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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Environmental and Cost impact Analysis of Materials and Assemblies in Building Construction

Nirmal, Deepika 30 March 2012 (has links)
One of the new trends in the building construction industry is designing for environmental-friendly buildings, a.k.a. Green Buildings. Planners and designers are therefore trying to accommodate these new environmental practices into existing design criteria. Selection of building materials is one of the key decisions need to be made by building designers. However, due to the strong influence of costs on the building industry, making material-selection decisions solely based on their environmental impacts could be both inadequate and impractical. These factors therefore complicate the building design process, especially pertaining to material selection. Accordingly, the present study is aimed at providing much needed support to the decision-making process of residential building design. To this end, the study evaluates and analyzes the environmental and cost impacts of several building assemblies and material alternatives for the building exterior walls. The Technique of Order Preference Similar to Ideal Solution (TOPSIS) is used to evaluate and rank different material alternatives used in walls based on their environmental impacts. In addition, the environmental data used in this study were extracted from commonly used databases that considered the lifecycle impacts of different residential building materials and assemblies. The environmental and cost impacts of several exterior wall assemblies are then aggregated for different building material alternatives to allow for an objective comparison of these assemblies and facilitate proper building design decision- making. The study results show that wood and exterior insulation finishing system (EIFS) provided the best environmental performance of wall structural and wall finishing materials, respectively. This research is expected to prove useful in supporting building design decision- making. In addition, this research can improve pre-construction estimation and support screening of building materials.
2

Impacts des approches géomatiques dans les organisations de l'archéologie

Costa, Laurent 12 January 2010 (has links)
Ce travail traite de l’impact des systèmes d’information géographique (SIG) dans les organisations de la recherche archéologique. L’examen de projets puisés dans les différents contextes organisationnels de la recherche archéologique nationale (services archéologiques des collectivités territoriales, institut national de recherche archéologique préventive, ministère de la Culture, organismes de recherche et d’enseignement supérieur), nous a permis de dégager les singularités et les permanences des pratiques liées aux SIG. Cette approche est suivie par la mise en oeuvre et l’analyse de dix expérimentations réalisées avec les équipes archéologiques du service départemental d’archéologie du Val-d’Oise (SDAVO) et celles de l’UMR 7041 Archéologies et Sciences de l’Antiquité, qui nous ont permis de réfléchir sur les modalités du développement d’une base de données géographiques appliquée à la recherche archéologique.Cette double démarche montre qu’il est pertinent de questionner les méthodes et les techniques formelles de mise en œuvre des outils afin que soit pris d’avantage en compte la nature profonde des différents acteurs avec leurs rationalités et leurs perceptions. Elle met en exergue l’aspect stratégique des dispositifs de mutualisation et de partage des matériels, des données et des compétences.L’utilisation des SIG en archéologie doit se concevoir selon un double processus : intégration pour le développement de modèles de données permettant d’assimiler les spécificités organisationnelles et métiers de chacun ; généralisation par l’utilisation de standards dont la constitution est un des problèmes qui reste à résoudre. / This work deals with the impact of the geographical information systems (GIS) in the french institutions of archaeological research.The examination of projects drawn from various contexts (archaeological services of regions with a measure of autonomy, national institute of preventive archaeological research(INRAP), Ministry of Cultural Heritage, University and institute of researchs), allowed us to kick away the peculiarities and durabilities of the practices connected to GIS.This first approach is followed by the implementation and the analysis of ten experiments realized with the archaeological teams of the departmental service of archaeology of Val-d'Oise (SDAVO) and those of the UMR 7041 Archaeologies and Sciences of Antiquity, which allowed us to think about the modalities of the development of a geographical database applied to the archaeological research.This double initiative shows us that it is relevant to question the methods and the formal techniques of implementation of tools so that is taken into account favor the deep nature of the various actors with their rationalities and their perceptions. It highlights the strategic aspect of the devices of mutualization and sharing of the equipments, datas and skills.The use of the GIS in archaeology has to conceive according to a double process: integration for the development of models of data allowing to assimilate the organizational specificities and the professions by each; generalization by the use of standards which the constitution is one of problems which remains to resolve.
3

The impacts of technology on global unconventional gas supply

Yanty, Evi 02 June 2009 (has links)
As energy supplies from known resources are declining, the development of new energy sources is mandatory. One reasonable source is natural gas from unconventional resources. This study focus on three types of unconventional gas resources: coalbeds, tight sands, and shales. Whereas these resources are abundant, they have largely been overlooked and understudied, especially outside of North America. New technologies, including those needed to unlock unconventional gas (UCG) resources, have been acknowledged to be the most significant factor in increasing natural gas supply in the United States. This study evaluates advances in critical technology that will most likely increase supply the most. Advanced technology is one of the main drivers in increasing unconventional natural gas production, as observed in the United States, Canada, and Australia. 3D seismic, horizontal drilling, multilateral completion, water and gel based fracturing, coiled tubing rig, enhanced recovery, and produced water treatments are current important technologies critical in developing unconventional gas resources. More advanced technologies with significant impacts are expected to be available in the next decades. Fit-to-purpose technology reduces the cost to recover gas from unconventional resources. The better the unconventional gas resources are characterized, the better we can tailor specific technology to recover the gas, and less cost are needed. Analogy assumption is a good start in deciding which critical technology to be transferred to undeveloped unconventional reservoirs. If the key properties of two unconventional gas basins or formations are more or less similar, it is expected that the impact of certain technology applied in one basin or formation will resemble the impact to the other basin or formation.
4

Mixed-phase clouds, thin cirrus clouds, and OLR over the tropics: observations, retrievals, and radiative impacts

Lee, Joonsuk 02 June 2009 (has links)
The tropics is a very important region in terms of earth’s radiation budget because the net radiative heating is largest in the tropics and that surplus energy is redistributed by the circulations of oceans and atmospheres. Moreover, a large number of clouds are formed by deep convection and convergence of water vapor. Thus, it is very important to understand the radiative energy balance of the tropics and the effect of clouds on the radiation field. For mixed-phase clouds, error analyses pertaining to the inference of effective particle sizes and optical thicknesses are performed. Errors are calculated with respect to the assumption of a cloud containing solely liquid or ice phase particles. The analyses suggest that the effective particle size inferred for a mixed-phase cloud can be underestimated (or overestimated) if a pure liquid phase (or pure ice phase) is assumed for the cloud, whereas the corresponding cloud optical thickness can be overestimated (or underestimated). The analyses of optical depth and fraction of occurrence for thin cirrus clouds showed that about 40% of pixels flagged as clear-sky contain detectible thin cirrus clouds. The regions of high occurrence and large optical depth located around deep convection showed seasonal variations. The thin cirrus clouds occur more frequently with larger optical depth in the northern (southern) hemisphere during spring and summer (autumn and winter). The net cloud radiative forcing by thin cirrus clouds is positive at the top of atmosphere and is negative at the bottom of atmosphere. The difference in OLR between measurement and model is 4.2 Wm-2 for September 2005. The difference is smaller in moist regions and larger in drier regions. OLR increases with increasing surface temperatures up to 300 K but decreases at surface temperatures larger than 300 K due to the strong absorption of increased water vapor. In summary, if the surface temperature is lower than the threshold of convection (300 K), temperature is a dominant factor in OLR and if the surface temperature is larger than 300 K, OLR is strongly influenced by water vapor.
5

The impacts of technology on global unconventional gas supply

Yanty, Evi 02 June 2009 (has links)
As energy supplies from known resources are declining, the development of new energy sources is mandatory. One reasonable source is natural gas from unconventional resources. This study focus on three types of unconventional gas resources: coalbeds, tight sands, and shales. Whereas these resources are abundant, they have largely been overlooked and understudied, especially outside of North America. New technologies, including those needed to unlock unconventional gas (UCG) resources, have been acknowledged to be the most significant factor in increasing natural gas supply in the United States. This study evaluates advances in critical technology that will most likely increase supply the most. Advanced technology is one of the main drivers in increasing unconventional natural gas production, as observed in the United States, Canada, and Australia. 3D seismic, horizontal drilling, multilateral completion, water and gel based fracturing, coiled tubing rig, enhanced recovery, and produced water treatments are current important technologies critical in developing unconventional gas resources. More advanced technologies with significant impacts are expected to be available in the next decades. Fit-to-purpose technology reduces the cost to recover gas from unconventional resources. The better the unconventional gas resources are characterized, the better we can tailor specific technology to recover the gas, and less cost are needed. Analogy assumption is a good start in deciding which critical technology to be transferred to undeveloped unconventional reservoirs. If the key properties of two unconventional gas basins or formations are more or less similar, it is expected that the impact of certain technology applied in one basin or formation will resemble the impact to the other basin or formation.
6

Constraints to Continued Rock Climbing Participation in the Southern Illinois Region

Pendergast-White, Ian Michael 01 December 2010 (has links)
AN ABSTRACT OF THE THESIS OF IAN M. PENDERGAST-WHITE, for the Master of Science degree in FORESTRY, presented on *July 7, 2010, at Southern Illinois University Carbondale. TITLE: CONSTRAINTS TO CONTINUED ROCK CLIMBING PARTICIPATION IN THE SOUTHERN ILLINOIS REGION MAJOR PROFESSOR: Dr. Jean Mangun In recent years rock climbing has seen dramatic increases in the number of participants nationwide. Climbing opportunities in southern Illinois are expected to become popular climbing destinations as the area becomes better publicized. The high quality sandstone, aesthetic features, and easy access help to ensure that the number of rock climbers coming to the region will only continue to grow. As has been described in the literature with other "new" activities on public lands, concern from land management agencies likewise continues to grow in direct correlation with the increasing numbers of climbers. Although there are literally dozens of published articles in the sports medicine literature about injuries from rock climbing and physiological responses, there is a surprising lack of research on the activity itself. The present study applies a qualitative approach to collect baseline data that characterizes regional climbing participants and their concerns before resource allocation issues develop further. Twenty climber interviews, two climber focus groups, and four key informant interviews with managers were conducted and data analyzed for emerging themes. Findings from the analysis suggest: although a strong sense of community and dedication to the activity exists within the climbing user group, climbers express concern that their activity lacks stature as a legitimate resource-based recreation activity among other stakeholder groups. Differing perceptions of the environmental impacts associated with climbing persist that lead to climbing access issues. Creation of local climbing organizations, such as the Illinois Climbers Association, can play a pivotal role in promoting progressive collaboration among stakeholders groups, which will be necessary to resolve these issues and better integrate rock climbing into the mix of accepted recreation activities in the southern Illinois region.
7

INVESTIGATING THE EFFECTS OF NON-CONSUMPTIVE RECREATION ON NON-BREEDING WATERFOWL IN SOUTHERN ILLINOIS

Gilbert, Christopher 01 December 2022 (has links)
Human presence and recreational activities can negatively impact wildlife. Due to the popularity of human recreation along bodies of water, waterfowl populations are frequently impacted. Non-consumptive recreation can impact waterfowl by leading to unnecessary expenditure of energy, and exclusion from important feeding areas. These consequences can ultimately impact overwintering and migratory survival as well as breeding success. With recreational demands expected to increase, it is important for waterfowl and habitat managers to understand the immediate and additive impacts of recreational activities and how landscape and seasonal covariates can influence these impacts. Additionally, the presence of researchers and the popular methods used to monitor waterfowl themselves can be intrusive. As advances have been made in optics and other monitoring technologies, wildlife researchers have implemented new methods to minimize disturbance to their study organisms as well as increase efficiency and access remote areas. I conducted waterfowl distribution and behavioral surveys across 13 sites in southern Illinois during the non-breeding season (Oct-Feb) of 2020-2021. I also tested the efficacy of an affordable remote video surveillance systems compared to in-person waterfowl counts to monitor distribution and abundance of waterfowl. In person counts and proportion of behaviors were recorded every 5 minutes as well as before and after a given disturbance to 1) assess the impacts of specific recreational activities on waterfowl and 2) examine patterns in daily site usage, distribution and behavior in relation to daily numbers of disturbances events. Remote video surveillance derived counts were inaccurate and rarely detected birds when present (n=8 out of 5,754 total comparisons). When waterfowl were detected, counts often were less than the in-person counts (n=6). Major reasons for a lack of detection were limited camera resolution and field of view, weather and user error. Boating and lawn maintenance/construction had the greatest immediate impacts on waterfowl distribution and proportions of flight response. Exercise, wildlife observation, and fishing also had significant immediate impacts on waterfowl behavior and distribution but to a lesser extent. When looking at daily patterns, increasing the daily number of water-based disturbances led to lower rates of site usage by waterfowl and increased daily rates of evasive behaviors at the expense of feeding and resting. Increases in land-based disturbances (exercise, wildlife observation, and fishing) had no significant impact on daily patterns of local site usage and behaviors, suggesting birds are capable of acclimation to terrestrial recreation. Vehicular traffic had no effect on any immediate responses or daily patterns in site usage, distribution or behavior. Covariates such as cover type, urbanization, hunting season, distance from shore, and buffer size influenced how impactful non-consumptive recreation is on waterfowl. Some of the most significant findings were that larger buffer zones often minimized the immediate and additive impacts of terrestrial recreation, and birds were less likely to flee disturbance events during the hunting season. Although recreation overall does impact waterfowl, land managers can still provide opportunities for many terrestrial recreational activities, specifically by having trails and other areas of recreation further from waterfowl habitat. Partial and temporary closures to high impact activities like boating may be needed. Also, when studying waterfowl populations, remote video surveillance systems do not appear to be a viable alternative to in-person waterfowl monitoring; however, with more time for technology to improve, this method may need to be revisited.
8

Floods in Southeast Asia: A Household Welfare Priority

Le, Thi Ngoc Tu 15 February 2019 (has links)
No description available.
9

Comportement de matériaux carbonés sous sollicitations dynamiques intenses : analogie entre irradiations lasers et impacts hypervéloces / Behaviour of carbon materials under intense dynamic loading : analogy between laser irradiations and hypervelocity impacts

Bertrand, Aubert 26 November 2018 (has links)
L’étude des impacts hypervéloces (IHV) est essentielle dans de nombreux domaines tels que l’aérospatial, la cosmologie ou l’armement. Pour les reproduire en laboratoire, il est usuel d’utiliser des lanceurs à gaz ou à poudre. Toutefois, ce type de moyen se limite à des vitesses d’impact de l’ordre de 10 km/s pour des projectiles millimétriques. Afin d’étudier des vitesses plus élevées, il faut se tourner vers des moyens alternatifs. Dans cette étude, nous démontrons qu’une analogie est possible entre irradiations laser et IHV. Pour parvenir à ce résultat, des données expérimentales ont été obtenues sur le lanceur HERMES et sur l’installation laser GCLT. Deux matériaux cibles ont été considérés : l’aluminium 6061-T6 et l’EDM3, un graphite poreux. Par simulation numérique, nous avons caractérisé spatialement et temporellement les champs de pression générés en surface des cibles par un projectile et par un laser. Cela nous a permis de proposer et de valider une procédure permettant de lier IHV et essais laser. Pour finir, une campagne expérimentale été réalisée sur l’installation laser du LULI2000 afin d’étudier des vitesses d’impact pouvant atteindre 32 km/s. / The study of hypervelocity impacts (HVI) is essential in many fields such as aerospace, cosmology or defense. To reproduce them in laboratory, it is usual to use gas or powder launchers. However, this type of facility is limited to impact velocities under 10 km/s for projectiles of millimeter size. In order to study higher velocities, it is necessary to consider alternative means. In this study, we demonstrate that an analogy is possible between laser irradiations and HVI. To do this, experimental data were obtained on the HERMES launcher and the GCLT laser facility. Two target materials were considered: 6061-T6 aluminum and EDM3, a porous graphite. By numerical simulation, we spatially and temporally characterized the pressure fields generated on the surface of the targets by a projectile and a laser. It allowed us to propose and validate a procedure to link HVI and laser shots. Finally, an experimental campaign was carried out on the LULI2000 laser facility to study impact velocities up to 32 km/s.
10

Etude expérimentale et théorique de l'endommagement du graphite sous sollicitation dynamique - Application aux impacts hypervéloces / Expérimental and Theoretical Study of the Damaging of Graphite under Dynamic Loading - Application to Hypervelocity Impacts

Seisson, Gabriel 10 October 2014 (has links)
Les matériaux composites sont très utilisés dans diverses applications et sont parfoissoumis à des impacts hypervéloces (IHV), notamment dans le domaine spatial. La taille des impacteursétant proche de celle des torons de fibres, les simulations mésoscopiques ont tout leurintérêt mais nécessitent des modèles numériques aboutis pour chaque sous-Constituant. Le graphiteétant souvent utilisé comme matrice ou fibres, nous avons étudié son comportement dynamique.Ainsi, des expériences de pénétration et de cratérisation ont été menées sur un isographite poreux.L’analyse post-Mortem des cibles, associée à des calculs d’ordre de grandeur, apporte un éclairagenouveau sur la phénoménologie des impacts et fournit des renseignements utiles à la simulationnumérique. Un modèle pour matériaux poreux et fragiles, implémenté dans un code de dynamiquerapide, est utilisé. Basé en partie sur des propriétés statiques, il a été progressivement testé sur deschocs plans. Son utilisation pour la simulation des IHV donne de bons résultats. Toutefois, il convenaitde le valider en s’affranchissant du comportement du projectile. Pour cela, une campagne dechocs lasers a été menée. Des diagnostics in-Situ ont été utilisés et leur corrélation avec des analysespost-Mortem a permis l’identification de différents modes d’endommagement des cibles. Finalement,bien que l’équivalence entre IHV et chocs lasers ne soit pas démontrée, ces derniers se sont montréscomplémentaires en suggérant de futures évolutions du modèle numérique. / Composite materials are widely used in various applications and may be submittedto hypervelocity impacts (HVI), such as in the aerospace field. The size of the impactors beingclose to that of a strand of fibers, mesoscopic simulations are of great interest but they need reliablenumerical models for each meso-Constituent. Graphite often being used as fiber or matrix,we studied its dynamic behavior. Penetration and craterization experiments have been conductedonto porous isotropic graphite. Post-Mortem analysis of targets, associated to order-Of-Magnitudecalculations, sheds a new light on the phenomenology of impacts and brings useful informationfor numerical simulation. A model for porous and brittle materials, implemented into a hydrocode,is used. Partially based on static mechanical properties, it has been progressively tested on planeshocks. Its use for simulating HVI gives satisfying results. Nevertheless, it was necessary to validateit by disregarding the projectile behavior. In that purpose, a campaign of laser-Driven shocks hasbeen conducted. In-Situ diagnostics have been simultaneously used and their correlation with postmortemanalysis allowed the identification of different damaging regimes of the targets. Finally,although the equivalence between HVI and laser-Driven shocks is not proved, the latter turned outto be complementary, suggesting the future evolutions of the numerical model.

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