn was established, as has been found by many other researchers. Retention by ion exchange adsorption was observed by comparing the total amount of heavy metals retained to the total amount of initially adsorbed calcium and magnesium released. In most cases, it was found that ion exchange was the dominant retention mechanism, even at neutral equilibrium pH values. The effect of initial heavy metal solution pH on heavy metal retention was explored. A comparison was made between batch equilibrium tests performed with metal solutions adjusted to an initial pH of 3 and tests performed with metal solutions that were not adjusted and thus at a higher initial pH. In many cases it was found that greater overall retention occurred when initial metal solutions were at a pH of 3 as opposed to a higher initial pH. The speciation modelling, when compared to the experimental results, was found to adequately predict heavy metal retention in simple single metal batch equilibrium tests but in more complicated multi-metal scenarios the modelling had limited success.

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Malmqvist, Tove. "Methodological aspects of environmental assessment of buildings." Doctoral thesis, KTH, Miljöstrategisk analys, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9742.

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The built environment contributes extensively to the overall environmental impact of society. An increasing number of tools have been developed worldwide for comprehensive environmental assessment and rating of buildings in order to make the building sector more sustainable. These tools are expected to drive and facilitate future environmental improvements and market transformation in the sector. This thesis explores different methodological aspects in tool development using experiences from two large Swedish projects, the EcoEffect and ByggaBo tools, which were developed with a high level of stakeholder participation in order to be of practical use in the building sector. The methodological aspects explored and discussed here include an approach for systematic selection of assessment aspects (energy use, indoor air quality, etc.) in tools (Paper 3), and a systematic procedure for selecting practical indicators using theoretical (e.g. validity/environmental relevance) and practical (e.g. costs) criteria (Papers 2 and 3). An approach for simple communication of complex results is presented with examples from 26 multi-family buildings (Paper 4). This approach allows a building’s ‘environmental efficiency’ to be presented in one diagram, without weighting the two distinct assessment areas energy use and indoor environmental quality. Paper 5 discusses the contextual issue of internal use of environmental indicators in property management organisations through reviews of environmental performance evaluation and organisation theory literature and comparisons with actual case studies. The EcoEffect (Paper 1) and the ByggaBo tools are also compared and summarised. The case studies of real buildings and experiences from the EcoEffect and ByggaBo projects allowed data collection, calculation procedures and different practical applications of such tools to be evaluated. Poor data availability sometimes limits assessments, and improved internal routines and database developments in the building sector would allow more reliable environmental assessments. Reviews of numerous indicators in Paper 3 (and 2) and literature revealed that environmental relevance was not a key aspect when current environmental performance indicators and building rating tools were constructed. This thesis suggests that environmental relevance and systematic procedures be prioritised in order to provide robust and trustworthy tools for environmental assessment of buildings. Recommendations, some of which are generally applicable to other environmental assessments, include selection of environmentally relevant indicators, systematic procedures for handling theoretical and practical considerations in tool development, aggregation and weighting methods, use of a life cycle perspective and inclusion of performance-based rather than feature-based indicators. Since it is likely that the information these tools provide will increasingly be used by authorities, building users, economic incentive providers such as banks, etc., the methodological developments suggested here to strengthen tool rigour are important for future tool development processes.
Utvecklingen av verktyg för miljöbedömning av byggnader är ett område som expanderat kraftigt sedan 1990-talets början. Den ökande medvetenheten om den byggda miljöns omfattande bidrag till samhällets miljöpåverkan i stort har spelat stor roll för denna utveckling. Verktygen förväntas ha en betydelsefull roll i att driva på och underlätta miljöförbättringar och omdaning av marknaden i bygg- och fastighetssektorn. Denna avhandling utforskar olika metodaspekter för verktygsutveckling och bygger på erfarenheterna från två stora svenska metodutvecklingsprojekt för miljöbedömning av byggnader, EcoEffect och ByggaBo:s miljöklassning av byggnader. Båda dessa verktyg togs fram i samarbete med ett stort antal representanter från bygg- och fastighetssektorn, då verktygen syftade till praktisk användning. Ett antal metodaspekter utforskas och diskuteras i avhandlingen. I artikel 3 föreslås och testas ett angreppssätt för systematiskt urval av miljöaspekter som ska bedömas av ett verktyg och dessutom föreslås här och i artikel 2 ett systematiskt tillvägagångssätt för att välja indikatorer för praktiskt användning utifrån både teoretiska (t ex. validitet) och praktiska (t ex. kostnad) kriterier. Ett angreppssätt för att underlätta kommunikation av komplexa miljöbedömningsresultat presenteras genom exempel från 26 flerfamiljshus i artikel 4. Detta angreppssätt möjliggör att redovisa en byggnads ‘miljöeffektivitet’ i ett diagram utan att behöva vikta de två disparata miljöaspekterna energianvändning och innemiljö. Artikel 5 tar upp användning av miljöindikatorer för internt arbete i fastighetsförvaltande organisationer genom litteraturöversikter inom områdena utvärdering av miljöprestanda och organisationsteori samt genom jämförelser med praktiska fallstudier. Verktygen EcoEffect (artikel 1) och nuvarande version av ByggaBo:s miljöklassningssystem sammanfattas också och jämförs i avhandlingen. Genom ett antal fallstudier av verkliga byggnader och erfarenheterna från EcoEffect- och ByggaBo-projekten utvärderas frågor som insamling av indata, beräkningsmetoder och olika praktiska tillämpningar i avhandlingen. Dålig tillgång på indata begränsar ibland möjligheterna att göra miljöbedömningar. Förbättrade interna rutiner samt utveckling av nya typer av databaser inom bygg- och fastighetssektorn kommer med största sannolikhet att underlätta miljöbedömningar i framtiden. Granskning av ett stort antal miljöindikatorer i artikel 3 (och 2) och litteratur på området visade att när miljöindikatorer och miljöklassningsmetoder tagits fram, har miljörelevansen hos dessa sällan haft högsta prioritet. Ett övergripande mål för denna avhandling har därför varit att bidra med rekommendationer som kan stärka miljörelevansen och trovärdigheten hos liknande indikatorer och verktyg. Några av de angreppssätt som föreslås är tillämpliga mer generellt också för andra typer av miljöbedömningar; t ex. hur miljörelevanta miljöindikatorer kan väljas, hur både teoretiska och praktiska överväganden kan hanteras på ett systematiskt sätt vid liknande verktygsutveckling, angreppssätt för viktning och aggregering av resultat samt användning av ett livscykelperspektiv. Vid miljöbedömning av byggnader bör också funktionsbaserade indikatorer i första hand väljas snarare än sådana som baseras på specifika tekniska utföranden. En trolig utveckling är att nya typer av användare i större utsträckning kommer att efterfråga den information som miljöbedömningsverktyg för byggnader kan tillhandahålla. Det kan handla om t ex. myndigheter, husköpare och ekonomiska incitamentsgivare såsom banker. Av denna anledning är de frågor som rör metodutveckling och tas upp i avhandlingen, klart betydelsefulla för att stärka noggrannhet, robusthet och trovärdighet i framtida utveckling av miljöbedömningsverktyg för byggnader.
QC 20100601
Miljöklassning av byggnader
EcoEffect - miljövärdering av byggnader
Miljöstyrning med miljöindikatorer i fastighetsförvaltning

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Wang, Chao. "Present status and future trends of end-of-life vehicles in Macau." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2492993.

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Kong, Kong Hang. "Chemical aspects of coagulation in water treatment." Thesis, University of Macau, 2000. http://umaclib3.umac.mo/record=b1445036.

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Baxter, Travis. "Engineering and legal aspects of a distributed storage flood mitigation system in Iowa." Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/2672.

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This document presents a sketch of the engineering and legal considerations necessary to implement a distributed storage flood mitigation system in Iowa. This document first presents the results of a simulation done to assess the advantages of active storage reservoirs over passive reservoirs for flood mitigation. Next, this paper considers how forecasts improve the operation of a single reservoir in preventing floods. After demonstrating the effectiveness of accurate forecasts on a single active storage reservoir, this thesis moves on to a discussion of distributed storage with the idea that the advantages of active reservoirs with accurate forecasting could be applied to the distributed storage system. The analysis of distributed storage begins with a determination of suitable locations for reservoirs in the Clear Creek Watershed, near Coralville, Iowa, using two separate algorithms. The first algorithm selected the reservoirs based on the highest average reservoir depth, while the second located reservoirs based on maximizing the storage in two specific travel bands within the watershed. This paper also discusses the results of a land cover analysis on the reservoirs, determining that, based on the land cover inundated, several reservoirs would cause too much damage to be practical. The ultimate goal of a distributed storage system is to use the reservoirs to protect an urban area from significant flood damage. For this thesis, the Clear Creek data were extrapolated to the Cedar River basin with the intention to evaluate the feasibility and gain a rough approximation of the requirements for a distributed storage system to protect Cedar Rapids. Discussion then centered on an approximation of the distributed storage system that could have prevented the catastrophic Flood of 2008 in Cedar Rapids. There is significant potential for a distributed storage system to be a cost effective way of protecting Cedar Rapids from future flooding on the scale of the Flood of 2008. However, more analysis is needed to more accurately determine the costs and benefits of a distributed storage system in the Cedar River basin. This paper also recommends that a large scale distributed storage system should be controlled by an entity be created within the Iowa Department of Natural Resources. A smaller distributed storage system could be managed by a soil and water conservation subdistrict. Iowa allows for condemnation of the land needed for the gate structures and the flowage easements necessary to build and operate a distributed storage system. Finally, this paper discusses the environmental law concerns with a distributed storage system, particularly the Clean Water Act requirement for a National Pollutant Discharge Elimination System permit.

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Beck, Julia S. (Julia Samantha). "Downstream changes in river morphology as a result of dam developments." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52243.

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Thesis (MEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: A dam can have a significant impact on the downstream river morphology by altering both the flow regime and the sediment load. The effect of a dam is dependent on factors such as the storage capacity relative to the mean annual runoff (MAR), the operation of the reservoir and the sediment yield of the catchment. Changes in the river morphology include the degradation and coarsening of the riverbed, generally closer to the dam, and aggradation further downstream where the sediment delivered by tributaries cannot be carried through because of the reduced sediment transport capacity of the river. The impact of a dam can stretch over several hundreds of kilometres. The main objective of this thesis was to gain a better understanding of the impacts that dams can have on the downstream river morphology. This was done by developing equations that can describe the channel geometry, investigating the effect of the presence of clay and silt on the sediment transport behaviour of sediments, as well as detailed evaluation of simulations carried out with a one-dimensional mathematical river model (MIKE 11). The calibrated regime equations were found to be comparable to other internationally developed regime equations and to be suitable for natural rivers. It was found, however, that these regime equations are not applicable to rivers downstream of dams that have highly unnatural release patterns. Further research is needed in this regard. By investigating the effect of cohesive sediments on the sediment transport behaviour of mixed sediments it was found that as little as 7% clay and silt in the bed could affect their sediment transport characteristics. A methodology was also developed by which the critical conditions for mass erosion of cohesive sediments can be described in terms of the applied stream power. Sediment transport equations were calibrated and verified in terms of the unit input stream power for fine and non-cohesivesediments. The sediment transport equation for fine sediments was implemented in MIKE 11. The simulations over a 40 km reach of the Pongola River downstream of Pongolapoort Dam, have shown that even when a large demand is placed on the stored water, and most of the smaller floods are therefore absorbed by the dam, the downstream impact can still be considerable, with as much as 5 m deep erosion in places. The sediment loads are generally reduced (by as much as 35%), but the effective catchment area downstream of the dam has been reduced by as much as 90%, indicating that substantial erosion had to have taken place in the river. Coarsening of the riverbed was also observed during the simulations.
AFRIKAANSE OPSOMMING: 'n Dam kan 'n aansienlike impak he op die riviermorfologie stroomaf daarvan, deurdat dit beide die vloei en sedimentlading drasties kan verander. Die effek van 'n dam hang van verskeie faktore af, soos die opgaarkapasiteit in vergelyking met die gemiddelde jaarlikse afloop (GJA), die bestuur van die dam en die sedimentlewering van die opvanggebied. Veranderings in die riviermorfologie behels die degradering van die rivierbed, sowel as die uitspoel van fyn materiaal uit die rivierbed, veral nader aan die dam. Deponering vind verder stroomaf van die dam plaas, waar die sediment wat deur die sytakke ingevoer word nie deurgevoer kan word nie, weens die verlaagde sedimentdravermoe van die rivier. Sodoende kan rivierlope oor honderde kilometers deur 'n dam bemvloed word. Die hoofdoel van die tesis was om meer insig te verkry oor die impak wat damme op die stroomaf riviermorfologie kan he. Derhalwe is vergelykings ontwikkel wat die riviermorfologie kan beskryf. Die effek van die teenwoordigheid van klei en slik op die sedimentvervoer-eienskappe is ondersoek, en gedetaileerde ontledings is met 'n een-dimensionele wiskundige riviermodel (MIKE 11) is gedoen. Daar is bevind dat die regime-formules goed vergelyk met ander intemasionaalontwikkelde formules en dat hulle geskik is vir toepassing op natuurlike riviere. Daar is egter gevind dat die formules nie geskik is vir riviere wat stroomaf Ie van damme wat hoogs onnatuurlike loslatings het nie. Verdere navorsing is op hierdie gebied nodig. Ondersoek na die effek wat klei en slik op die sedimentdravermoe het, het getoon dat slegs 7% klei en slik in die rivierbed die sedimentvervoer-eienskappe van mengsels van fyn en growwe materiaal kan bemvloed. 'n Metode is ontwikkel waarmee die kritiese toestande vir massa-erosie van kohesiewe sediment beskryfkan word in terme van die aangewende stroomdrywing teen die bed. 'n Sedimentvervoer-vergelyking in terme van die eenheids-insetstroomdrywing vir fyn en nie-kohesiewe sedimente is gekalibreer en geverifieer. Die nuwe sedimentvervoer-vergelyking vir fyn sedimente is gebruik in die MIKE 11 simulasies. Hierdie simulasies oor 'n 40 km loop van die Pongolarivier stroomaf van Pongolapoort Dam, het getoon dat selfs as daar 'n groot aanvraag op 'n dam se water geplaas word, en gevolglik meeste van die kleiner vloede deur die dam geabsorbeer word, die impak van die dam nogs steeds aansienlik kan wees, met soveel as 5 m diep uitskuring in plekke. Die sedimentladings het gewoonlik verminder (met soveel as 35%), maar die die effektiewe opvanggebiedarea stroomafvan die dam het met meer as 90% verminder, wat daarop dui dat daar aansienlike erodering in die rivier plaasgevind het. Die simulasies het ook getoon dat die hoeveelheid fyn materiaal in die rivierbed verminder het.

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Barber, Richard Henry 1942. "Arroyo Chico: The effects of design and management on the biological and social aspects of an urban wash." Thesis, The University of Arizona, 1995. http://hdl.handle.net/10150/278512.

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Arroyo Chico Wash, an important drainage for central Tucson, Arizona, runs through numerous neighborhood and industrial areas before emptying into the Santa Cruz River. Within four suburban neighborhoods along the wash, direct observations, personal interviews, survey questions, and historical documents are used to describe design and management influences on the biological and human aspects of the wash. Plants along the wash are identified by 2-meter wide belt transects run at 100-meter intervals over the 4 kilometer length of the study area. Wild animal and bird lists are based on observation and information given by residents. Relationships between design, maintenance and neighborhood attitudes toward the wash are assessed using a survey questionnaire given to people living adjacent to the wash. Results show the wash in the Colonia Solana neighborhood has the greatest biological diversity, highest neighborhood satisfaction and highest recreational use. In neighborhoods where the wash is a "backyard easement", satisfaction and use are the lowest.

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Slavin, Courtney Natasha. "The Relationship Between Traffic Signals and Pedestrian, Bicyclist and Transit User Exposure in Urban Areas." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/616.

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Improving the efficiency of traffic operations along arterials is currently a priority for many agencies as their roadway infrastructure is built out to the largest possible capacity within the urban environment. Many advanced systems are being implemented to optimize traffic signal timing. Air quality is typically not a consideration when these decisions are made. The relationship between exposure to air pollution and traffic signal timing has not been fully explored by other researchers. This study is the first research effort to combine detailed traffic signal timing data (at 5 second intervals) and air pollutant exposure data. Results show that longer green time along the busy arterial reduces pollutant levels, while increased volume per cycle increases pollutant levels. This research quantifies the factors that contribute to pedestrian, bicyclist, and transit user exposure at a busy intersection along an urban arterial. The factors include traffic signal timing, weather related variables, traffic volumes, and heavy vehicle and bus presence. Additionally, the impact of an adaptive traffic signal system on air quality is assessed to understand the implications of signal timing on air pollutant exposure.

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Van, den Heever Johann. "Warm mix asphalt vs. hot mix asphalt : flexural stiffness and fatigue life evaluation." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86439.

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Thesis (MScEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: The UNFCCC (United Nations Framework Convention on Climate Change), enabled by the Kyoto Protocol, set enforced responsibilities on industrialised countries to reduce the amount of emissions (greenhouse gases) produced. This global call for the reduction of greenhouse gas emissions ensured that the manufacturing sector commit to emission reduction. The asphalt industry has embarked on a quest to find alternative methods of producing and constructing asphalt mixes which will release less greenhouse gasses into the atmosphere. These new methods include the reduction in production and construction temperatures which in turn will reduce the amount of greenhouse emissions produced. These new methods introduced the concept of warm mix asphalt (WMA) to the alternative hot mix asphalt (HMA). To produce a WMA mix at lower temperatures the binder needs to be in a workable state so to effectively coat the aggregate and produce a good quality mix. WMA technologies have been developed to enable production of mixes at lower temperatures (effectively reducing emissions) whilst retaining the required binder viscosity and properties needed to produce a quality mix. The question which needs to be answered is whether the performance of these WMA mixes can compare with that of HMA mixes. In this study several WMA mixes (with different WMA technologies) are evaluated against their equivalent HMA mixes in terms of fatigue life and flexural stiffness. Phase angle results were also considered. Flexural stiffness is a mix property which is dependent on loading time and temperature. It is used to measure the load spread ability of a mix and also influences fatigue behaviour. Fatigue cracking occurs in the material as a result of repeated cyclic loading. The evaluation and analysis conducted in this study show that WMA mixes can compare favourably and even exceed that of HMA mixes in certain cases, although some WMA mixes resulted in lower fatigue life or flexural stiffness than its corresponding HMA mixes, which could be attributed to differences in mix components and variables. In this study a literature study, methodology, laboratory test results, a comparison of mix results and conclusions and recommendations are made.
AFRIKAANSE OPSOMMING: Die UNFCCC (United Nations Framework Convention on Climate Change) was in staat gestel deur die Kyoto Protocol om verantwoordelikhede op geïndustrialiseerde lande te forseer om die hoeveelheid van nadelige kweekhuisgasse wat geproduseer word te verminder. Hierdie globale oproep tot die vermindering van kweekhuisgasse verseker dat die vervaardigingsektor hulself verbind tot emissie vermindering. Die asfalt industrie het begin met 'n soektog na alternatiewe metodes van vervaardiging en die bou van asfaltmengsels wat minder kweekhuisgasse sal vrystel in die atmosfeer. Hierdie nuwe metodes sluit die vermindering in produksie en konstruksie temperature in wat op sy beurt die hoeveelheid kweekhuisgasse geproduseer verminder. Hierdie nuwe metodes het die konsep van warm mengsel asfalt (WMA) bekendgestel teenoor die alternatiewe ‘hot’ mengsel asfalt (HMA). Om ‘n WMA mengsel te produseer by laer temperature, moet die bindmiddel in 'n werkbare toestand wees om die aggregaat heeltemal te bedek en 'n goeie gehalte mengsel te produseer. WMA tegnologie is ontwikkel om die produksie van mengsels teen laer temperature te realiseer (vermindering die uitlaatgasse), terwyl die vereiste bindmiddel viskositeit en eienskappe wat nodig is om 'n kwaliteit mengsel te produseer behou word. Die vraag wat beantwoord moet word, is of die prestasie van hierdie WMA mengsel kan vergelyk word met dié van HMA mengsel. In hierdie studie is 'n paar WMA mengsels (met verskillende WMA tegnologie) geëvalueer teen hul ekwivalent HMA mengsels in terme van vermoeiing en buig styfheid. Fase hoek resultate is ook in ag geneem. Buig styfheid is 'n mengsel eienskap wat afhanklik is van die laai tyd en temperatuur. Dit word gebruik om die las verspreiding vermoë van 'n mengsel te meet en beïnvloed ook vermoeiing gedrag. Vermoeidheid krake kom voor in die materiaal as gevolg van herhaalde sikliese laai. Die evaluering en ontleding in hierdie studie toon dat WMA mengsels goed vergelyk en selfs in sekere gevalle meer as dié van HMA mengsels, hoewel sommige WMA mengsels laer vermoeidheid lewe of buig styfheid as die ooreenstemmende HMA mengsels gewys het, wat toegeskryf kan word tot verskille in mengsel komponente en veranderlikes. In hierdie studie word 'n literatuurstudie, metodiek, laboratorium toets resultate, 'n vergelyking van die mengsel resultate en gevolgtrekkings en aanbevelings gemaak.

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Najafi, Mohammad Reza. "Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1114.

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The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS).

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Kime, Robyn Laura. "A two-dimensional numerical model for the investigation of the effects of dams on the Zambezi River Delta." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86402.

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Thesis (MEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: The Zambezi River is the largest east-draining river in Africa. It captures runoff from 8 different countries before draining into the Indian Ocean in Mozambique through the Zambezi Delta which is recognised as a (Ramsar) Wetland of international importance. The Zambezi River flows are currently regulated by four large hydropower dams within its catchment. Much attention has been given in recent literature to the detrimental effects of the altered flow regime as a result of dams on the Zambezi River and the Delta in particular. Existing research relating to these negative effects includes many detailed ecological, hydrological and qualitative morphological studies but to date no detailed morphological modelling studies have been conducted in this regard. In this thesis a two-dimensional coupled hydrodynamic and morphological numerical model of the Zambezi Delta is created using topographical information obtained from a navigational study (Rio Tinto, 2011). The model hydrodynamics are calibrated using recorded water levels and flows at two gauging stations within the model domain. The bed load sediment transport is calibrated using field measurements (ASP, 2012b). The effects of dams on the Zambezi Delta are investigated by performing two 10 year simulations, one representing the current (post-dam) scenario and the other representing a pre-dam scenario. These simulation results show a significant decrease in flooded areas and sediment movement on the floodplains as a result of dams. Additional effects on channel widths and depth, on bed gradings, and on tidal water level variations are analysed. The model is then used to simulate a proposed environmental flood release scenario. Such releases have been recommended as a means to partially mitigate the negative impacts of dams on the Zambezi River. In this case an annual flood release supplying a peak flow of 8500 m3/s (slightly less than the pre-dam mean annual flood of 10 000 m3/s) was found to cause slightly more flooding of the close floodplains and to have small effects on the river channel width. The model predicts hydrodynamics and bed sediment transport of non-cohesive sediments with suitable accuracy but an issue with the suspended transport of cohesive sediments was identified. Recommendations are made for addressing the suspended sediment transport inaccuracy. The model, in its current form, can provide quantitative information regarding the hydrodynamics and course sediment transport of the general delta region on a coarse scale. With additional computational resources and accurate topographical information the model can be refined to give accurate predictions for localised areas within the delta. Such information would be valuable to specialist studies addressing the environmental effects of various proposed flooding scenarios or future dams.
AFRIKAANSE OPSOMMING: Die Zambezirivier is die grootste oos-dreineerende rivier in Afrika. Dit ontvang afloop van ag verskillende lande voor dit in die Indiese Oseaan in Mozambiek uitmond. Die Zambezidelta work erken as 'n RAMSAR vleiland van internasionale belang. Die vloei in die rivier word tans gereguleer deur vier groot hidro-elektriese damme binne sy opvangsgebied. Baie aandag is in die onlangse literatuur gegee aan die nadelige gevolge van die veranderde vloei as gevolg van damme op die Zambezi Rivier en spesifiek op die Delta. Bestaande navorsing met betrekking tot hierdie negatiewe effekte sluit in detail ekologiese, hidrologiese en kwalitatiewe morfologiese studies, maar tot op datum is geen gedetailleerde morfologiese modelleringstudies gedoen nie. In hierdie tesis is 'n twee-dimensionele gekoppelde hidrodinamiese en morfologiese numeriese model van die Zambezi Delta geskep met behulp van topografiese inligting wat verkry is uit 'n navigasiestudie (Rio Tinto, 2011). Die model hidrodinamika is gekalibreer deur teen watervlakke en vloei by twee meetstasies in die model domein. Die bedvrag sedimentvervoer is gekalibreer met behulp van veldmetings (ASP, 2012b). Die ȉnvloed van die damme op die Zambezi Delta is ondersoek deur twee 10-jarige simulasies, een wat die huidige ( na-dam ) scenario en die ander wat 'n voor-dam scenario ondersoek. Hierdie simulasie resultate toon 'n beduidende afname in die oorstroomde gebiede en sedimentbeweging op die vloedvlaktes as gevolg van damme. Bykomende effekte op kanaalbreedtes en -diepte, op die bedgraderings , en op getywatervlak variasies is ontleed. Die model is vervolgens gebruik om 'n voorgestelde omgewingings vloedloslaating te ondersoek. Sodanige loslaatings is aanbeveel om die negatiewe impak van damme op die rivier gedeeltelik te verminder. In hierdie geval gee 'n jaarlikse vloedloslaating met 'n piekvloei van 8500 m3/s (effens minder as die voor-dam gemiddelde jaarlikse vloed van 10 000 m3/s) effens meer oorstromings van die vloedvlaktes en het 'n klein uitwerking op die rivierkanaalbreedte. Die model voorspel die hidrodinamika en bedsedimentvervoer van nie-kohesiewe sedimente met betroubaarheid, maar 'n probleem met die vervoer van kohesiewe sedimente is geïdentifiseer. Aanbevelings word gemaak vir die aanspreek van die kohesiewe sedimentvervoer onakkuraatheid. Die model, in sy huidige vorm, kan kwantitatiewe inligting oor die hidrodinamika en natuurlik sedimentvervoer van die algemene delta streek by benadering verskaf. Met bykomende rekenaar hulpbronne en akkurate topografiese inligting kan die model verfyn word om akkurate voorspellings vir plaaslike gebiede binne die delta te gee. Sulke inligting kan waardevol wees vir spesialis-studies van die omgewingsimpakte van verskillende voorgestelde vloedloslaatings of toekomstige damme.

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Lundberg, Kristina. "Rail operation and maintenance in an environmental management system context." Licentiate thesis, KTH, Land and Water Resources Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-248.

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The Swedish National Rail Administration, Banverket, has the overarching sector responsibility for Swedish railways, including a responsibility for implementing and managing the government decision for an ecologically sustainable development. In support of achieving ecologically sustainable development and fulfilment of the national environmental objectives and environmental legislation, Banverket initiated the implementation of an Environmental Management System (EMS) in 1998. The overall aim of this thesis is to examine the EMS applied at Banverket with regard to the identification and monitoring of environmental aspects at the administrative Railway Regions of Banverket. The analysis is based on a qualitative approach comprising questionnaires, interviews, document analysis and participating observations.

Areas for potential improvements are identified. A more stringent use of the EMS is needed in the organisation. Furthermore, a link between activity, aspect and impact when identifying environmental aspects would improve the procedure. Like in other public organisations, the monitoring of environmental aspects at Banverket is insufficient. Introducing indicators and integrating different Government requirements for environmental monitoring into one system, using EMS as a tool would make the system more effective. In the thsesis a framework is proposed for the identification of environmental aspects pertaining to operation and maintenance at Banverket. This framework has an input–output perspective and provides a clear connection between activity, aspect and impact. Furthermore, by establishing the framework on a system used mainly for environmental performance evaluation, a better connection between the identification and monitoring of aspects is created, possibly improving both processes. The framework for the identifica-tion of environmental aspects, as proposed in the thesis, could also be modified and applied in other organisations.

A major conclusion of the study is that the EMS applied at Banverket, in its present form, is not an effective environmental management tool for achieving ecologically sustainable development within the rail sector. Adapted methods for identification and monitoring of environmental aspects for public organisations such as Banverket would facilitate the application of EMS and increase its effectiveness as an environmental tool.

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Trento, Ticiana Patel Weiss. "Determinação de métricas para reprodução da percepção visual por simulações computacionais." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2771.

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A literatura no campo da Arquitetura cita com frequência a iluminação natural como característica importante a ser observada em projetos. Entretanto, seu estudo geralmente trata das propriedades físicas (trajetória e incidência solar) e de métricas como o fator luz diurna, que não necessariamente aproximam o projeto das preferências subjetivas dos futuros ocupantes do espaço. A iluminação natural influencia não apenas a eficiência energética de um edifício, mas a fisiologia e regulação temporal humana e principalmente a forma como se percebe um espaço. Neste contexto, esta pesquisa procura estabelecer a relação entre a iluminação natural, o acesso às vistas e a percepção humana durante três estações do ano – inverno, primavera e verão – em uma câmara climática localizada em Karlsruhe, Alemanha, com o objetivo de determinar se a percepção de luz dos ocupantes da câmara pode ser traduzida pela irradiância global horizontal, iluminância horizontal e vertical e ofuscamento, que podem ser reproduzidos por simulação computacional e utilizados como parâmetros de projetos arquitetônicos. Para tanto, utiliza-se um ambiente controlado (câmara climática), projetado sobre uma plataforma giratória, o qual permite testar-se o efeito da orientação da fachada sobre variáveis subjetivas de participantes voluntários, sob condições experimentais. Trata-se de estudo longitudinal de campo com abordagem quantitativa e coleta de dados por questionário e medições e técnica de simulação computacional. Identificaram-se por simulação computacional as orientações da câmara com maior diferenciação de acesso à luz natural como etapa preliminar. Validadas e revistas as orientações em teste piloto no estudo de campo realizado no âmbito de uma segunda pesquisa, utilizaram-se os dados coletados nessa pesquisa a partir de respostas a um questionário de situações de luz com monitoramento de condições térmicas e de iluminação, interna e externamente à câmara climática estudada. Os dados subjetivos e objetivos foram então confrontados por meio de métodos estatísticos (coeficiente de Pearson, para dados agrupados, e ρ de Spearman, para dados individuais). Os resultados sugerem correlações significativas entre a iluminância horizontal e a vertical em relação à percepção lumínica dos participantes. As correlações com resultados de simulações computacionais, por sua vez, confirmam a predominância da iluminância vertical, bem como a disponibilidade de iluminação natural e Useful Daylight Illuminance como formas de reprodução da iluminância à altura dos olhos.
Daylight is often mentioned as an important factor to be considered in architectural projects. However, it is mostly taken into consideration as regards its physical features (sun path and availability) whose metrics do not necessarily reflect subjective preferences of the occupants, such as the daylight factor. Daylight affects not only energy efficiency, but also human physiology and time setting and, above all, the way one perceives the environment. In this context, this research aims to establish the relationship between daylight, access to views and human perception throughout three seasons – winter, spring and summer – in a climate chamber in Karlsruhe, Germany. Its goal is to determine which metrics better translate visual perception of the chamber occupants and which could also be reproduced in computer simulations and later used as design parameters. For this purpose, a climate chamber, built on top of a rotating platform, was used to test the effect of façade orientation on several subjective variables of volunteers under experimental conditions. This is a longitudinal field study with a quantitative approach that uses instruments such as surveys and measurements, as well as computer simulations as technique. Preliminary computer simulations helped to identify façade orientations with the most differentiation regarding daylight access. After test orientations were validated against field data from a pilot study carried out during a concurrent field study, data collected during such study including survey results as regards light perception and measurements of thermal and lighting conditions, indoors and outdoors were used for analysis. Subjective and objective data were then compared using Pearson´s R coefficient (for grouped data) and Spearman´s rank correlation coefficient (for individual data). Correlation results point to the use of vertical and horizontal illuminance as metrics with the strongest relationship to participants’ light perception. Correlations between measured data and computer simulations confirm the predominance of vertical illuminance, as well as Daylight Availability and the Useful Daylight Illuminance as valid tools to reproduce the illuminance at the eye level.

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Cuifeng, Wei. "Improved Finite Analytic Methods for Solving Advection-dominated Transport Equation in Highly Variable Velocity Field." PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/4922.

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Solute transport studies frequently rely on numerical solutions of the classical advection-diffusion equation. Unfortunately, solutions obtained with traditional finite difference and finite element techniques typically exhibit excessive numerical diffusion or spurious oscillation when advection dominates, especially when velocity field is highly variable. One recently developed technique, the finite analytic method, offers an attractive alternative. Finite analytic methods utilize local analytic solutions in discrete elements to obtain the algebraic representations of the governing partial differential equations, thus eliminating the truncation error in the finite difference and the use of approximating functions in the finite element method. The finite analytic solutions have been shown to be stable and numerically robust for advection-dominated transport in heterogeneous velocity fields. However, the existing finite analytic methods for solute transport in multiple dimensions have the following disadvantages. First, the method is computationally inefficient when applied to heterogeneous media due to the complexity of the formulation. Second, the evaluation of finite analytic coefficients is when the Peclet number is large. Third, the method introduces significant numerical diffusion due to inadequate temporal approximation when applied to transient problems. This thesis develops improved finite analytic methods for two-dimensional steady as well as unsteady solute transports in steady velocity fields. For steady transport, the new method exploits the advantages of the existing finite analytic and finite difference methods. The analytically difficult diffusion terms are approximated by finite difference and numerically difficult advection and reaction terms are treated analytically in a local element in deriving the numerical schemes. The new finite analytic method is extended to unsteady transport through application of Laplace transformation. Laplace transformation converts the transient equation to a steady-state expression that can be solved with the steady version of the improved finite analytic method. Numerical inversion of the transformed variables is used to recover solute concentration in the physical space-time domain. The effectiveness and accuracy of the new finite analytic method is demonstrated through stringent test examples of two dimensional steady-state transport in highly variable velocity fields. The results clearly demonstrated that the improved finite analytic methods are efficient, robust and accurate.

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Siqueira, Adriano Rodrigues. "Processo de interação escola-empresa: o caso do escritório verde da Universidade Tecnológica Federal do Paraná/UTFPR." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/955.

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Esta dissertação apresenta a abordagem da importância da interação universidade empresa no ambiente acadêmico, com foco na descrição da construção da edificação do Escritório Verde da Universidade Tecnológica Federal do Paraná, campus de Curitiba, que foi viabilizado a partir de parcerias com empresas. Analisa as bases históricas das relações universidade-empresa no Brasil, e evidencia as vantagens e necessidades advindas de tal interação do meio acadêmico com o setor produtivo. Discute as motivações que despertaram nas empresas o interesse em investir nesta relação, ofertando produtos e serviços para a viabilização do projeto de construção do Escritório Verde. Demonstra a importância de tal projeto para a universidade, bem como analisa as bases de criação de uma empresa Junior multidisciplinar que terá como sede o Escritório Verde, a qual prestará consultoria verde. Complementando a análise descritiva de como se deu o processo de interação, o estudo verificou por meio de um questionário enviado às principais empresas parceiras quais as expectativas destas quanto a sua participação em um projeto acadêmico e o que elas esperam desta relação após a conclusão da edificação. Traz como resultado as análises destas parcerias, as quais demonstraram que desde que se tenha um ambiente propício com ganhos mútuos, as empresas mostram-se solidárias e agregam-se a projetos acadêmicos. Evidencia o desejo das mesmas em capacitar profissionais em suas tecnologias e serviços ainda na universidade, enxergando a mesma como formadora de mão de obra. Em termos de responsabilidade socioambiental, verificou-se que as empresas desejam vincular seu nome a projetos que remontam a tais iniciativas, tendo em vista que estes trabalham com produtos e serviços que possuem apelo ambiental. O Escritório Verde mostrou-se uma vitrine no ramo da sustentabilidade e conscientização para com o meio ambiente, sendo alvo de inúmeras reportagens em mídias diversas.
This dissertation presents the approach of the importance of university-industry interactions in the academic environment, focusing on the description of the construction of building the Green Office Federal Technological University of Parana, Curitiba campus, which was made possible through partnerships with companies. Analyzes the historical basis of university-business relations in Brazil, and highlights the advantages and requirements arising from this interaction of academia with the productive sector. Discusses the reasons that sparked the interest in the companies to invest in this relationship, offering products and services for the feasibility of the construction of the Green Office. Demonstrates the importance of such a project for the university, as well as examines the foundations of creating a multidisciplinary junior company will be based at the Green Office, which will advise green. To complement the descriptive analysis of how was the process of interaction, the study found through a questionnaire sent to key business partners such as the expectations for their participation in an academic project and they expect this relationship after completion of the building. Bring the analyzes as a result of these partnerships, which demonstrate that since it has an environment conducive to mutual gains, companies appear to be supportive and add to academic projects. It highlights the desire of those in training professionals in their technologies and services still in college, seeing it as a trainer of labor. In terms of social and environmental responsibility, it was found that companies want to link your name to projects that go back to such initiatives, given that they work with products and services that have environmental appeal. The Green Office proved to be a showcase in the field of sustainability and awareness for the environment, the target of numerous articles in various media.

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Khajehei, Sepideh. "From Probabilistic Socio-Economic Vulnerability to an Integrated Framework for Flash Flood Prediction." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4666.

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Flash flood is among the most hazardous natural disasters, and it can cause severe damages to the environment and human life. Flash floods are mainly caused by intense rainfall and due to their rapid onset (within six hours of rainfall), very limited opportunity can be left for effective response. Understanding the socio-economic characteristics involving natural hazards potential, vulnerability, and resilience is necessary to address the damages to economy and casualties from extreme natural hazards. The vulnerability to flash floods is dependent on both biophysical and socio-economic factors. This study provides a comprehensive assessment of socio-economic vulnerability to flash flood alongside a novel framework for flash flood early warning system. A socio-economic vulnerability index was developed for each state and county in the Contiguous United States (CONUS). For this purpose, extensive ensembles of social and economic variables from US Census and the Bureau of Economic Analysis were assessed. The coincidence of socio-economic vulnerability and flash flood events were investigated to diagnose the critical and non-critical regions. In addition, a data-analytic approach is developed to assess the interaction between flash flood characteristics and the hydroclimatic variables, which is then applied as the foundation of the flash flood warning system. A novel framework based on the D-vine copula quantile regression algorithm is developed to detect the most significant hydroclimatic variables that describe the flash flood magnitude and duration as response variables and estimate the conditional quantiles of the flash flood characteristics. This study can help mitigate flash flood risks and improve recovery planning, and it can be useful for reducing flash flood impacts on vulnerable regions and population.

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Hajimirzaie, Seyed Mohammad. "Flow structure in the wake of a low-aspect-ratio wall-mounted bluff body." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/2509.

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The effects of shape and relative submergence (the ratio of flow depth to obstacle height, d/H) were investigated on the wakes around four different low-aspect-ratio wall-mounted obstacles: semi-ellipsoids with the major axes of the base ellipses aligned in the streamwise and transverse directions, two cylinders with aspect ratios matching the ellipsoids. Wake structure of a fully submerged, spherical obstacle was also investigated in the same flow conditions to provide insight into the flow obstacle interaction with ramification to sediment transport. A low-aspect-ratio semi-ellipsoid was chosen as broad representative of a freshwater mussel projecting from a river bed, and a sphere was employed as representative of a boulder. Two cylinders were used due to their similarity to geometries investigated in other studies. Digital Particle Image Velocimetry and thermal anemometry were used to interrogate the flow. For ellipsoids and cylinders, streamwise features observed in the mean wake included counter-rotating distributions of vorticity inducing downwash (tip structures), upwash (base structures), and horseshoe vortices. In particular, the relatively subtle change in geometry produced by the rotation of the ellipsoid from the streamwise to the transverse orientation resulted in a striking modification of the mean streamwise vorticity distribution in the wake. Tip structures were dominant in the former case while base structures were dominant in the latter. A vortex skeleton model of the wake is proposed in which arch vortex structures, shed from the obstacle, are deformed by the competing mechanisms of Biot-Savart self-induction and the external shear flow. An inverse relationship was observed between the relative submergence and the strength of the base structures for the ellipsoids, with a dominant base structure observed for d/H = 1 in both cases. The wake of the sphere is more complex than ellipsoidal geometries. Streamwise features observed in the mean wake including tip, horseshoe structures, and weak upwash. The shedding characteristics and dynamics of the wake were examined. Weak symmetric shedding was observed in the wakes of streamwise and transverse ellipsoids at d/H = 3.9 while cross-spectral measurements confirmed downstream and upstream tilting of arch structures shed by the transverse and streamwise ellipsoids, respectively. Much weaker peaks in the power spectrum were observed for low- and high-aspect-ratio cylinders. While the dominant Strouhal number remained constant as the relative submergence was reduced to d/H = 2.5 for the ellipsoids, it increased abruptly at d/H = 1 and transitioned to an antisymmetric mode. For sphere geometry at d/H = 3.9, a weak dominant frequency was observed close to obstacle junction and the cross-correlation function for symmetric measurements in the wake indicates symmetric shedding. These results demonstrate a means by which to achieve significant modifications to flow structure and transport mechanisms in the flow.

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Travagin, Vinícius Bernardino. "Subsídios para escolha do método construtivo de túneis." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/347.

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Capes
Diante da crescente ocupação dos ambientes urbanos e das demandas por infraestrutura, a ocupação do espaço subterrâneo mostra-se uma opção. Para este fim, os túneis são a principal alternativa, seja para a implantação de redes de utilidades, para transporte rodoviário, para transporte metroviário ou para sistemas de saneamento. Contudo, não se observam estudos de alternativas para a escolha do método construtivo ideal, aquele que seja mais adequado a cada contexto que se apresenta. Assim, a escolha do método construtivo de um túnel, dada a diversidade e complexidade de fatores envolvidos, tem se amparado na experiência adquirida pelos envolvidos com a obra ou em aspectos subjetivos e escusos, podendo ocasionar ora túneis mais onerosos do que deveriam ser, ora túneis de integridade estrutural e funcional comprometida. Neste contexto, o presente estudo apresenta um panorama geral a respeito dos túneis, aspectos qualitativos de estruturas e geotecnia a eles relacionados, os métodos construtivos mais consagrados, as variáveis que possuem interferência direta nos diversos métodos construtivos, os custos técnicos, sociais e ambientais de túneis e o estado da arte no processo decisório para este tipo de empreendimento. Traz como resultado uma sistemática simplificada para escolha do método construtivo, baseada em critérios objetivos e norteada pelo contexto em que a obra se encontra e por seu custo total. O trabalho busca contribuir, assim, com a racionalização da concepção, do projeto e da construção de túneis.
Given the increasing occupation of urban environments and the demands for infrastructure, the use of underground space seems to be an option. For this purpose, tunnels are the main alternative, either for utilities, for road transport, for subway, or for sanitation. However, no studies are observed about comparison of alternatives aiming the choose of the right tunneling method, one that is most appropriate in each context it presents. Thus, the choice of tunneling method, given the diversity and complexity of factors involved, has been done with majority support of the experience gained by those involved with the work or subjective and vain aspects, causing either tunnels more expensive than they should be or tunnels which structural and functional integrity are impaired. In this context, this study presents an overview about the tunnels, geotechnical and structural qualitative aspects related to them, the most established construction methods, variables that have direct interference in the various construction methods, technical costs, social costs and environmental costs involved with tunnels and the state of the art about decision making for this type of venture. As a result, this research gives a systematic and simplified way of choosing the tunneling method, based on objective criteria and guided by the context in which the work is and the total cost. The work seeks to contribute as well, with the rationalization of design and construction of tunnels.

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Van, Glubt Sarah. "Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3486.

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The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids.

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Poiencot, Brandon Keith. "Preliminary Feasibility of Transporting and Geologically Sequestering Carbon Emissions in the Florida Pan-Handle." UNF Digital Commons, 2012. http://digitalcommons.unf.edu/etd/593.

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According to the United States Department of Energy, fossil-fueled power plants account for 78% of stationary source CO2 emission in the United States and Canada. This has led electric utilities across the globe to research different alternatives for energy. Carbon sequestration has been identified as a bridge between fossil fuels and clean energy. This thesis will present research results regarding the transportation costs of CO2 and the suitability of geology in the Florida Pan-Handle for sequestration infrastructure. The thesis will utilize various evaluation tools including GIS, numerical models, and optimization models. Analysis performed for this thesis and review of published literature produced estimated carbon storage capacities for two areas in and near the Florida Pan-Handle. These areas were labeled Disposal Area 1 and Disposal Area 3. Disposal Area 1 was estimated to contain capacity for the storage of 5.58 gigatonnes of CO2. Disposal Area 3 was estimated to contain capacity for the storage of 2.02 gigatonnes of CO2. Transportation scenarios were analyzed over a 25 year period and the capacities above are sufficient to store the CO2 emissions from the Pan-Handle network of power plants for the study period. Four transportation routing scenarios were investigated using transportation costs from the Poiencot and Brown CO2 pipeline capital cost model. The scenarios (models) consisted of the Right-Of-Way, Solo-Funded, Piece-Wise, and Authority models. Each presents a different method for the overall funding of the Florida Pan-Handle CO2 network and produced different total levelized and mean unit costs. The cheapest network on a mean unit cost basis was the network for Disposal Area 1 in the Authority Model, producing a mean unit cost of $0.64 per tonne of CO2.

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Ziegler, Jessica. "How Can the Construction Client Improve the Work Environment in the Real Estate and Construction Process? : An Investigation of the Health and Safety Aspects in the Early Phases." Thesis, KTH, Fastigheter och byggande, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297877.

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During the last decade, the Swedish work environment authority (AV) observed a stagnancy of fatal accidents in Sweden. According to statistics, the building industry in Sweden is one of the third largest industries regarding occupational injuries and the industry with the most severe recorded fatal accidents. Scientific contributions have found that efforts and focus on health and safety aspects during the planning and design phases (early phases) could reduce work environment problems in the construction and maintenance phases. The purpose of this study is to explore how the construction client can improve the health and safety aspects in the early phases to enhance the work environment in the construction and maintenance phases. Further, identify the main challenges of health and safety in the early phases to improve the work environment at the construction and maintenance phases. The study has applied qualitative methods, with 13 semi-structured interviews with senior project managers at a public construction client in Sweden. After analyzing the semi-structured interviews, the findings were discussed with an expert panel for further clarifications. This study has identified that health and safety aspects during the planning and design can improve by different measures and methods to ensure a safer work environment in the construction project. It should be a priority for the construction client to be proactive with the health and safety aspects in the early phases. Furthermore, identified the study three main challenges of health and safety aspects. These challenges of health and safety aspects have been identified as crucial to address in the early phases for succeeding in preventing occupational accidents in construction projects. The first identified challenge is the lack of the construction clients' consciousness of their profound responsibilities in the work environment. The second challenge raised is the insufficient work environment competencies of the applied BAS-P and designers in the construction project. The last identified challenge is the lack of safety communication in the construction project, as the transfer meeting between the BAS-P and BAS-U and lessons learned meetings. The portrayed main challenges seem to face both countries inside and outside the EU, as reasoned from the discussion with Åsgård et al. Furthermore, the work environment is essential for commitment, re-evaluation, and improvements in routine activity. Including the construction clients and the involved actors in the construction process to achieve a construction industry with zero accidents and fatalities.
Arbetsmiljöverket (AV) har under det senaste decenniet observerat en stagnation av dödsolyckor i Sverige. Enligt statistik är byggbranschen i Sverige en av de tredje största branscherna när det gäller arbetsskador och den bransch som har flest registrerade dödsolyckor. Vetenskapliga studier har visat att prioriteringar och fokus på hälsa och säkerhet under planerings- och projekterings skeden (tidiga skeden) kan bidra till att undvika arbetsmiljöproblem på byggarbetsplatsen i produktions skede, liksom i underhållsskedet. Syftet med denna studie är att undersöka hur byggherren kan förbättra hälso- och säkerhetsaspekterna i de tidiga skedena för att förstärka arbetsmiljön i produktions- och underhållsskedena. Även att identifiera de viktigaste utmaningarna för hälso- och säkerhetsaspekter i de tidiga faserna för att förbättra arbetsmiljön i produktions- och underhållsskedena. Studien har tillämpat kvalitativa metoder, där semi-strukturerade intervjuer genomfördes med 13 projektledare hos en offentlig byggherre i Sverige. Efter att ha analyserat resultaten från de semi-strukturerade intervjuerna diskuterades analysen med en expertpanel. Resultatet i denna studie har identifierat att hälso- och säkerhetsaspekter under planering och projektering skedena kan förbättras med olika åtgärder och metoder för att säkerställa en säkrare arbetsmiljö i byggprojektet. Vad man finner är att det bör vara en prioritet för byggkunden att vara proaktiv med hälso- och säkerhetsaspekterna i de tidiga faserna. Tre huvudutmaningar för hälso- och säkerhetsaspekter har dessutom identifierats i resultatet. Dessa utmaningar för hälso- och säkerhetsaspekter ses som avgörande att hantera i de tidiga faserna för att lyckas med förebyggandet av arbetsolyckor i byggprojekt. Den första identifierade utmaningen är bristen på byggherrarnas medvetenhet om deras ansvar i arbetsmiljön. Den andra utmaningen som tas upp är den otillräckliga arbetsmiljökompetensen hos den tillämpade BAS-P och projektörerna i byggprojektet. Den sista identifierade utmaningen är bristen på säkerhetskommunikation i byggprojektet, som överföringsmöte mellan BAS-P och BAS-U och erfarenhetsåterföringsmöten. De viktigaste utmaningarna som presenteras i denna studie för förbättra hälso- och säkerhetsaspekterna i dem tidiga skedena verkar vara utmaningar som finns både i länderna inom och utanför EU, vilket togs upp i diskussionen med Åsgård et al. Dessutom dras slutsatsen att arbetsmiljön är ett viktigt ämne där engagemang, omvärdering och förbättringar bör vara en återkommande aktivitet. För både byggherren och de involverade aktörerna i hela byggprocessen för att uppnå en byggbransch med noll olyckor och dödsfall.

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Laws, Nathan. "A Parabolic Equation Analysis of the Underwater Noise Radiated by Impact Pile Driving." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1083.

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Impact pile driving can produce extremely high underwater sound levels, which are of increasing environmental concern due to their deleterious effects on marine wildlife. Prediction of underwater sound levels is important to the assessment and mitigation of the environmental impacts caused by pile driving. Current prediction methods are limited and do not account for the dynamic pile driving source, inhomogeneities in bathymetry and sediment, or physics-based sound wave propagation. In this thesis, a computational model is presented that analyzes and predicts the underwater noise radiated by pile driving and is suitable for shallow, inhomogeneous environments and long propagation ranges. The computational model uses dynamic source models from recent developments in the technical literature. Pile source models are coupled to a broadband application of the range-dependent acoustic model (RAMPE), a standard parabolic equation (PE) propagation code capable of modeling wave propagation through complex, range dependent environments. Simulation results are shown to be in good agreement with several observations of pile driving operations in the Columbia River between Portland, Oregon and Vancouver, Washington. The model is further applied to extend sound level predictions over the entire river and study the effects of sediment and bathymetry on the underwater sound levels present in the environment.

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Mannisi, Alban. "La médiation environnementale en aménagement du territoire dans la société civile au Japon : pour une philosophie politique du paysage." Thesis, Paris 10, 2017. http://www.theses.fr/2017PA100027.

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Depuis les années 70, des conventions internationales renforcent l’implication des sociétés civiles dans l’aménagement de leur territoire. Au Japon, ce phénomène s’est accéléré suite au tremblement de terre de Kōbe en 1995. Il a débouché en 1998 sur la loi NPO (association à but non lucratif) qui a consolidé le rôle de la société civile dans le jeu des acteurs du territoire. Cette thèse analyse les mécanismes d’engagement de la société civile et le recours à des médiateurs qui s’appuient sur les relations spécifiques de la société nippone à son environnement (milieu japonais), et enquête sur l’apparition de nouvelles formes de gouvernances des territoires. Afin de répondre à cette problématique, il est étudié dans un premier temps l‘émergence du rôle de la société civile, grâce à la médiation dans l’aménagement du territoire au Japon, en montrant comment ces phénomènes s’ancrent pour partie sur certaines logiques traditionnelles, mais également sur des évolutions internationales. Puis, dans un deuxième temps, à partir de l’étude de trois pratiques de médiateurs d’ingénierie sociale : KUWAKO Toshio (philosophe), YAMAZAKI Ryō (paysagiste) et KOIZUMI Hideki (urbaniste), il est observé comment les techniques de médiations inspirées pour partie de techniques étrangères sont assimilées et réajustées pour répondre aux besoins de la société nippone. Cette thèse précise ainsi la porosité entre l’autochtonie et les transferts de méthodes de gouvernance internationale ; elle met en évidence comment les volontés internationales d’implication des sociétés civiles s’inscrivent dans les logiques du milieu japonais. En conclusion, une tentative de mise en perspective des données de la thèse est recherchée à partir de l’énoncé d’une philosophie politique du paysage
Since the 1970s, international conventions have reinforced the involvement of civil societies in the development of their territories. In Japan, this phenomenon was accelerated further to the Kōbe earthquake in 1995. In 1998, it led to the NPO (Non Profitable Organization), which consolidated the role of civil society in the stakeholders' territory. This thesis analyzes the mechanisms of civil society engagement and the use of mediators who rely on the specific relation between Japanese society and its environment (Japanese milieu), and investigates the emergence of new forms of territorial governance. In order to answer this problematic, we first study the emergence of the role of civil society through mediation in territorial planning in Japan, showing how these phenomena are partly based on certain logics, but also on international developments. Then, from the study of three practices of mediators of social engineering: KUWAKO Toshio (Philosopher), YAMAZAKI Ryō (Landscape Architect) and KOIZUMI Hideki (Urban Planner), it is observed how the techniques of mediations inspired part of foreign techniques are assimilated and readjusted to meet the needs of Japanese society. This thesis explains the porosity between autochthony and the transfer of methods of international governance. It highlights how the international will to involve civil societies is part of the logic of the Japanese milieu. In conclusion, an attempt to put into perspective the data of the thesis is sought from the statement of a political philosophy of landscape

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32

Campos, Henrique Marin van der Broocke. "Geração distribuída de energia solar fotovoltaica na matriz elétrica de Curitiba e região: um estudo de caso." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/2004.

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Este trabalho objetiva contribuir com o planejamento da geração de energia elétrica por meio da utilização de geração fotovoltaica de forma distribuída, ou seja, instalada e em operação em paralelo junto com a rede de distribuição de energia elétrica. Utiliza-se uma abordagem hipotético-dedutiva, buscando hipóteses, na forma de questões orientadoras, que serão testadas por meio do tratamento dos dados coletados e sua posterior análise e interpretação. O método de procedimento é o estudo de caso, sendo escolhida a cidade de Curitiba e o restante dos municípios compreendendo sua Região Metropolitana. A partir da elaboração da revisão na literatura, visando constituir a fundamentação teórica desta pesquisa, é elaborado um breve inventário estatístico e do aspecto de geração de energia elétrica da cidade de Curitiba, no contexto do estado do Paraná. Os procedimentos metodológicos envolvem a simulação de cenários de inserção de geração fotovoltaica distribuída, considerando diferentes níveis de penetração, e seus efeitos sobre curvas de carga reais para a cidade de Curitiba. Foram selecionados 12 dias, considerados críticos, para a análise que contemplou a contribuição fotovoltaica em termos da redução do consumo de energia elétrica, redução de emissões de CO2 e, por fim, capacidade do sistema fotovoltaico em reduzir a demanda máxima do sistema elétrico. Constatou-se que o intervalo de capacidade instalada em energia solar fotovoltaica situa-se entre 40,80 MWp e 55,68 MWp, desconsiderando exceções, e remete a valores de máximo Fator Efetivo de Capacidade de Carga (FECC), para condição de irradiação máxima e irradiação típica, no inverno e verão. Dessa forma, este intervalo é considerado apropriado do ponto de vista do aumento da capacidade do sistema elétrico, devido à presença de geradores fotovoltaicos distribuídos. Além disso, o referido intervalo além de aumentar em mais de 50% a capacidade do sistema elétrico, acarreta em redução anual do consumo de energia elétrica entre 50,8 GWh e 69,4 GWh, além de evitar a emissão de 18.501 toneladas de CO2-eq a 25.251 toneladas de CO2-eq, sendo, portanto, um importante vetor para o aumento da oferta de energia elétrica, aumento da capacidade do sistema elétrico e, por fim, redução de emissões de Gases do Efeito Estufa, principalmente o CO2.
This study aims to deepen knowledge in the item electricity generation planning through the use of distributed generation using solar photovoltaic energy, which means that photovoltaic systems are able to operate in parallel with the electricity distribution network. A hypothetical-deductive approach was developed, seeking hypotheses in the form of guiding questions, which will be tested by treatment of the collected data and their analysis and interpretation. The method of procedure is the case study, being applied to the Metropolitan Region of Curitiba. The literature review aims to be the theoretical basis of this research, therefore it mainly consists of a brief statistical and electrical energy inventory of the city of Curitiba in Paraná state. The methodological procedures involve the simulation of different scenarios for distributed PV generators by varying their Penetration Level, so that the effects on actual load curves for the region analyzed were quantified. 12 critical days were selected to the analysis that included the photovoltaic contribution in terms of reducing electrical energy consumption, reducing CO2 emissions and, finally, the capacity of the photovoltaic systems to reduce the maximum demand of the electrical system of the city. It was concluded that the most appropriate PV Penetration Level, in terms of power, regards with 40,80 MWp up to 55,68 MWp, disconsidering exceptions. This result leads to maximum values of Effective Load Carrying Capacity (ELCC), for maximum and typical solar radiation, during the seasons of winter and summer. In result, this proposed interval represents the better peak shaving capability of PV, because of its higher ELCC parameter. Furthermore, in addition to increase more than 50% in the capacity of the electrical system, there is an annual amount of energy generated about 50.8 GWh and 69.4 GWh, which represents 18,501 to 25,251 tons of CO2-eq avoided. For this reason, solar PV energy is an extremely important and feasible strategy to enhance the electricity generation, the capacity of the electrical system and to reduce greenhouse gases emission, especially CO2.

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De, Waal Louise Christina. "Environmental aspects of river management." Thesis, University of Wolverhampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247784.

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This work consists of two distinct and separate sections with differing aims and outcomes. Section A is the critical review, which provides a context for the published work presented in Section B. Section A, the critical review, summarises the current literature in the subject area of environmental aspects of river management and sets the research portfolio in context. The physical landscape has been increasingly influenced by a variety of economic and social changes in recent history. During these approximately 6,000 years, human impact on river systems has been substantial and widespread. The environmental changes, that have stressed river systems, have also damaged their value for both human use and environmental functions. Some of these stresses include changes in water quality and quantity, morphological modifications of the channel and/or floodplain, decline of native species and the introduction of alien species. This has led to changes in current river management philosophy, issues and techniques. Section n, the research portfolio of published work submitted as part of this thesis, focuses on the management of some aspects of environmental change within river systems, particularly problems relating to river rehabilitation and the introduction of invasive riparian plant species. Each published paper has its own individual abstract, summarising the key finding of the research. The research portfolio can be divided into three broad sections. The first section, the main published work, includes those papers approved by the University Research Committee as part of the Registration for the degree of PhD by Published Work in May 2000. These papers form the key part of the thesis. They are introduced in the critical review in the blue text boxes, in order of significance to the text discussed and not in chronological order. They are presented in full in the appendices (numbers as shown below) printed on light blue paper. The next section relates to additional relevant published work. These papers are also submitted as part of this thesis, but are considered to be secondary as a result of their date of publication, i.e. prior to 1995. In order to distinguish these papers clearly from the key papers, they are introduced in the critical review in green text boxes and presented in full in the appendices (numbers as shown below), printed on light green paper. The candidate's approximate contribution and the nature of this contribution to each joint paper have been indicated as a percentage and are shown on the title page of each appendix. The third part is other supporting material and is referred to in the critical review through inclusion of orange-brown text boxes. Since these publications consist mainly of consultancy reports and edited books, they are NOT submitted as part of this thesis and are not presented in full in the appendices. If necessary, this material can be made available to the internal and/or external examiners before or during the viva.

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Campos, Giovana de Almeida Coelho. "Análise da influência do sombreamento causado pelos edifícios na zona central de Curitiba." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1095.

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O crescimento urbano e o ritmo acelerado na concentração de pessoas nas cidades são inevitáveis. A verticalização das construções como solução para atender a necessidade da máxima ocupação do solo e para justificar a infraestrutura investida pelo poder público nas áreas centrais, causa consideráveis impactos no entorno em que estão inseridas. Contudo, a urbanização em si não é um problema, e sim a forma como as cidades estão sendo construídas e ocupadas. Diante disso, o trabalho apresenta como objetivo principal a verificação da influência do sombreamento gerado pelos edifícios altos dentro de um recorte definido na zona com maior capacidade de verticalização em Curitiba. Esta pesquisa foi desenvolvida em quatro etapas: a primeira, de fundamentação teórica com o estudo da literatura existente sobre o tema, a segunda para definição da região de estudo na cidade e os períodos a serem analisados, a terceira etapa para delimitação do recorte de estudo com análises de cada período e, a quarta com a elaboração das simulações computacionais nos softwares Auto CAD, Sketchup Pro, Excel e Ecotect para obtenção de resultados. Durante a evolução da pesquisa, verificou-se que, de fato, o nsombreamento causado pelos edifícios altos comprometem consideravelmente as construções vizinhas a eles e todo o seu entorno imediato. Além disso, foi concluído que Curitiba, uma cidade considerada fria, sofre nos períodos de inverno com o excessivo sombreamento nas áreas públicas entre quadras. Em contrapartida, as áreas abertas de lazer estão posicionadas adequadamente e não se prejudicam com a verticalização da Zona Central. De qualquer forma, a intenção de redução de impacto gerado por esses processos deve ser planejada em um contexto mais significativo. A elaboração de projetos deve ter como premissa a adequação ao clima e ao contexto local, da mesma forma que devem ser analisados os impactos ambientais dessas sobre as construções vizinhas e os espaços externos localizados em uma área de influência. A idéia de preservar o skyline já consolidado na cidade, evitando edifícios muito altos, pode ser uma alternativa para minimização dos impactos de sombreamento.
Urban growth and the fast pace in the concentration of people in cities are inevitable. Building verticalization as a solution to attend the need of maximum land use and to justify the infrastructure invested by the government in central areas, cause considerable impacts on the environment which they are. However, urbanization is not a problem itself, but how cities are being built and occupied. Thus, the main goal of this work is to verify the shadow influence caused by tall buildings in a specific area inside of the zone with more capacity of verticalization in Curitiba. This research was developed in four steps: the first one was to study the existing literature about this topic, second to define study section in the city and periods to be analyzed, third step to delimit a zoom of study with analysis about all periods and, fourth with computer simulations on Auto CAD, Sketchup Pro, Excel and Ecotect softwares to obtain important results. During the evolution of this work, it was verified that the shading caused by tall buildings undertake considerably neighboring buildings and all surrounding area. Furthermore, it was concluded that Curitiba, a cold city, suffers in winter season due to excessive shading in public spaces between blocks. On the other hand, open spaces as squares are correctly positioned and do not harm with verticalization on the downtown zone. Anyway, the intention to reduce the impact caused by these processes must be planned in a more embracing context. Project elaboration must consider local climate and urban context, just as the environmental impacts of those on neighboring buildings and on open spaces. The idea of preserving skylines already consolidate, avoiding tall buildings, can be an alternative to minimize shading impacts.

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Jreissati, Wadih J. (Wadih Joseph) 1980. "Counterterrorism civil engineering design." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29555.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003.
Includes bibliographical references (leaf 51).
Because of the increasing concern about terrorist attacks, engineers have shown a substantial interest in making buildings safer for people. In order to come up with the most adequate design, experts have to carefully define the level of risk on the new structure, since people don't want to live in bunker-like buildings. Then, a good understanding of explosive devices will be a major help to keep the damage localized, preventing the overall collapse of the structure which can cause a lot more deaths than the explosion itself. The first and most important parameter is to secure the building's perimeter by increasing the standoff distance or by using security devices such as gates or even bollards around the building; careful site planning is essential and it costs a loss less when accounted for early in the design phase. Also, a wise choice of construction materials will mitigate blast effects; windows, doors, HVAC and firefighting systems should be designed to save lives and to not cause more injuries! Finally, the major driver for a successful blast protection is designing redundancies to carry the additional loads imposed by an explosion; structural members will therefore work as mediators for alternate load paths in the case of damage of their neighboring members.
by Wadih J. Jreissati.
M.Eng.

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Carvalho, Adrieli Cristina Vieira de. "Proposta de modelos de escritórios para gestão de projetos de arquitetura e engenharia para construções sustentáveis em IFES." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/3826.

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Made available in DSpace on 2015-03-26T13:28:32Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1080452 bytes, checksum: db6124f7a0ffaa0cda654d1352db934e (MD5) Previous issue date: 2014-02-03
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Most studies dealing with the issue of managing architectural and engineering have as its object of study the project management and private works of architecture. The public sector, such as academic institutions, have an important role in construction, but it is rarely analyzed in the work area. With the expansion of their campi, it has been observed most of the projects developed in the IFES have been outsourced. One reason for this is the fact that institutions often do not have a project team trained, prepared and structured enough to answer the demands of project. Moreover, it is observed that the units trying to develop their projects have had recurring management problems that embrace throughout the design process to work. It is associated with the increasing demand of the construction supply chain to adopt methodologies for the development of sustainable buildings. In view of the above facts, the objective of this research is to identify the factors conditions and procedures for proposing a model for the structuring of a Project Management Office (PMO) driven to sustainable projects in IFES. For this, we attempted to through a literature review and survey of multiple mini‐cases basis for the proposal of three reference models for the structure and operation of PMO. As a main result, it is concluded that the adoption of a systemic vision and understanding of the building design process from product life cycle are essential for the development of such projects.
A maioria dos trabalhos que tratam da questão da gestão de projetos de arquitetura e engenharia tem como objeto de estudo a gestão de projetos e obras de arquitetura privadas. O setor público, como por exemplo, as instituições universitárias, tem importante papel na construção civil, mas raramente é analisada pelos trabalhos na área. Com a expansão dos seus campi, tem‐se observado que a maioria do projetos de AEC desenvolvidos nas IFES tem sido terceirizados. Uma das razões para isso é o fato de que essas instituições muitas vezes não possuem uma equipe de projetos treinada e preparada, e com estrutura suficiente para atender as demandas de projetos. Além disso, observa‐ se que as unidades que tentam desenvolver seus projetos têm tido problemas recorrentes de gestão, que perpassam por todo o processo de projeto até a obra. Associa‐se a isso ainda, a crescente demanda da cadeia produtiva da construção em adotar metodologias para o desenvolvimento de construções sustentáveis. Em virtude dos fatos mencionados, o objetivo da presente pesquisa é identificar os fatores, requisitos e procedimentos para propor um modelo para a estruturação de um Escritório de Gerenciamento de Projetos (EGP) direcionado a projetos de AEC sustentáveis em IFES. Para isso, buscou‐se através de pesquisa bibliográfica e de levantamentos de múltiplos minicasos embasamento para a proposição de três modelos referenciais para a estruturação e operação do EGP. Como principal resultado, conclui‐se que a adoção da visão sistêmica e do entendimento do processo de projeto de edificações a partir do ciclo de vida do produto são essenciais para o desenvolvimento de projetos dessa natureza.

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Cox, Jonathan Peter. "Hydrometeorological aspects of drought management." Thesis, University of Salford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386429.

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Wardle, Gavin Roger. "Aspects of the drainage process in soils." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/23605.

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The initial portion of this thesis contains a review of basic theory. An experimental programme was also undertaken to measure soil parameters; and to observe heads and seepage rates during transient flow conditions in experiments. These experimental values were compared with results from finite element calculations. It was necessary for the candidate to devise a system for modifying an existing main-frame finite element package (ADINAT) in order to cope with the transient partly saturated draining state which exists above a falling water table. Good agreement was found between observed and computed transient heads. The experimental work of other investigators was also analysed by using this Finite Element program, and again good agreement was found between observed and computed transient conditions. It was decided in conjunction with the supervisor to limit this thesis to two-dimensional flow in the vertical plane.

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Chestnutt, Brian James. "Design aspects of multicable suspension bridges." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317107.

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Egeröd, Jens, and Emma Nordling. "Strategic Supplier Evaluation - Considering environmental aspects." Thesis, Linköpings universitet, Logistik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-63197.

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This study aims at presenting a strategic supplier evaluation model that can assist Cederroth in strategic supplier selection and give indications on potential areas for strategic supplier development. The evaluation model aims at assessing supplier performance also with respect to environmental aspects. The final model has been developed through five steps, five models, with starting point in a theoretical review and basic empirical data. Following the model was developed through four iterations of workshops, interviews, weighting and case studies. The final model includes 7 criteria categories and 41 criteria whereas one category including 7 criteria assesses a supplier’s environmental performance.

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Koziara, Tomasz. "Aspects of computational contact dynamics." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/429/.

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This work summarises a computational framework for dealing with dynamic multi-body frictional contact problems. It is in fact a detailed account of an instance of the Contact Dynamics method by Moreau and Jean. Hence the title. Multi-body systems with contact constraints are common. Some of them, such as machines or arrangements of particulate media, need to be predictable. Predictions correspond to approximate solutions of mathematical models describing interactions within such systems. The models are implemented as computational algorithms. The main contributions of the author are in an improved time integration method for rigid rotations, and in a robust Newton scheme for solving the frictional contact problem. A simple and efficient way of integrating rigid rotations is presented. The algorithm is stable, second order accurate, and in its explicit version involves evaluation of only two exponential maps per time step. The semi-explicit version of the proposed scheme improves upon the long term stability, while it retains the explicitness in the force evaluation. The algebraic structure of both schemes makes them suitable for the analysis of constrained multi-body systems. The explicit algorithm is specifically aimed at the analysis involving small incremental rotations, where its modest computational cost becomes the major advantage. The semi-explicit scheme naturally broadens the scope of possible applications. The semismooth Newton approach is adopted in the context of the frictional contact between three-dimensional pseudo-rigid bodies, proposed by Cohen and Muncaster. The Signorini-Coulomb problem is formulated according to the formalism of Contact Dynamics. Hybrid linearisation, parameter scaling and line search techniques are combined as the global convergence enhancements of the Newton algorithm. Quasi-static simulations of dry masonry assemblies exemplify performance of the presented framework.

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Charnock, Thomas W. "GIS linked environmental process models." Thesis, Aston University, 1997. http://publications.aston.ac.uk/13272/.

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In recent years there has been a great effort to combine the technologies and techniques of GIS and process models. This project examines the issues of linking a standard current generation 2½d GIS with several existing model codes. The focus for the project has been the Shropshire Groundwater Scheme, which is being developed to augment flow in the River Severn during drought periods by pumping water from the Shropshire Aquifer. Previous authors have demonstrated that under certain circumstances pumping could reduce the soil moisture available for crops. This project follows earlier work at Aston in which the effects of drawdown were delineated and quantified through the development of a software package that implemented a technique which brought together the significant spatially varying parameters. This technique is repeated here, but using a standard GIS called GRASS. The GIS proved adequate for the task and the added functionality provided by the general purpose GIS - the data capture, manipulation and visualisation facilities - were of great benefit. The bulk of the project is concerned with examining the issues of the linkage of GIS and environmental process models. To this end a groundwater model (Modflow) and a soil moisture model (SWMS2D) were linked to the GIS and a crop model was implemented within the GIS. A loose-linked approach was adopted and secondary and surrogate data were used wherever possible. The implications of which relate to; justification of a loose-linked versus a closely integrated approach; how, technically, to achieve the linkage; how to reconcile the different data models used by the GIS and the process models; control of the movement of data between models of environmental subsystems, to model the total system; the advantages and disadvantages of using a current generation GIS as a medium for linking environmental process models; generation of input data, including the use of geostatistic, stochastic simulation, remote sensing, regression equations and mapped data; issues of accuracy, uncertainty and simply providing adequate data for the complex models; how such a modelling system fits into an organisational framework.

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Radford, Todd C. (Todd Craig) 1977. "Wireless nodal sensing for civil engineering systems." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/85747.

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Sørum, Lars. "Environmental aspects of municipal solid waste combustion." Doctoral thesis, Norwegian University of Science and Technology, Norwegian University of Science and Technology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1488.

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Ikkatai, Koji. "Balancing financial and strategic aspects of real property portfolio management." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/45697.

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Harrison, Kenneth Watson. "Environmental and Water Resources Decision-Making Under Uncertainty." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-06042002-150804/.

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"Decision-making under uncertainty" is an important area of study in numerous disciplines. The variety of quantitative methods that have been proposed to address environmental and water resources problems reflects the importance of this subject. In a review of the literature, methods were compared and contrasted and promising areas for future research were identified. Conclusions drawn from the review were that 1) large gains may be realized from cross-disciplinary research, 2) significant benefits may be realized from considering uncertainty, 3) advanced algorithms?probabilistic search methods and efficient methods for Bayesian analysis?and increased computing power should greatly extend the applicability of existing methods, and 4) in particular, decision-theoretic methods that have wide application for sequential decision-making. A new decision-theoretic method, Bayesian programming (BP), was developed that takes advantage of the increased computing power and improvements in Bayesian analysis methods. The method has wide applicability, suitable for problems in which there is 1) uncertainty in the modeling, 2) stochastic behavior in the systems that are modeled, 3) the possibility to reduce uncertainty through data collection, and 4) the opportunity for a recourse decision after a period of data collection. The approach combines systematic search methods (mathematical programming) and Bayesian statistical analysis techniques (Markov chain Monte Carlo) in a decision analysis framework. The BP method is tested with application to a hypothetical, but realistic river basin management problem, using real data from the much-studied Athabasca River in Alberta, Canada. The management problem involves balancing the objectives of pulp mill development and water quality protection (dissolved oxygen). Results from application of the BP method were compared with those applying other methodologies. Examination of the results indicated that the BP method is a practical method worthy of additional research. Ultimately, it is hoped, this research will lead to computer-based tools that will improve environmental and water resources decision-making.

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Gopinath, Rakesh. "Concrete carbonation prediction for varying environmental exposure conditions." Doctoral thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/32700.

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The Durability Index (DI) approach has been developed in South Africa, in order to improve the durability performance of reinforced concrete structures. The DI approach is based on durability index tests, which are linked to transport mechanisms related to particular deterioration processes (Alexander et al., 1999a). Carbonation of concrete is governed, inter alia, by the microstructure and the transport characteristics of the concrete. A carbonation model with permeability coefficient (k) from the Oxygen Permeability Index (OPI) test as the key material variable was developed by Salvoldi (2010) using accelerated carbonation test data. The main aim of this research is to further develop the carbonation model by adopting the modelling framework of Salvoldi (2010) using natural carbonation data. For the experimental work, a total 48 different concrete mixes were produced by with different water: binder ratios (w/b), cement types, cement extender (addition) type and curing regime. The OPI test was conducted on all the concretes, and their corresponding permeability coefficients were determined. A set of 48 concrete specimens were exposed to five different sites for natural carbonation, and carbonation depths were measured periodically. Based on the modelling framework of Salvoldi (2010) and using the natural carbonation data between 150- 850 days, a model predicting the depth of natural carbonation was developed. However, in the case of concrete exposed to rain, drying/wetting is a major factor influencing the rate of carbonation. Therefore, the carbonation model was further modified taking into account the influence of drying/wetting cycles, by coupling it with a moisture model. For the development of the moisture model, the concrete specimens were exposed to a laboratory environment maintained at constant temperature and relative humidity (RH). The internal RH of the concrete specimens at varying depth was measured at different time intervals. Based on the measured RH data, the moisture model was also developed with ‘k' from the OPI test as the key input parameter. The moisture model was then coupled with the carbonation model developed. This provides an integrated and powerful solution for predicting carbonation of concrete both sheltered and exposed to rain by using only one main material input parameter ‘k', which is one of the major contributions of this research.

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Bush, Sarah 1973. "Integrating engineering education." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47457.

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Fayad, Philippe H. (Philippe Habib). "Aspects of the volumetric and undrained behavior of Boston Blue Clay." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14633.

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Vink, Dustin. "Aspects of bond graph modelling in control." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/1140/.

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Dissertations / Theses on the topic 'Environmental aspects of Civil engineering'

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