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1

Lee, Jong Min. „Engineering the Environment: Regulatory Engineering at the U.S. Environmental Protection Agency, 1970-1980“. Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/51564.

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My dissertation addresses how engineers, scientists, and bureaucrats generated knowledge about pollution, crafted an institution for environmental protection, and constructed a collective identity for themselves. I show an important shift in regulators\' priorities, from stringent health-based standards to flexible technology-based ones through the development of end-of-pipeline pollution control devices, which contributed to the emergence of economic incentives and voluntary management programs. Drawing on findings from archival documents, published sources, and oral history interviews, I examine the first decade of the EPA amid constant organizational changes that shaped the technological and managerial character of environmental policy in the United States. Exploring the EPA\'s internal research and development processes and their relationship with scientific and engineering communities sheds light on how the new fields of environmental engineering and policy were co-produced in the 1970s. I argue that two competing approaches for environmental management, a community health approach and a control technology approach, developed from EPA\'s responses to bureaucratic, geographical, and epistemic challenges. I focus on researchers and managers from the Office of Research and Development at Research Triangle Park, North Carolina, as they were engaged in (1) controversy about integrated aerometry and epidemiology research intended to correlate air pollution and health, (2) intra-agency debate about the government\'s responsibility for introducing catalytic converters for tailpipe emissions reduction and responding to the potential environmental and social consequences, and (3) inter-agency activities for the demonstration of scrubbers for smokestack emissions and further application of the control technology approach in energy-related environmental problems. My principal conceptual contribution is "regulatory engineering." I define regulatory engineering as an approach to sociotechnical problems in which engineering practices are incorporated into regulatory and organizational changes, which in turn influences technical knowledge and identity formation. As EPA activities became closely associated with energy and economic issues toward the end of the 1970s, I argue that engineers took the initiative in demonstrating and evaluating control technologies for pollution abatement and energy development, scientists carefully studied environmental and health effects of these technologies, and regulators set up pollution standards and attainment deadlines accordingly. Studying the co-production of knowledge, institution, and identity through the lens of regulatory engineering helps us to understand technoscientific and managerial aspects of environmental governance beyond the 1970s EPA where technical feasibility considerations, economic incentives, and cooperative management expanded into legislation and regulation.
Ph. D.
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2

Williams, Philip R. L. „Environmental Engineering: Towards the New Engineer“. Thesis, Griffith University, 2000. http://hdl.handle.net/10072/365623.

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Environmental engineering is a relatively new engineering discipline. The engineering profession increasingly recognises the importance of engineers moving from their traditional stereotypical technical focus and becoming broader skilled and more responsive to society's needs, particularly regarding the environment. This is often encapsulated as the new engineer. Environmental engineers should be well placed to make a significant contribution to this goal. The nature of engineers and engineering is briefly discussed before tracing the evolution of environmental engineering. This new branch of engineering has evolved from the earlier dominance of sanitary or public health engineering and now incorporates a broader, holistic approach to the solution of environmental issues. A literature review is presented on society~s awareness and concern with the environment. This leads to an investigation of the relationship between engineers and the environment. A review of environmental engineering education follows. The education of engineers to improve their environmental credentials is contentious. A common theme is that all engineers require a better environmental education. However, there is less consensus regarding the need for separate environmental engineering degrees at undergraduate level. Despite this, environmental engineering degrees have proliferated in Australia in the past decade. Yet little is known about the graduates and their transition into an engineering profession which is largely founded in traditional engineering values. This research addresses the lack of knowledge about environmental engineers. Using a number of concepts from sociology, particularly professional socialisation, a theoretical framework was developed to suggest what environmental engineers may experience both as students and in professional practice. This theoretical framework was tested using a case study of forty-four recent graduates from the School of Environmental Engineering's undergraduate degree in environmental engineering at Griffith University in Brisbane, Australia. This environmental engineering degree is considered unique in this country because of its breadth and diversity of subject material, which is underpinned by the host school's location in the Faculty of Environmental Sciences. This contrasts with the common approach of either slightly modifying existing civil engineering degrees to produce an environmental strand or creating a hybrid environmental engineering degree through combinations of other engineering programmes. In both these cases, the environmental engineering is normally located in an engineering faculty and is thus more influenced by traditional engineering values. The research in this thesis is qualitative in nature. This approach was adopted to ensure a rich picture emerges of the professional socialisation of enviromnental engineers. The data presented are based on interviews with the graduate environmental engineers and follows the graduates chronologically through university and into professional practice. Environmental engineering students enter university with considerable diversity of knowledge, interest and commitment. The degree programme exerts a strong socialising influence in raising environmental awareness and capabilities. However, the outcome is not uniform and a number of socialisation failures can be identified, particularly where graduates are concerned about their identity and lack confidence as engineers at the end of their studies. The path to professional socialisation as environmental engineers is further influenced by the widespread lack of recognition of the qualifications and capabilities of environmental engineers in the profession and employment. Professional socialisation also varies considerably with the diversity of employment situations. In general, the process of organisational socialisation into the norms of an employment culture is stronger than the socialising influences of the profession. Socialisation is also affected by individualism. Thus, overall there are a spectrum of professional socialisation successes and failures. Environmental engineering is plagued by considerable uncertainty as to its nature. This is apparent throughout the engineering profession and employer organisations. This uncertainty has a significant impact on environmental engineers and consequently many are unsure regarding their identity as engineers. Despite the uncertainties regarding identity and professional socialisation, the generalist skills, environmental commitment and capabilities, and social responsiveness of many of the environmental engineering graduates typify the attributes of the new engineer. A minority could not be considered as meeting these attributes, particularly where they identify more strongly with traditional engineering values. However, on balance, it is evident that environmental engineers are making a significant contribution to the paradigm change that the engineering profession must make to better reflect societ~s needs and aspirations. The thesis concludes with a range of recommendations designed to indicate areas of further research to complement and extend this study.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental Engineering
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3

Robertson, Peter K. J. „Applications of engineering for environmental sustainability“. Thesis, University of Ulster, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625479.

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The approach to addressing many environmental problems requires a strong foundation in chemical science and engineering. A prime example is the developing subject of environmental engineering, where a multidisciplinary field is led by chemists and chemical engineers. This thesis presents a collection of research publications, which are of both an applied and multidisciplinary nature, primarily directed towards developing technology for energy and environmental sustainability. This has included the development of sensors for in-situ environmental monitoring and the application of nanocrystalline semiconductor photocatalysts for treatment of air, waste and potable waters. The development of laser processing methods for catalyst production and modification and the design and assessment of advanced photocatalytic reactors is also presented. Research on the reduction of carbon dioxide to fuel products is also considered. Real time in-situ sensors for environmental monitoring are an area that has seen a significant growth over the past twenty years. In this thesis, I detail my research into optical and electrochemical sensors for detection of organic chemicals and heavy metals in both the marine environment and in contaminated land. The other key research theme is the topic of water remediation using semiconductor photocatalysis. This has included treatment of industrial effluent, drinking water and water used in aquaculture. In particular, I have led research on the photocatalytic removal of cyanotoxins in water, a technique pioneered at RGU. These highly toxic chemical metabolites of cyanobacteria have been responsible for the deaths of animals and humans through ingestion of contaminated water.
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4

Long, Graham. „Engineering Doctorate (EngD) in Environmental Technology“. Thesis, University of Surrey, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310040.

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5

Luo, Jing. „Molecular modeling of sorption phenomena in environmental engineering“. Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280483.

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This research investigated the adsorption mechanisms of hydrophobic chlorinated contaminants in mineral micropores and on iron metal surfaces. Activated adsorption and desorption of trichloroethylene (TCE) in mineral micropores was studied using experimental and molecular modeling techniques. Adsorption of TCE on a silica gel adsorbent was measured using a frontal analysis chromatography technique at atmospheric and elevated fluid pressures. The results showed that the increase in pressure was able to rapidly induce the formation of a desorption resistant fraction. Grand Canonical Monte Carlo (GCMC) modeling was used to elucidate the nature of water and TCE behavior within silica micropores. TCE adsorption was energetically most favorable in pores that were minimally large enough to accommodate one TCE molecule. A molecular level study of the interactions between hydrophobic chlorinated contaminants and sediments was performed. GCMC simulations were preformed to investigate water and TCE adsorption in slit micropores confined by charged and uncharged silica surfaces. Gas-phase single-sorbate simulations with water or TCE were performed as well as mixture simulations of bulk water containing TCE at 1% of its saturation concentration. Aqueous-phase TCE at a concentration equal to 1% of its saturation concentration was able to completely displace adsorbed water in uncharged pores. In highly hydrophilic pores, TCE at this concentration was able to displace up to 50% of the adsorbed water. Metallic iron filings are becoming increasingly utilized as reactive agents for reductive dechlorination of solvents in contaminated groundwaters. This research also used molecular modeling to study chemical adsorption of TCE and PCE to iron surfaces. Quantum mechanical calculations were performed to determine the thermodynamic favorability and resulting structures for chemical adsorption of TCE and PCE to iron surfaces. Molecular mechanics modeling was used to study the effects of atomic hydrogen on the thermodynamic favorability for chemically adsorbed TCE and PCE. Because TCE and PCE react with iron surfaces, their adsorption to iron cannot be investigated experimentally. This makes molecular modeling approaches a useful complement to experimental investigations of chemical reaction phenomena.
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6

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

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7

Weng, Chi. „Software development for an environmental engineering analysis system“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39709.pdf.

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8

Lingegård, Sofia, Tomohiko Sakao und Mattias Lindahl. „Integrated product service engineering : factors influencing environmental performance“. Linköpings universitet, Industriell miljöteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72843.

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This paper aims to lead theoretical discussion regarding which IPSE (Integrated Product Service System) factors are expected to increase environmental performance of a life cycle compared to a traditional product sales business. Existing theories such as theory of product development, transaction cost theory and theory for risk management are used and the paper theoretically analyzes and identifies the following crucial characteristics; complexity of the product, uncertainty of offering, control of product operation, asymmetric information and scale of economy.
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9

Krausse, Sylvana. „A corpus-informed investigation into environmental engineering English“. Frankfurt, M. Berlin Bern Bruxelles New York, NY Oxford Wien Lang, 2007. http://d-nb.info/987579223/04.

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10

Markarian, Naro R. „Environmental control of vegetable storage environments“. Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31268.

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A large-scale experimental, state of the art storage facility was constructed on the Macdonald Campus of McGill University. This storage facility will serve as a tool to further investigate many of the laboratory experiments performed in agricultural and food science topics, by providing a representation of actual storage facilities in use in the industry today. The storage facility was fully instrumented to provide valuable data of the stored commodity and it's environment. A custom control software was developed with a user friendly graphical interface. This fully automated software allows data acquisition and control of temperature and relative humidity of the experimental storage facility.
Experiments were performed and the control software provided an adequate temperature and relative humidity control. The controller was based on a conventional PID or proportional, integral and derivative controller. To further improve the control of the storage facility, a novel multivariable PID controller was developed using enthalpy as the process variable, which encompasses both temperature and relative humidity. The novel controller was tested using a mathematical model developed. Simulations were performed comparing the performance of the novel multivariable controller to two other conventional controllers. The results demonstrate that the novel multivariable PID controller is capable of controlling temperature and relative humidity better than the other two conventional control techniques.
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11

Lindahl, Mattias. „Engineering Designers' Requirements on Design for Environment Methods and Tools“. Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-236.

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12

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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13

Hor, Joon Suk 1976. „Social interaction in collaborative engineering environments“. Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80156.

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14

Zoumprouli, Argyro. „Wind farm and environmental aerodynamics assessment using computational engineering“. Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/7212.

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The aim of this thesis is the application of computational engineering software for the study of wind resource assessment of a wind farm as well as for establishing the range of influence of different numerical and physical parameters, including turbulence modeling , surface roughness and wakes. Simulations were performed for a wind farm which is in operation since 2006, called Panachaiko, located at the west part of Greece and encompassing an energy capacity of 34.85 MW. Simulations were performed using three variants of the k-ε model. Moreover, the effects of surface roughness and wake on the efficiency of wind farm operation were investigated. Comparisons were performed between linear and non-linear computational fluid dynamics (CFD) modeling, in the framework of the available engineering (commercial) software. Both qualitative and quantitative assessment of the results is presented. The study revealed the dependence of the results on the CFD (linear vs non-linear) model employed. The results of the present study provide useful guidance regarding the applicability of CFD models for wing resource assessment.
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15

Singh, Shailendra. „Cell and peptide engineering environmental clean-up to bioprogramming /“. Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=26&did=1790236011&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1270076813&clientId=48051.

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16

Pasala, Jayaprakash 1975. „Information management in virtual engineering“. Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9364.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1999.
Includes bibliographical references (leaf 68).
Engineering projects are rapidly growing in size and complexity. Computers have aided in managing project growth and solving the complexity issues to some extent. Engineering design has moved from drawing board design to computer aided design. But the process of design has changed minimally. There is still a potential for using computers to improve the design process. Engineering design projects are increasingly often being implemented by more than one firm; it is often beneficial and even necessary to collaborate. The collaboration between geographically distant branches/firms has to be achieved, as the required expertise is normally never found in one place. This research takes a look at using available computer technology for improving the engineering design collaboration and to improve the process of design. The research also takes a look the potential problems that will be encountered in a collaboration project and how to overcome them. The International Standards Organisation (ISO) procedures still insist on the complete documentation in the form of manuals or in electronic form. This documentation procedure has its advantages but the basic disadvantage lies with fact that the documentation and design are viewed as two separate processes. This research proposes a method to integrate them. This project demonstrates the feasibility of knowledge capture in the design process to aid the design engineer. The project also demonstrates rapid application prototyping using the JAVA language.
by Jayaprakash Pasala.
S.M.
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17

Poolvoralaks, Suriyon. „Groupware system in construction engineering“. Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41365.

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18

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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Aguayo, Juan C. (Juan Carlos) 1964. „Financial engineering for BOT infrastructure projects“. Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9713.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 1999.
Includes bibliographical references (leaves 224-228).
The implementation of the Build-Operate-Transfer (BOT) model for the provision of infrastructure facilities in the United States constitutes a paradigm shift, and a recent innovation, in the delivery and financing of these socially and economically important projects. The main justification, for incorporating the BOT strategy as an alternative in the development of new infrastructure facilities, is the need to access private capital to leverage the insufficient government funds for the financing of these massive undertakings. A key factor contributing to the sustainability of the BOT approach as a viable procurement strategy for infrastructure projects, and providing a decisive competitive advantage to prospective private sector respondents interested in pursuing these ventures, is the expertise in financial engineering. As defined in this thesis, financial engineering is the systematic process that enables a private company to decide first in which BOT project to invest, and then to design the most cost-effective funding structure for financing the venture. This thesis proposes a formal procedure for the financial engineering and modeling of BOT infrastructure projects. Financial modeling, the cornerstone of the financial engineering process, involves the development of simplified scenarios, analytical tools and techniques that enable the objective evaluation of the economic attractiveness and financial viability of a BOT venture. After outlining the steps within the suggested financial modeling framework, a case study consisting of the Canada Confederation Bridge Project is presented. Acknowledging that the recommended financial models for BOT infrastructure projects are simplified illustrations of mammoth and complicated construction programs, this thesis also investigated some of the most important issues Associated with these types of investments to complement the quantitative analyses. This was accomplished through a literature review, and four mini case studies consisting of recent projects in the United States.
by Juan C. Aguayo.
S.M.
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20

Tatang, Menner A. „Direct incorporation of uncertainty in chemical and environmental engineering systems“. Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11760.

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21

Hunt, David Raymond. „A high school curriculum for a course in environmental engineering“. CSUSB ScholarWorks, 1999. https://scholarworks.lib.csusb.edu/etd-project/1516.

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22

Naito, Seiji 1969. „Strategic alliances of engineering & construction firms“. Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/10102.

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23

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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24

Hussein, Karim Mohie El Din 1972. „Communication facilitators for a distributed collaborative engineering environment“. Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/37787.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995.
Includes bibliographical references (leaves 90-93).
by Karim Mohie El Din Hussein.
M.S.
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25

Carlson, Randi A. (Randi Aileen) 1971. „Triblock polyampholyte solutions for environmental applications“. Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47597.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998.
Includes bibliographical references (leaves 55-60).
by Randi A. Carlson.
S.M.
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26

Higgins, Cheri Rochelle. „Ecosystem Engineering by Muskrats (Ondatra zibethicus) In Created Freshwater Marshes“. The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392109286.

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27

An, Siwen. „X-ray Fluorescence Spectrometry for Environmental Applications“. Licentiate thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39979.

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Heavy metal contamination in environmental applications is particularly important because of its potential impact on associated ecosystems and human health. At present, monitoring of heavy metals is usually done by taking and preparing samples for off-line laboratory measurements. X-ray fluorescence (XRF) analysis is a powerful and widely used tool for determining the elemental composition and concentration of chemical species in materials. This project is a feasibility study for the possibility of on-line XRF systems for continuousand direct analysis of industrial processes and environmental emissions. The feasibility of such measurements depends on the accuracy with which the concentration can be measured within a given response time. Therefore, this project is focused on investigating possible background suppression of the XRF spectrum. First, an XRF setup has been built, and its capability has been compared to a commercial scanning electron microscope with energy dispersive spectroscopy (SEM-EDS). The qualitative analysis and semi-quantitative analysis of heavy metal contamination in fly ash was performed and compared. Due to minimal sample preparation, the developed XRF system is suitable for in-situ measurements. A series of experiments was performed to optimize the signal-to-noise ratio of the spectra achieved from chromium contaminated liquid samples. The most significant factor turned out to be the primary X-ray source filter. Numerical simulation models have been developed in the Monte Carlo N-particle radiation transport code (MCNP), to calculate the X-ray fluorescence intensities and the detection limit for chromium in liquid samples. The experimental results agree with the results predicted by the simulation model, hence the model is used for optimization of the XRF system. Further, XRF mapping of chemical element distributions on a microscopic level has been obtained by using both X-ray scanning microscopy and full-field projection microscopy. The resultingdata from these microscopy measurements can guide further comprehensive environmental and industrial monitoring missions by providing additional spatial distribution information. In conclusion, the first research contribution presented in this thesis is the demonstration of the possibility to perform in-situ XRF measurements of chromium contamination in leachate with a limit of detection below the legal environmental limits. The second is the demonstration of XRF mapping on amicroscopy level, where a polycapillary X-ray optics setup achieves a similar intensity as a geometrically corresponding pinhole optics setup.

Vid tidpunkten för framläggningen av avhandlingen var följande delarbeten opublicerade: delarbete 2 (inskickat), delarbete 3 (accepterat), delarbete 4 (accepterat).

At the time of the defence the following papers were unpublished: paper 2 (submitted), paper 3 (accepted), paper 4 (accepted).

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Butler, Keith J. „The design of environmental test rigs“. Thesis, Aston University, 1986. http://publications.aston.ac.uk/11929/.

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Product reliability and its environmental performance have become critical elements within a product's specification and design. To obtain a high level of confidence in the reliability of the design it is customary to test the design under realistic conditions in a laboratory. The objective of the work is to examine the feasibility of designing mechanical test rigs which exhibit prescribed dynamical characteristics. The design is then attached to the rig and excitation is applied to the rig, which then transmits representative vibration levels into the product. The philosophical considerations made at the outset of the project are discussed as they form the basis for the resulting design methodologies. It is attempted to directly identify the parameters of a test rig from the spatial model derived during the system identification process. It is shown to be impossible to identify a feasible test rig design using this technique. A finite dimensional optimal design methodology is developed which identifies the parameters of a discrete spring/mass system which is dynamically similar to a point coordinate on a continuous structure. This design methodology is incorporated within another procedure which derives a structure comprising a continuous element and a discrete system. This methodology is used to obtain point coordinate similarity for two planes of motion, which is validated by experimental tests. A limitation of this approach is that it is impossible to achieve multi-coordinate similarity due to an interaction of the discrete system and the continuous element at points away from the coordinate of interest. During the work the importance of the continuous element is highlighted and a design methodology is developed for continuous structures. The design methodology is based upon distributed parameter optimal design techniques and allows an initial poor design estimate to be moved in a feasible direction towards an acceptable design solution. Cumulative damage theory is used to provide a quantitative method of assessing the quality of dynamic similarity. It is shown that the combination of modal analysis techniques and cumulative damage theory provides a feasible design synthesis methodology for representative test rigs.
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Chohan, Sukhvinder K. „Environmental degradation of polyethylene-based plastics“. Thesis, Aston University, 1996. http://publications.aston.ac.uk/9675/.

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The criteria involved in the degradation of polyethylene-based degradable polymer samples have been investigated, with a view to obtaining a clearer mechanism of photo-biodegradation. The compatibility of degradable polymer samples during materials recycling was also studied. Commercial and laboratory prepared degradable polymer samples were oxidised in different environments and the oxidation products formed were studied using various analytical chromatographic and spectroscopic techniques such as HPLC, FT-IR and NMR. It was found that commercial degradable polymer samples which are based on the ECO systems, degrade predominantly via the Norrish II process, whereas the other degradable systems studied (starch-filled polyethylene systems, transition metal systems, including metal carboxylate based polyethylene systems and the photoantioxidant-activator systems) photodegrade essentially via the Norrish I process. In all cases, the major photoxidation products extracted from the degradable polymer samples were found to be carboxylic acids, although, in the polymer itself a mixture of carbonyl containing products such as esters, lactones, ketones and aldehydes was observed. The study also found that the formation of these hydrophilic carbonyl products causes surface swelling of the polymer, thus making bioerosion possible. It was thus concluded that environmental degradation of LDPE is a two step process, the initiation stage being oxidation of the polymer which gives rise to bioassimilable products, which are consequently bioeroded in the second stage, (the biodegradation step). Recycling of the degradable polymer samples as 10% homogeneous and heterogeneous blends was carried out using a single screw extruder (180°C and 210°C) and an internal mixer (190°C). The study showed that commercial degradable polymer samples may be recycled with a minimal loss in their properties.
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Bajoria, Ankur. „Computational wind engineering using finite element package ADINA“. Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43891.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.
Includes bibliographical references (leaves 61-64).
Design of tall and long span structures is governed by the wind forces. Inadequate research in the field of wind dynamics has forced engineers to rely on design codes or wind tunnel tests for sufficient data. The present work uses a computational wind dynamics method to compare the coefficient of pressure (Cp) for the different aerodynamic shapes. ADINA, a finite element package, contains an inbuilt turbulence model which will be used to construct four different shapes for comparison. Results are verified with the experimental and simulation data. The effect of increase in the Reynolds number on the flow has been studied. Graphs for the pressure, velocity and turbulence energy distribution have been developed to assist the engineers in design.
by Ankur Bajoria.
M.Eng.
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Vedam, Padmanabha N. (Padmanabha Naranjan) 1977. „An Internet based multimedia infrastructure for collaborative engineering“. Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9011.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.
Includes bibliographical references (leaves 129-131).
The evolution of computer based collaborative environments has resulted in easier and more economical design efforts among geographically distributed design teams. Most of today's internet based collaborative applications allow people that are geographically dispersed to meet with each other using their computers and work together without actually having to travel. A prototype system was developed by taking two tactical planning applications and incorporating them into the collaboration model employed by CAIRO (Collaborative Agent Interaction control and synchROnization). This system was developed based on the collaboration infrastructure that was developed as a part of the Da-Vinci Society Initiative at MIT. The main focus of this research lies in the formalization of a multi-media based architecture that supplements the existing collaboration infrastructure. This architecture lays the groundwork for development of a robust collaboration system that incorporates audio/video conferencing, speech recognition and synthesis and three-dimensional virtual meeting environments in order to facilitate efficient collaboration.
by Padmanabha N. Vedam.
S.M.
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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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Bancroft, Wesley J. „Environmental response to burrowing seabird colonies : a study in ecosystem engineering“. University of Western Australia. School of Animal Biology, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0064.

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[Truncated abstract] Ecosystem engineers are organisms that physically modify habitat in a manner that modulate resource flows and species within ecosystems. Ecosystem engineering is distinct from classical interactions (competition, predation, parasitism and mutualism) in that it does not involve direct trophic exchange between organisms. The term ‘ecosystem engineer’ is a recently adopted one, and we are just beginning to investigate the occurrence and impact of engineers in ecosystems. My thesis explores the ecosystem engineering actions of Wedge-tailed Shearwaters, Puffinus pacificus, in a Mediterranean island, heathland ecosystem. I have approached this by (1) describing and quantifying the physical impact of these engineers, and (2) describing and quantifying the effects that these actions have on three major ecosystem components: the soil, the vascular plants, and the vertebrate fauna. Wedge-tailed Shearwaters are procellariid seabirds that excavate nesting burrows on offshore islands. The birds are colonial nesters, and on Rottnest Island, 17 km off the mainland coast of south-western Western Australia, their colonies have expanded considerably in recent decades. The expansion fits the trend observed in other tropicalorigin seabirds that breed in south-western Australia. In the last ten years, two new colonies have appeared (in a total of six) and the number of burrows on the island has almost doubled, to 11 745 ± 1320SE. In the same period the area occupied by the birds has increased by almost half ...
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Smith, Charles S. „Contracting for engineering and design services in the environmental restoration field“. Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26435.

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35

Reed, Kathaleen. „Skill sets required for environmental engineering and where they are learned“. Scholarly Commons, 2010. https://scholarlycommons.pacific.edu/uop_etds/2407.

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The purpose of this study was to investigate the knowledge, skills, abilities and traits environmental engineers need. Two questions were asked: what skills are considered important, and where are they learned? Dreyfus and Dreyfus' novice-to-expert model, which describes a progressive, five-step process of skill development that occurs over time on the job and through practical application, was used to frame this study. This study extended prior research by including data on professional skills and seeking the input of working professionals: in this case, the technical staff at the California Department of Toxic Substances Control. Quantitative methodology and descriptive statistics were used for data collection and analysis. Results showed that experienced professionals agree that professional or soft skills are essential are essential in the workplace Many technical skills are learned over time, through practice and meaningful application on the job that builds on principles learned through formal training. Professional skills are developed through a combination of formal training and experiential learning from work, or through life experiences. The implications for higher education are twofold. Environmental engineering programs would benefit by integrating professional skills development with existing curricula, and by giving students opportunities to develop experiential knowledge in the workplace. Results indicated that environmental engineering professionals with higher levels of education and more experience believed that science and mathematics were most appropriately learned in school, while engineering, skills in technology and other technical areas were best developed through a combination of formal education with experiential learning. The more experienced people also believed that life experiences, rather than work or school, were the best way to develop professional skills. These findings confirm the Dreyfus & Dreyfus model, which indicates that individuals move from novice to expert based on experience. Environmental engineers would benefit through continuing education and in-service training. Collaborative initiatives between higher education and practitioners in environmental engineering may prove mutually effective and beneficial to students, workers, educational institutions and employers.
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Watson, Mary K. „Assessment and improvement of sustainability education in civil and environmental engineering“. Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48981.

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Sustainable development through sustainable engineering is a promising strategy for combating unsustainable patterns of population growth, resource consumption, and environmental degradation. For sustainable engineering to alleviate global problems, however, improvements in undergraduate education are required to equip students with the knowledge and skills needed to engage in sustainable design. Consequently, the goal of this dissertation is to assess and improve sustainability education in civil and environmental engineering (CEE) at the Georgia Institute of Technology (Georgia Tech). Three phases of inquiry were conducted to (1) examine the current status of CEE sustainability education, (2) use assessment results to develop a pedagogically-innovative sustainability module, and (3) investigate the impacts of implementing the module into select CEE courses on student learning. Several key findings resulted from this work. First, the Sustainability Tool for Assessing Universities’ Curricula Holistically (STAUNCH®) suggested that integration of sustainability into the curriculum was incomplete and favored environmental sustainability. Second, CEE seniors’ conceptual understanding of sustainability, based on concept map results, was found to be generally correct, although limited in comprehensiveness, connectedness, and balance. Third, examination of capstone project reports (2002 and 2011) using the novel Sustainable Design Rubric revealed little change in the students’ sustainable design abilities over the past decade, due potentially in part to students simply “meeting the expectations” of project sponsors. Based on these insights, a five-part, learning-cycle-based sustainability module was developed and implemented in CEE capstone and cornerstone design courses. Higher learning gains for cornerstone students, as compared to seniors, supports future integration of the module into cornerstone design courses. While project results are especially important for CEE at Georgia Tech, other programs and institutions may benefit from the development and improvement of sustainability knowledge assessment tools, as well as the empirically-informed and theoretically-grounded sustainability module.
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Byrne, David Kevin. „Genetic and environmental perturbation effects on metabolic networks and engineering objectives“. Thesis, Boston University, 2012. https://hdl.handle.net/2144/12304.

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Thesis (Ph.D.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Phenotypic variation is produced through a complex web of interactions between genes and the environment and determines whether a trait has the ability to respond to natural or artificial selection. In metabolism, these concerted interactions define how energy is supplied and distributed throughout the cell. Since metabolic engineers seek to use cellular processes to improve the synthesis of valuable biochemical substances, there is great interest among scientists and engineers alike in determining the relative importance of genetic and environmental factors. To study the environmental and genetic effects on metabolic engineering applications, I use constraint-based metabolic modeling to develop a computational framework that systematically simulates and analyzes extracellular and intracellular perturbations on the metabolism of three microorganisms: Escherichia coli, Saccharomyces cerevisiae, and Shewanella oneidensis. Media compositions and gene- deletion strains are designed to optimize single or multiple engineering objectives, such as the maximization of production rate, yield and purity, or the minimization of the economic cost of raw materials. I use the framework to evaluate the production of several industrially important chemical commodities such as acetate, D-lactate, hydrogen, ethanol, formate, and succinate. By evaluating over 435 million simulated conditions and using 36 engineering metabolic traits, I classify the resultant phenotypes into 10-30 dominant meta-phenotypes for each organism. The meta-phenotypes illustrate global phenotypic variation and highlight organism-specific differences in biological and engineering capabilities. I show biological causality of high-performance engineering phenotypes and make available a web-based tool that was developed to permit public queries and visualization of optimal engineering designs and resultant metabolic pathway activities. Finally, I discuss relationships between engineering traits and phenotypes, trade-offs among multiple engineering objectives, and differences in phenotypic sensitivities that depend on perturbation type. Given the increasing number of sequenced genomes, model accuracy and available computing power, it is foreseeable that the developed framework can be extended to query a growing range of organisms, phenotypic variability, engineering applications and biological insights.
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Yeang, Chen-Hsiang 1969. „Implementation of a virtual environment system based on geographical information system and environmental models“. Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/40227.

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39

McIntosh, Dennis. „Reducing the environmental impact of aquaculture“. Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/289234.

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Aquaculture has great potential to help supply the nutritional needs of a growing population. To date, however, the benefits that aquaculture can have, have largely been overshadowed by the environmental degradation some segments of the industry have caused. The following body of work describes my efforts to help reduce the environmental impacts of aquaculture. By integrating aquaculture production into traditional agriculture, the impact of farming on already limited water resources and the reliance on chemical fertilizers can be reduced. Recent expansion of the aquaculture industry in Arizona has made it possible to study the integration of olive groves with marine shrimp culture. In chapter 3, I describe the characterization and evaluation of the effluent from an inland, low-salinity shrimp farm as a potential source of irrigation water. I found that 0.41 kg of ammonia-nitrogen, 0.698 kg of nitrite-nitrogen, 8.7 kg of nitrate-nitrogen and 0.93 kg of total phosphorus (TP) were made available as fertilizer each day in the effluent water. Based on the results of this first study, I decided to conduct a farm trial to quantify the effects of these shrimp farm effluents on olive trees. This work is described in chapter 4. Trees in all treatment groups grew an average of 40.1 cm over the four month study period. While growth of trees irrigated with shrimp farm effluent did not improve in respect to the other treatments, our results do indicate that irrigating with low-salinity water had no noticeable negative effects. Chapter 5 describes work conducted in Idaho, as part of a larger study aimed at reducing the effluent loads of phosphorus (P) from high density, flow-through aquaculture facilities. Research steps were taken to establish a relationship between TP and the carbon 12/13 isotope ratio (δ¹³C) and/or the nitrogen 14/15 isotope ratio (δ¹⁵N). Our findings suggest that both δ¹⁵N and δ¹³C are good better proxies for P, after correcting for P retention. A linear regression of %P (corrected) on δ¹³C and δ¹⁵N resulted in R2 values of 0.843 and 0.8622, respectively. This suggests that by tracking δ¹⁵N and/or δ¹³C through a high-density, flow-through aquaculture facility over time I will be able to determine the residence time of P with a high degree of accuracy.
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Baniszewski, Beth (Beth Ellen). „An environmental impact analysis of grinding“. Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32880.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references (leaves 39-40).
This thesis was intended to investigate the environmental impact of grinding in the United States manufacturing industry. Grinding is an ideal method for producing parts with a fine surface finish and high dimensional accuracy and for shaping hard or brittle workpieces. There are a wide variety of different types of grinding machines, each with different applications and slightly different energy requirements. Workpieces are generally flooded with a stream of coolant while being ground or placed in a spray of coolant mist. Coolant recycling systems are used to filter ground off chips out of coolant and to remove foreign oils and bacteria which pose health hazards. Oil mist collectors both clean mist coolant and prevent the toxic coolant from being inhaled by machinists. In total, 63 *10¹⁵ joules of energy are consumed per year by grinding in manufacturing, 57% of which is directly used in material removal. A total of 1.5*10¹⁰ pounds of scrap chips, spent grinding wheels, and used filters are produced each year as a result of grinding, over 99% of that being scrap chips. About 2.3 million gallons of fluids per year of grinding fluids are incinerated. Grinding creates a significant environmental footprint, creating a need for methods to reduce energy use in grinding and for ways to recycle solid waste that would otherwise be sent to landfills or incinerated.
by Beth Baniszewski.
S.B.
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41

Thiriez, Alexandre. „An environmental analysis of injection molding“. Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35646.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
Includes bibliographical references (p. 82-90).
This thesis investigates injection molding from an environmental standpoint, yielding a system-level environmental analysis of the process. There are three main objectives: analyze the energy consumption trends in injection molding machinery, explore the environmental performance of different technological alternatives, and provide a transparent life cycle inventory (LCI) identifying the mayor players in terms of environmental impact. The choice of injection molding machine type (hydraulic, hybrid or all-electric) has a substantial impact on the specific energy consumption (SEC), energy used per kg of processed polymer. The SEC values for hydraulic, hybrid and all-electric machines analyzed are 19.0, 13.2 and 12.6 MJ/kg respectively (including auxiliaries, compounding and the inefficiency of the electric grid). For hydraulic and hybrid machines SEC seems to exhibit a decreasing behavior with increasing throughput. This derives from spreading fixed energy costs over more kilograms of polymer as throughput increases. For all-electric machines SEC is constant with throughput. As viscosity and specific heat capacity increase so does SEC. Finally, SEC varies greatly with part shape. The thinner and the greater the projected area of the part the greater the SEC.
(cont.) When the polymer production stage is included in the analysis, the energy consumption values increase up to 100 MJ/kg. After polymer production, injection molding and extrusion have the greatest environmental impact in the whole LCI. The overall injection molding energy consumption (excluding polymer production) in the U.S. on a yearly basis amounts to 2.06 x 108 GJ. This value is of similar magnitude to the overall U.S. energy consumption for sand casting, and to the entire electricity production of some developed countries.
by Alexandre Thiriez.
S.M.
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Cho, Margaret H. (Margaret Hyunjoo) 1982. „Environmental constituents of Electrical Discharge Machining“. Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32827.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaves 30-31).
Electrical Discharge Machining (EDM) is a non-traditional process that uses no mechanical forces to machine metals. It is extremely useful in machining hard materials. With the advantages EDM has to offer and its presence as a common and useable technique, along with the other machining processes available to the industrial world, there is an added strain on the environment. The scope of this thesis includes analyzing the various inputs into EDM and the resulting outputs into the environment. A simplified model is used to analyze the process. The main categories of flow scrutinized in the model are material flow and energy flow. The most hazardous effect to the environment is found in the resin interaction of the wire EDM process where depending on the type of material machined, there is a potential presence of hazardous materials. There are efforts to recycle all salvageable materials such as wire and metal wastes, but currently no accountability system exists as manufacturers are responsible for their actions.
by Margaret H. Cho.
S.B.
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Kokkinen, E. (Eevi). „Measuring environmental awareness in the world“. Master's thesis, University of Oulu, 2013. http://urn.fi/URN:NBN:fi:oulu-201312142043.

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The aim of this study was to measure environmental awareness in the world. The level of environmental awareness of the nations is important, because previous literature and research on environmentalism have demonstrated that the publics’ support for the protection of the environment depends on the level of its environmental awareness. In order to improve environmental awareness it is essential to first understand the level of environmental awareness in the countries today. Furthermore, we studied what factors correlate with environmental awareness on national level. In addition to measuring environmental awareness in countries, we also measured the current state of the environment in those countries and if the environment was perceived to be deteriorating or improving. The main objective of this study was to form a profile of environmental awareness in the countries of the world. The purpose of this was to give a view on the level of the country in the three different elements of environmental awareness: motivation, knowledge and skills. We were also interested to know if our measurement of national environmental awareness correlated with other national level indicators of social and economic development. The theory, methodology and tools of our study originate from two earlier projects that measured environmental awareness in the Baltic Sea Region and in the states of India. For this study the research area is extended to cover the entire Earth. An online survey was used to acquire data about the three elements of environmental awareness: motivation to act pro-environmentally, level of education, and skills to act pro-environmentally. The questionnaire also asked five questions about other issues of interest: current state of the environment, trend of the environment, environmental knowledge, possibilities to act pro-environmentally, and availability of environmental information. A total of 1861 responses were received, and 543 of those passed the initial screening process. The respondents were experts in the field, and evaluated the situation in the neighbouring countries. In consequence, 57 countries obtained the sufficient number of answers. The survey proved to provide relevant and valid data. According to the results, the countries vary significantly in their performances in the eight indicators. Overall, the countries score better in motivation, skills, and availability of information than in state of environment, trend of environment, or environmental knowledge. It is worth noting that the median of six of the nine measures fell below 50, i.e. on the ‘not so good’ area. On the other hand, the three measures that had a median over 50 are measures of empowerment. Therefore, even if the environmental situation globally is seen as worse than it could or should be, the respondents overall feel that there are ways to improve it. In order to visualize the results, maps of them were created. They showed that environmental awareness in generally higher in Europe than elsewhere, although with some exceptions. It also seems that the countries near the Equator perform worse in environmental awareness, current state of the environment and trend of the environment. As for the tested correlations with other national level indicators, we found that environmental awareness is positively correlated with national wealth and the level of education. Furthermore, populations that hold postmaterialistic values were more likely to have higher environmental awareness than materialistic publics. All in all, the information about the country’s performance in the different elements of environmental awareness is expected to be helpful in national attempts to improve environmental awareness. In our view, the method we have presented in this work provides a ready-to-use survey for others to use to measure environmental awareness cross-nationally. Further runs of the survey would provide information on the development of environmental awareness in the world
Tämän tutkimuksen tarkoituksena oli mitata ympäristötietoisuutta maailmassa. Tieto ympäristötietoisuuden tasosta eri maissa on tärkeää, koska aikaisempi kirjallisuus ja tutkimus ovat osoittaneet, että kansalaisten tuki ympäristönsuojelulle riippuu yhteisön ympäristötietoisuuden tasosta. Parantaakseen ympäristötietoisuutta on tärkeää ensin tuntea ympäristötietoisuuden taso eri maissa tällä hetkellä. Itse ympäristötietoisuuden lisäksi olemme tutkineet sitä mitkä tekijät liittyvät ympäristötietoisuuteen kansallisella tasolla. Vielä lisäksi mittasimme ympäristön nykytilaa eri maissa ja sitä katsottiinko ympäristön tilan olevan heikentymässä vai paranemassa. Työn päätavoitteena oli selvittää millainen ympäristötietoisuuden profiili eri maissa on. Tarkoituksena oli siis luoda yleiskuva kolmen eri ympäristötietoisuuden ulottuvuuden (motivaatio, tiedot ja taidot) tasosta eri maissa. Selvitimme myös kuinka meidän mittaamamme ympäristötietoisuusindeksi korreloi muiden kansallisten, sosiaalista ja taloudellista kehitystä kuvaavien, indikaattoreiden kanssa. Käyttämämme teoria, menetelmät ja työkalut ovat peräisin kahdesta aikaisemmin toteutetusta hankkeesta, joissa mitattiin ympäristötietoisuutta Itämeren alueen maissa ja Intian osavaltioissa. Tähän selvitykseen tutkimusalue on laajennettu kattamaan koko Maa. Tutkimuksen data saatiin online-kyselyn kautta. Kyselyssä vastaajia pyydettiin arvioimaan kahdeksaa ympäristötietoisuuteen liittyvää osa-aluetta: ympäristön nykytilaa, ympäristön tilan trendiä, maan koulutuksen tasoa, kansalaisten tietoa ympäristöstä, heidän motivaatiota toimia ympäristömyönteisesti, heidän taitoja toimia ympäristömyönteisesti, heidän mahdollisuuksia toimia ympäristömyönteisesti, ja ympäristöä koskevan tiedon saatavuutta. Yhteensä vastauksia saatiin 1861 ja 543 näistä läpäisi alustavan seulonnan. Vastaajat ovat alan asiantuntijoita, jotka arvioivat naapurimaiden tilannetta. Kysely tuotti riittävän määrän maakohtaista dataa 57 maan arvioimiseen. Tulostemme mukaan eri maat suoriutuvat huomattavan vaihtelevasti arvioimillamme kahdeksalla osa-alueella. Yleisesti maailmassa kansalaisten motivaatio ja taidot, ja ympäristöön liittyvän tiedon saatavuus arvioitiin olevan paremmalla tasolla kuin ympäristön tilan, trendin tai kansalaisten ympäristötuntemuksen. Huomattavaa on, että kuudessa osa-alueessa yhdeksästä vastausten mediaani jäi alle 50:n eli "ei niin hyvä" -alueelle. Toisaalta ne kolme osa-aluetta, joissa mediaani oli yli 50, koskevat mahdollisuuksia muuttaa tilannetta. Näin ollen, vaikka maailmanlaajuisesti ympäristön tilan nähdään olevan huonompi kuin se voisi tai pitäisi olla, vastaajat ovat sitä mieltä, että on olemassa keinoja sen parantamiseksi. Visualisoidaksemme tuloksia esitimme ne myös karttoina. Kartat osoittivat, että ympäristötietoisuus on yleisesti suurempi Euroopassa kuin muualla maailmassa joitakin poikkeuksia lukuun ottamatta. Näyttää myös siltä, että maat lähellä päiväntasaajaa suoriutuvat keskimääräistä huonommin niin ympäristötietoisuudessa kuin nykyisessä ympäristön tilassa ja ympäristön trendissä. Korrelaatiot muiden kansallisen tason indikaattoreiden kanssa osoittivat, että ympäristötietoisuus korreloi positiivisesti kansallisen varallisuuden ja koulutuksen tason kanssa. Lisäksi tulokset tukivat mm. oletusta siitä, että ympäristötietoisuus on korkeampi postmaterialistissa yhteisöissä kuin materialistisissa. Kaiken kaikkiaan tiedosta eri maiden suoriutumisesta ympäristötietoisuuden eri osa-alueilla on oletettavasti hyötyä yrityksissä parantaa ympäristötietoisuuden tasoa maailmassa. Mielestämme tässä työssä esittämämme menetelmä tarjoaa käyttövalmiin kyselyn ympäristötietoisuuden mittaamiseen kansainvälisesti. Toistamalla kysely sopivin väliajoin saataisiin tietoa ympäristötietoisuuden kehittymisestä maailmassa
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44

Li, Zhuo. „ARDUINO BASED ENVIRONMENTAL AIR MONITORING SYSTEM“. Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1499093616376284.

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45

Buerk, Phillip C. „ENVIRONMENTAL INTERNSHIP STORE PLANNING, ARCHITECTURE, CONSTRUCTION, AND ENGINEERING DEPARTMENT FEDERATED DEPARTMENT STORES“. Miami University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=miami1070655104.

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46

Risemark, Eriksson Martin. „Environmental stress of electrical machine winding insulation“. Thesis, Uppsala universitet, Elektricitetslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326711.

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The conducting winding of an electrical machine is insulated in order to prevent any short circuits to occur within the machine. This insulation is during its lifetime exposed to several environmental stresses and therefore plays an important role in the life length of the machine. Accelerated stress tests are used to investigate what design and material is most suitable for a good endurance of a product. In this master thesis, new accelerated test methods for the insulation system in an electrical machine are developed and evaluated. The study resulted in four stress tests that simulate the thermal stress, the thermomechanical stress and the ambient stress from direct oil cooling. Three diagnosis tests and a material analysis were used in order to evaluate how these accelerated stress test methods affected the insulation. The diagnosis tests showed no clear sign of deterioration of the insulation in terms of change in electrical characteristics. However, the material analysis indicated deterioration of the insulation, such as cracks and oxidation of the material. These changes show that the test methods are capable to affect the insulation, but will need more time to cause a breakdown, since a stator of this kind is expected to have a very long life length. Therefore, in future work on this topic, these test methods should continue for a longer time and it would likely be interesting to look into other diagnosis tests.
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47

Baresel, Christian. „Environmental management of water systems under uncertainty“. Doctoral thesis, Stockholm : Mark- och vattenteknik, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4396.

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Foroughi, Abdol Rahim. „Uncertainties in environmental loading on offshore structures“. Thesis, University of Sunderland, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385010.

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49

Ithurburn, Bertrand F. „Weighting environmental impacts in software distribution systems“. Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10144826.

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Requirements engineers who try to design sustainable systems may have to compromise when it comes to different environmental impacts. For example, compact fluorescent lamps contain mercury, a dangerous material. But these lamps also save energy. They reduce consumption at the expense of introducing toxic substances into the environment. To deal with these trade-offs, researchers have developed weighting metrics to account for every type of impact in a single assessment. However, the weights have the potential to direct the system design toward neglecting lowly weighted environmental concerns.

This study aims to clarify the effects of different weighting configurations. The project employs a mixing triangle that weights three different areas of environmental impact against each other. It then compares the effects of an application service provider to the effects of a system that uses locally hosted software. The comparison uses multiple weighting configurations.

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Popovicova, Jarmila 1968. „Transport of gas-phase contaminants in the unsaturated zone“. Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282136.

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The goal of this dissertation was to examine transport of gas-phase contaminants and the processes causing nonideal transport. With one exception, all experimental work was performed with synthetic porous media (glass beads). I performed experiments with methane, trichloroethene, benzene, and toluene. Transport experiments for gas-phase contaminants in dry homogeneous and heterogeneous porous media were performed to study dispersion of gases during transport. Axial diffusion was found to be a primary contributor to dispersion at gas velocities < 20 cm min⁻¹. Conversely, mechanical mixing was the main contributor to total dispersion at gas velocities > 50 cm min⁻¹. Dispersion of gas-phase contaminants during transport through dry heterogeneous (macroporous) medium was caused by three processes: axial diffusion, which was predominant at gas velocity < 20 cm min⁻¹ and negligible at gas velocity > 100 cm min⁻¹; mechanical mixing, predominant at gas velocities ranging from 30 to 120 cm min⁻¹; and diffusion between macropore and micropore domains, the main contribution to total dispersion at gas velocities above 160 cm min⁻¹. The latter process was responsible for rate-limited transport of gas-phase contaminants (methane, trichloroethene, benzene) through heterogeneous porous medium causing increased dispersion, early breakthrough, and tailing of breakthrough curves. Transport of gas-phase contaminants through the unsaturated heterogeneous porous medium showed a similar trends. The presence of heterogeneity and immobile water caused nonequilibrium transport of methane and trichloroethene. Predictions of breakthrough curves, which fit the experimental data well, were estimated independently and demonstrated that diffusion between macropore and micropore domains have a more pronounced effect on transport nonequilibrium than diffusion in immobile water. Retention of gas-phase contaminants in the unsaturated porous media was also examined. Solid-phase sorption of gas-phase contaminants was minimal and thus not responsible for delay during the transport. The major contribution to total retention was due to accumulation at the gas-water interface. For example, 62-73% and 30-50% total trichloroethene mass was retained at the interface during transport through the glass beads and aquifer material, respectively. Accumulation of benzene at the interface contributed to total benzene retention by 53-61% of total mass.
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