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Dissertations / Theses on the topic 'Water safety'

Author: Grafiati
Published: 4 June 2021
Last updated: 19 February 2023

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1

Hylin, Frida Douglass. "Drinking Water Safety in African Countries." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produktutvikling og materialer, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18508.

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The following report is the result of a literature study of published documents presenting the current water supply situation in Sub-Saharan Africa, in combination with a field trip to the Mpagne village in Cameroon. The objective of the project has been to study and discuss the current theoretical approach on sustainable water supply, as well as to generate possible technical solutions and present administrative changes required. A thorough background analysis demonstrates the need for improvement on a local village level as well as on a regional, national and international level. Key findings are high failure rates as a consequence of the absence of evaluation of past projects, as well as the fact that many agencies do not work in line with existing policies and theoretically developed approaches to solve the problem. Further, there is a general need to cultivate local political will for long-term commitment and funding of the sector. Although some of the organizations engaged in the sector have started to realise that there is a need for an alteration of approach angle, thus far there is little evidence of the change required to move towards universal coverage. A needs assessment and a requirement specification were developed based on the findings in the background analysis. This was then used to generate possible technical solutions to be further studied. In the process of deciding upon technical solutions, the information gathered in the village, especially that related to the previously implemented system, has been important. After analysing the data collected in Mpagne and studying available technology the following alternatives were developed: Alternative 1: Groundwater exploitation with flywheel handpump, elevated storage tank and gravity based distribution to community tap standAlternative 2: Rainwater harvesting with swale-trench filtration and flywheel handpump, elevated storage tank and gravity based distribution to community tap standAlternative 3: Combination of groundwater exploitation and rainwater harvesting, similar to alternative 1, with the addition of RWH at the village school. In order to systematically compare these options and decide upon a best suited solution, the indicator comparison methodology developed during the fall project was used in combination with a SWOT-analysis of each concept. The final results obtained indicate that alternative 3 was slightly better than the other two alternatives. A description of the technology required for the new water supply facility in Mpagne was then presented to the level it is possible with the information available at this stage. The intention is for this to serve as an initial suggestion to be presented to the villagers for further discussion. The report continues with a discussion of an implementation strategy with an enhanced focus on how the technical system can be installed in Mpagne in a social, economic and environmentally sound context. The discussion covers the following four phases: 1.Planning2.Construction3.Operation and maintenance4.Follow-up and evaluation This process will be especially important considering the past failed project in Mpagne, and an agency should give special attention to including the villagers in all levels from an early stage. This to avoid the deficiency between the solution implemented and the actual needs resulting from the past project. Further findings are the current situation of downgrading external factors such as the availability and reliability of spare part supply networks as well as lack of general technical support. This is a primary cause of project failure today. The lack of coordination amongst the sector operators, including NGO’s, donor agencies, and local and international government entities, is also an important factor which slows down the progress of developing an efficient and effective water supply sector. Lastly, until internal village level factors as well as external regional and national aspects are adequately satisfied, the agencies operating in the rural water supply sector today have a great responsibility in terms of creating an enabling environment for sector development. Project conduction should be done in adherence with existing policies until the local governments and/or private partners have succeeded in developing an institutional framework to support a well-functioning water supply sector.
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2

Pam, Eugene Dung. "Risk-based framework for ballast water safety management." Thesis, Liverpool John Moores University, 2010. http://researchonline.ljmu.ac.uk/5986/.

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Ballast water has been identified as a major vector for the translocation of Non- Indigenous Invasive Species (NIS) and pathogens across zoogeographical regions and subsequent discharged into recipient port states/regions. This is bound to increase given factors like the globalization of trade and the economy of scale of the ship size. Established NIS has posed significant threat to the human health, economy, finances and marine bio-diversity of recipient regions and port states. The risks associated with the discharged NIS are uncertain and difficult to assess due to the stochastic nature of species assemblages and dispersal mechanism. The safest control measure advocated by the IMO is the conduct of ballast water exchange at sea while appropriate and effective proto-type treatment technologies are being developed and approved for future application. This study has been conducted while recognizing the inability of probabilistic approaches applied in ballast water risk management to addressing uncertainty and inadequacy of data. A qualitative approach using powerful multi-criteria decision making techniques and the safety principles of the Formal Safety Assessment framework have been utilized in this research to develop three generic models for ballast water hazard estimation, risk evaluation and decision-making analysis respectively. The models are capable of being modified and utilized in the industry to address the problems of uncertainty and inadequacy of data in ballast water management. This is particularly useful as an interim measure for port states in developing economies (with insufficient data and technology) to developed robust ballast water management plans. While recognising the huge impact of ballast water pollution in recipient regions this study recommends that ballast water management programmes be given due recognition as an important element of sustainable development programmes at national and international levels. The non-availability of a benchmark based on previous research on which to fully validate the research outcome was identified as a major limitation of this research study. The models developed will therefore be subject to modifications as new data become available.
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Rich, Kyle. "Bridging Troubled Waters: Examining Culture in the Canadian Red Cross' Swimming and Water Safety Program." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24278.

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The Canadian Red Cross (CRC) offers its Swimming and Water Safety Program throughout Canada. The program is delivered by over 35 000 active instructors to over one million participants every year. The research in this thesis is part of a collaborative, interdisciplinary project in partnership with the CRC that examined ways to improve programming for cultural and ethnic minority populations. The thesis is written in the stand alone paper format. The first paper evaluates the program’s content, through a critical whiteness lens, to identify obstacles to offering effective programming to people of diverse cultural and ethnic backgrounds. Based on these findings, I created and piloted a cultural safety training module for program instructors. The second paper then evaluates the effectiveness of this training module to provide recommendations for the CRC to optimize its management of diversity within its organization and aquatics facilities across the country. Collectively, this thesis bridges both understandings of Eurocanadian and whiteness discourses as well as critical whiteness and organizational theories to more holistically understand processes of inclusion, exclusion, accommodation, and the management of diversity in the context of a nation-wide Canadian sport and recreation program.
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4

Kilanko-Oluwasanya, Grace Olutope. "Better safe than sorry : towards appropriate water safety plans for urban self supply systems." Thesis, Cranfield University, 2009. http://dspace.lib.cranfield.ac.uk/handle/1826/4453.

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Self Supply Systems (SSS) can be defined as privately owned household level water sources. The research focus is on urban self supply hand dug wells in Abeokuta, Nigeria. Self supply wells serve an estimated 45% of Abeokuta’s population. SSS can be gradually upgraded to improve water quality, but water quality can also be improved through effective risk management. The World Health Organization (WHO) has developed a risk management tool known as Water Safety Plans (WSP), but the tool has not been tried for SSS. This research focuses on the relevance of the generic WHO water safety plans tool to SSS, with the aim to develop an appropriate water safety framework for self supply sources to ensure acceptable household water. Water from self supply wells is used for both ingestion and non-ingestion household activities. The water quality of the sources is poor and not safe for consumption with faecal coliform counts in excess of 100 cfu/100 ml of water. Self supply wells in Abeokuta are plagued by four main water safety threats; style of source operation – primarily through bucket and rope -, construction problems, proximity to sources of contamination, and user’s hygiene practices. Users are in denial of the health consequences of unsafe water. There is a predominantly reactive attitude to water safety management. The main source management approaches include access and hygiene management. To appropriate existing WSP to SSS, source and water safety control measures require user acceptability to be sustainable in terms of adoption and compliance. Incentives are needed for the adoption of SSS water safety plans. A two- phase supporting program is necessary: awareness and enlightenment campaigns and relevant training activities. Water safety development for self supply wells need to be initiated and coordinated by an established institution other than the source owners. This research suggests the Department of Public Health as the institution to facilitate the development of water safety plans for SSS in Abeokuta, Nigeria.
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5

Orru, Kati. "Europeanising risk regulation : drinking water safety in Estonia and Lithuania." Thesis, King's College London (University of London), 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580327.

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6

Lee, Youho. "Safety of light water reactor fuel with silicon carbide cladding." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/86866.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 303-314).
Structural aspects of the performance of light water reactor (LWR) fuel rod with triplex silicon carbide (SiC) cladding - an emerging option to replace the zirconium alloy cladding - are assessed. Its behavior under accident conditions is examined with an integrated approach of experiments, modeling, and simulation. High temperature (1100°C~1500°C) steam oxidation experiments demonstrated that the oxidation of monolithic SiC is about three orders of magnitude slower than that of zirconium alloys, and with a weaker impact on mechanical strength. This, along with the presence of the environmental barrier coating around the load carrying intermediate layer of SiC fiber composite, diminishes the importance of oxidation for cladding failure mechanisms. Thermal shock experiments showed strength retention for both [alpha]-SiC and [beta]-SiC, as well as A1₂O₃ samples quenched from temperatures up to 1260°C in saturated water. The initial heat transfer upon the solid - fluid contact in the quenching transient is found to be a controlling factor in the potential for brittle fracture. This implies that SiC would not fail by thermal shock induced fracture during the reflood phase of a loss of coolant accident, which includes fuel-cladding quenching by emergency coolant at saturation conditions. A thermo-mechanical model for stress distribution and Weibull statistical fracture of laminated SiC cladding during normal and accident conditions is developed. It is coupled to fuel rod performance code FRAPCON-3.4 (modified here for SiC) and RELAP-5 (to determine coolant conditions). It is concluded that a PWR fuel rod with SiC cladding can extend the fuel residence time in the core, while keeping the internal pressure level within the safety assurance limit during steady-state and loss of coolant accidents. Peak burnup of 93 MWD/kgU (10% central void in fuel pellets) at 74 months of in-core residence time is found achievable with conventional PWR fuel rod design, but with an extended plenum length (70 cm). An easier to manufacture, 30% larger SiC cladding thickness requires an improved thermal conductivity of the composite layer to reduce thermal stress levels under steady-state operation to avoid failure at the same burnup. A larger Weibull modulus of the SiC cladding improves chances of avoiding brittle failure.
by Youho Lee.
Ph. D.
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7

Cheng, Zhiyuan S. M. Massachusetts Institute of Technology. "Safety analysis of a compact integral small light water reactor." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127303.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 110-112).
Small modular reactors (SMRs) hold great promise in meeting a diverse market while reducing the risk of delays during nuclear construction compared to large gigawatt-sized reactors. However, due to lack of economy of scale, their capital cost needs to be reduced. Increasing the compactness or power density of the nuclear island is one way to reduce capital cost. This work first assesses the transient analysis of a compact integral small light water reactor to examine its safety performance. Subsequently, a parametric optimization study with the goal of increasing its power density (i.e. improve its market competitiveness) while maintaining safety is performed. A model of the reactor is established using RELAP5/3.3gl, with reference to the features of Nuward SMR. Nuward is a compact 170 MWe Pressurized Water Reactor, whose key features include the use of Compact Steam Generators and a large water tank in which the containment submerges for passive heat removal.
A transient analysis of the reference reactor after Loss of Flow Accident, Station Blackout, and Loss of Coolant Accident is carried out. Following all three accidents, the integrity of the fuel and the reactor is maintained. The passive cooling system is estimated to provide 12 - 13 days of grace period. The parametric optimization study indicates that the size of the tank can be reduced to half and still maintain sufficient margin to both short-term and long-term safety goals after all three transients with an estimated grace period of 7 - 8 days. In addition, the configuration of the passive safety system can be rearranged to reduce the size of the containment to 76% of the reference design without affecting its safety performance. By increasing the coolant enthalpy change, which also results in a higher thermal efficiency, the electrical output of the reference design can be enhanced by 44% without major design changes.
If the number of pumps in the vessel are increased by 2, the electrical output can be enhanced by 102% while satisfying all safety criteria. The uprated power that satisfies a 72-hour grace period requires a tank size that is 32.5% of the reference design. Such compact and simplified nuclear steam supply system can partially address the lack of economy of scale for the reference SMR and improve its market competitiveness.
by Zhiyuan Cheng.
S.M.
S.M. Massachusetts Institute of Technology, Department of Nuclear Science and Engineering
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8

Guillermo, Díez Fernández. "Safety aspects of Cermic Fully Encapsulated fuel for Light Water Reactors." Thesis, KTH, Fysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101992.

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9

Perez, Huertas Daniel. "Cyber-Security and Safety Analysis of Interconnected Water Tank Control Systems." Thesis, KTH, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-55972.

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Over the last few years, wireless sensor networks have become an interesting tool for controlling processes. Their use in this field has significantly increased based on recent technological advances which permit higher computational power, smaller size and lower cost. This makes them very suitable for integration in large networks of hundreds of interconnected motes that work together being spread in huge areas. However, the wireless nature of these systems make them susceptible to remote attacks, for example by hackers. That is, the wireless devices can be externally manipulated to disturb the correct behavior of the process. In some critical facilities, such as, power plants, hospitals, factories using dangerous materials it is very important to ensure the resiliency and safety of the control system even if a hacker takes full control of some wireless nodes.
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10

Summerill, Corinna. "Improved water safety planning : insights into the role of organisational culture." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/5443.

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Unsafe water, as many recent outbreaks have shown, has the potential to cause widespread illness and even death. Water Safety Plans (WSPs) are advocated as the best way of ensuring good safe drinking water using a risk management approach. Using a case study approach to generate qualitative data, organisational culture and WSP development in water suppliers of varying size, development and structure was studied to look for examples of best practice or barriers to effective implementation. Despite WSPs being promoted since 2004, suppliers are still experiencing challenges in implementation, with deeper organisational culture barriers prevalent such as: lack of awareness and recognition; uncertainty; complacency; poor internal relationships; competing priorities; and contrasting internal cultures, in addition to the commonly espoused reasons of a lack of time or resources. Concern was raised that the public health motivator of WSPs was becoming lost, as a wide range of additional ‘added value’ drivers and benefits were identified such as cost savings or commercial drivers. This was echoed in broader organisational missions and drivers identified; whilst may employees still identified quality and public health as important, more formal declarations often prioritised other areas. In response to identified organisational culture barriers, a ‘taxonomy’ of positive cultural attributes and a number of practical tools were developed that may assist suppliers in developing a supportive organisational culture for sustainable WSP implementation. These positive elements included: managerial commitment; learning culture; effective internal and external relationships; accountability; open reporting culture; continual improvement culture; empowerment of staff; organisational commitment; proactivity; leadership and advocacy; mindfulness of public health; image and competitiveness. A number of recommendations can be made to those wishing to implement WSPs. Primarily, it is urged that organisational culture and how it can impact on effective WSP implementation should be considered. Perceived lack of time and resources may actually be representative of deeper cultural barriers, and recognise that WSP implementation is more than just following a set of instructions, it will require instilling a water safety ‘culture’ within the organisation.
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11

Omar, Yahya Yussuf. "Risk management for drinking water supplies in developing countries : the influence of culture on water safety plans." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8564.

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Consumption of unsafe water in developing countries results in considerable number of illnesses and deaths annually. The World Health Organization and the International Water Association are promoting the use of water safety plans (WSPs), a risk management approach aimed at attaining water safety. This study investigated how culture impacts on the implementation of WSPs in these countries. Combining interpretive and critical paradigms resulted in the choice of qualitative methodologies utilizing multiple-case studies. Cases from India, Uganda, and Jamaica are each embedded with three units of analysis: promoters of WSPs, water utilities and their customers. Thematic analysis of data generated from semi-structured interviews, field observations and documents revealed eleven cultural factors impacting on the implementation of WSPs. Analyses of these factors led to various groupings and the subsequent development of a taxonomy categorizing these factors as being either enabling, limiting, or neutral in relation to WSPs. Findings show all the limiting factors to be deviations from the values and principles on which they are built. The findings have also led to the development of a culturally adapted risk management framework. This four-step cyclical & iterative framework is designed to address the impact of culture on the implementation of WSPs. The implementation of WSPs will take time and will require continuous improvement to the process. The successful management of drinking water risks in developing countries will require a broad institutional approach and a concerted effort that involves institutions beyond the water utilities. As such, targeted recommendations are first made towards achievement of good governance. Activities that will lead to the embracement of WSP by stakeholders along with suggestions to attain its institutionalization are also put forward. Recommendations towards addressing negative cultural factors include suggestions on dealing with: pollution causing rituals, bettering storage related practices, addressing excessive water use in rituals, counteracting belief that water should be free, fighting corruption and improving compliance, changing deliver-first safety-later attitude, and improving knowledge management practices.
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12

Ijabadeniyi, Oluwatosin Ademola. "Effect of irrigation water quality on the microbiological safety of fresh vegetables." Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/25555.

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Irrigation water is perhaps the leading pre-harvest source of contamination of fresh vegetables in the world. In this thesis, the effect of source water from the Olifants River and the Wilge River on the bacterial quality of water in the Loskop Canal that they feed and also the subsequent contribution to the bacterial contamination of fresh vegetables was determined for a period of twelve months. Also effect of attachment time on the survival of Listeria monocytogenes and the effect of chlorine on L. monocytogenes attached to vegetables were determined. Finally, a step-wise logistic regression analysis was made to determine whether various predictor variables could be used to predict the occurrence of L. monocytogenes, Salmonella spp and intestinal Enterococcus in irrigation water and vegetables (i.e., cauliflower and broccoli). COD and turbidity were higher in the Olifants River and the Wilge River than in the Loskop Canal that they feed, according to the water guidelines set by the World Health Organisation (WHO) and the Republic of South Africa (RSA). The level of the COD and turbidity were significantly different in terms of the two rivers in comparison with the canal. Levels of faecal coliforms and Escherichia coli were also higher than the WHO standard. Staphyloccocus aureus, intestinal Enterococcus, Salmonella, L. monocytogenes were recovered from the two rivers and the canal. Apart from L. monocytogenes that was not recovered from cauliflower, all bacterial pathogens recovered from the surface water were recovered from the vegetables. This study also indicated that L. monocytogenes could attach to both surface and subsurface structures of both tomatoes and spinach within 30 min, and that even after 72 h, it still remained viable. It also indicated that chlorine treatment is more effective against surface L. monocytogenes compared with subsurface inoculated L. monocytogenes. Finally, the logistic regression analysis of the sampled data showed that COD was statistically reliable to indicate a high probability of L. monocytogenes, turbidity reliable to indicate a high probability of intestinal Enterococcus and faecal coliforms and coliforms reliable to indicate a high probability of Salmonella in irrigation water. Low aerobic colony count (ACC) was statistically significant for the prediction of the three pathogens on vegetables.
Thesis (PhD)--University of Pretoria, 2011.
Food Science
unrestricted
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13

Mowrey, James A. "Control system modeling for a boiling water reactor." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/17083.

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14

Raqué, Manuel [Verfasser]. "Safety Analysis for a Fuel Qualification Test with Supercritical Water / Manuel Raqué." Karlsruhe : KIT Scientific Publishing, 2015. http://www.ksp.kit.edu.

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15

Tucker, Marilyse. "Teaching Water Safety Skills to Children with Autism Using Behavioral Skills Training." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc955103/.

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Behavioral skills training (BST) and in situ training (IST) have been evaluated as methods to teach different safety skills to individuals with developmental disabilities. Research on BST has examined topics such as gun safety, abduction prevention, poison avoidance, and sexual abuse prevention. A large safety issue that is missing from the literature is drowning prevention and water safety skills. Drowning is one of the most prevalent issues facing facing children with Autism Spectrum Disorder (ASD), particularly those who elope from their homes or caregivers. The current study aimed the effectiveness of using BST+IST to teach three water safety skills to three children with ASD. The intial form of intervention was BST with total task presentation of the skill, using verbal instruction, modeling, rehearsal, and feedback. If this intervention did not result in an increase in performance, the skill was broken down into individual component presentation, in which each component of the skill was taught using the same procedures. Results from the current study showed that BST+IST was effective in teaching all skills to all participants.
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16

Primavera, Francesca. "Water Safety Plan and Fault Tree Analysis for the management and risk assessment of a drinking water supply system." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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This work of thesis studies the approach of the Water Safety Plan, that is applied to a part of the drinking water supply network managed by AIMAG S.p.A. The Water Safety Plans have been introduced by the World Health Organization and have been identified as the most effective way to systematically guarantee the safety of the drinking water system, the quality of the water supplied, and the protection of the health of consumers. Through a preventive and qualitative analysis that includes risk assessment and management, the Water Safety Plans make it possible to guarantee over time the absence of potential physical, biological, and chemical hazards in the water available for consumption. The result obtained through the application of the Water Safety Plan involves the construction of a risk matrix, that allows the development of an improvement plan for the control of each hazard and associated risk (in priority scale). After that, the previously performed analysis is supported through the application of statistical and probabilistic techniques used in the reliability analysis to optimize the control activities based on a risk assessment. The first one is the Fault Tree Analysis, which is a deductive technique supported by Boolean algebra that focuses on a particular undesirable event and provides a method for identifying possible causes. In parallel with the application of the Fault Tree Analysis, the Monte Carlo method is applied, which is a computational method based on random sampling of certain variables to obtain numerical results. Finally, the result obtained through the application of both methodologies is the definition of the probability of failure of some nodes and internodes that are part of a portion of the drinking water supply network managed by AIMAG S.p.A. At the end, the work of thesis lead to results which prove that the qualitative approach of the Water Safety Plans can be effective, especially if supported by different types of analysis.
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17

Mattick, Karen. "The survival of Salmonella spp. at high temperature and low water activity." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341195.

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18

Nadig, Ragava. "Development of environmental health and safety database for small communities." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2113.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains viii, 95 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 69-70).
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19

Eul, Ryan C. "The impact of passive safety systems on desirability of advanced light water reactors." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/41267.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2006.
Includes bibliographical references (leaves 121-123).
This work investigates whether the advanced light water reactor designs with passive safety systems are more desirable than advanced reactor designs with active safety systems from the point of view of uncertainty in the performance of safety systems as well as the economic implications of the passive safety systems. Two advanced pressurized water reactors and two advanced boiling water reactors, one representing passive reactors and the other active reactors for each type of coolant, are compared in terms of operation and responses to accidents as reported by the vendors. Considering a simplified decay heat removal system that utilizes an isolation condenser for decay heat removal, the uncertainty in the main parameters affecting the system performance upon a reactor isolation accident is characterized when the system is to rely on natural convection and when it is to rely on a pump to remove the core heat. It is found that the passive system is less certain in its performance if the pump of the active system is tested at least once every five months. In addition, a cost model is used to evaluate the economic differences and benefits between the active and passive reactors. It is found that while the passive systems could have the benefit of fewer components to inspect and maintain during operation, they do suffer from a larger uncertainty about the time that would be required for their licensing due to more limited data on the reliability of their operation. Finally, a survey among nuclear energy experts with a variety of affiliations was conducted to determine the current professional attitude towards these two competing nuclear design options. The results of the survey show that reactors with passive safety systems are more desirable among the surveyed expert groups. The perceived advantages of passive systems are an increase in plant safety with a decrease in cost.
by Ryan C. Eul.
S.M.
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20

Howard, Guy. "Effective approaches to water supply surveillance in urban areas of developing countries." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/1032/.

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21

Nichita, Eleodor Marian. "A heterogeneous finite element method and a leakage corrected homogenization technique." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17655.

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22

Swanton, Kerry Vivienne. "Food safety and waste water reuse : heavy metal contamination in peri-urban Varanasi, India." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428327.

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23

Widger, Ian Roy. "Improvements of high pressure water sprays used for coal dust extraction in mine safety." Thesis, University of Manchester, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386033.

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24

Pinho, Jorge. "Experimental investigation of cavitation in a safety relief valve using water: extension to cryogenic fluids." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209095.

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This thesis addresses the experimental investigation of the cavitation phenomenon and its main consequences on the normal operation of a safety relief valve (SRV). More particularly, limitation of the mass flux discharged and alteration of the hydraulic fluid forces behavior is of main interest for the proper design and sizing of such devices. In nuclear or thermal engineering systems, the use of SRVs is mandatory since it represents the ultimate protection device before an accident occurs, caused by a sudden pressurization of the system. A careful design and sizing of the SRV is therefore essential. The complete understanding of the physics taking place in the flow through the valve is required to guaranty and optimize the security of the protected process.

In order to investigate the above effects of cavitation in a SRV, two different orifice sized valves (API 2J3 type and a transparent model based on an API 1 1/2G3 type) are tested in two different experimental facilities expressly built for this purpose. Instead of using a spring, the design of both valves allows the adjustment of the disc at any desired lift. Hence the static behavior of the valves is investigated. Both facilities, operating at different magnitude scales, allow the study of single phase and cavitating flow conditions required to properly determine the most important hydraulic characteristics, and access on any potential scaling effect between both sized SRVs. Experimental techniques used for the determination of the hydraulic characteristics include temperature, flow rate, fluid forces and pressure measurements both upstream and downstream the test sections.

Results show a similar influence of cavitation on the flow characteristics of both valves, minimizing any potential scaling effect. The liquid pressure recovery factor FL, which is normally used to identify a choked flow condition in a control valve, is experimentally determined for the first time in a SRV. The existence of a local minimum located at small openings of the lift indicates a change on the flow characteristics of both valves, which is related to the location of the minimum cross section of the flow that does not remain constant for every lift position. An extended experimental campaign is performed to analyse the effect of the blowdown ring adjustment located around the nozzle of the API 2J3 valve. Results confirm that the position of the ring has an important contribution for the hydraulic forces acting on the valve disc.

In the second part of the research, precise optical diagnostic techniques are successfully applied in the transparent valve to locally characterize the flow topology in a SRV experiencing cavitation. These results are innovative and enrich the experimental database available in the literature for the characterization and understanding of the flow physics in such devices. In a first configuration, high speed visualization is applied to observe qualitatively the flow pattern and the inception of liquid vaporization. Particle tracking results suggest that vapor bubbles are formed in the core of vortices detached from the shear layers attached to the valve. These rotational structures promote lower pressure regions allowing the liquid to vaporize. In the second configuration, particle image velocimetry is applied to extract the velocity field in both single phase and cavitating flow conditions. Results of PIV confirm the existence of a submerged jet just downstream the minimum section. This jet is characterized by two non-symmetric shear layers at its sides. Under cavitation conditions, PIV results confirm that vapor bubbles are formed preferentially inside the jet shear layers. The phenomenon of mass flux limitation caused by cavitation is reproduced at small openings of the valve and interaction with the flow topology is highlighted. It is observed that limitation of the flow occurs when the vena contracta is shifted towards the minimum geometrical section of the flow. Finally, instabilities of the flow downstream the critical section are investigated in the frequency domain by means of time resolved data. Results suggest that vortex shedding mechanism is dominated by a constant Strouhal number which is slightly affected by the valve opening.

In the last part of the research, the methodology used in water is extended and applied to cryogenic liquids. Two different geometries are investigated experimentally and numerically using water and liquid nitrogen as working fluids. Results suggest that both the flow coefficient (determined at single flow conditions), and the liquid recovery factor (used to identify choked flows), are independent on the fluid properties and therefore, an hydraulic similarity relation can be proposed.

This research project was carried out at the von Karman Institute for Fluid Dynamics (VKI), in Belgium, in close collaboration and with the funding of Centre Technique des Industries Mécaniques (CETIM) in France.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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25

Calvillo, Anthony. "Evaluation of Water-only Decontamination for Firefighters’ Turnout Gear." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1530880114309489.

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26

Atay, Itri. "Water Resources Management in Greece : Perceptions about Water Problems in the Nafplion Area." Thesis, Stockholms universitet, Kulturgeografiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-85379.

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27

Dolcini, Carlotta. "Valutazione e gestione del rischio nelle filiere idro-potabili secondo il modello dei Water Safety Plan." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.

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Il Water Safety Plan (WSP) è un metodo che permette di effettuare una valutazione dei rischi presenti in un sistema idro-potabile, dalla captazione dell’acqua al punto di consegna all’utilizzatore finale. Qui possono esserci rischi che vanno a ridurre la qualità dell’acqua distribuita, in termini di parametri chimico-fisici, o a creare problemi nella sua erogazione e, una volta identificati, il WSP permette di gestirli attraverso misure di controllo o eventuali azioni di miglioramento. Sviluppare un Water Safety Plan è un’attività molto impegnativa e onerosa, ma comporta numerosi vantaggi. In particolare, permette di ottenere un miglioramento nella gestione del sistema idro-potabile, aumentando la garanzia di qualità del prodotto distribuito e la sicurezza per il consumatore finale. Inoltre, rappresenta uno strumento di supporto nella decisione e nella programmazione strategica degli investimenti da fare nel sistema idrico. Nell’elaborato verranno descritte le fasi che compongono lo sviluppo del WSP per un determinato sistema idrico. Queste sono principalmente: identificazione dei pericoli e degli eventi pericolosi (tramite check-lists); valutazione del rischio di ogni evento pericoloso attraverso matrici di rischio; individuazione delle misure di controllo in atto nel sistema e conseguente rivalutazione del rischio; identificazione di azioni di miglioramento da implementare per ridurre i rischi elevati a un livello accettabile. Si tratta di un processo iterativo, nel quale la ricerca del risultato di ciascuna fase può richiedere una modifica di quanto definito nella fase precedente. In seguito, verranno riportati due esempi applicativi di sviluppo di WSP, realizzati nel corso di un tirocinio presso NIER Ingegneria, per due specifici sistemi acquedottistici. Infine, questi verranno analizzati e confrontati, mettendo in risalto i problemi incontrati nella loro redazione e possibili elementi di sviluppo futuro.
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28

Mohd, Thiyahuddin Mohd Izzat. "Experimental and numerical characteristics of portable water-filled road safety barrier system under different impact conditions." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/71458/1/Mohd%20Izzat_Mohd%20Thiyahuddin_Thesis.pdf.

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This research has developed an innovative road safety barrier system that will enhance roadside safety. In doing so, the research developed new knowledge in the field of road crash mitigation for high speed vehicle impact involving plastic road safety barriers. This road safety barrier system has the required feature to redirecting an errant vehicle with limited lateral displacement. Research was carried out using dynamic computer simulation technique support by experimental testing. Future road safety barrier designers may use the information in this research as a design guideline to improve the performance and redirectional capability of the road safety barrier system. This will lead to better safety conditions on the roadways and potentially save lives.
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29

Masri, Hassan Mohamed. "Evaluating post-harvest practices on the quality and safety of Kona coffee." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/89217.

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Coffee grown in the United States represents less than 1% of the world's supply, and most of it comes from the state of Hawai'i. Kona coffee, grown on the western side of the island of Hawai'i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai'i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (31.6 4.3%), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.
Doctor of Philosophy
Coffee grown in the United States represents less than 1% of the world’s supply, and most of it comes from the state of Hawai’i. Kona coffee, grown on the western side of the island of Hawai’i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw*). (*Water activity is the measurement of water vapor pressure generated by the free or non-chemically bound water in foods and other products. Water activity (range of 0 to 1) is an important indicator for the shelf life of foods and the occurrence and growth of microorganisms). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai’i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (27 to 36 %), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.
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30

BJÄRKBY, SARAH, and FRIDA VÄRNLUND. "Ensuring Safety and Security in the Era of Digital Water : A qualitative study on the implications following the digital transformation of the Swedish water industry." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299627.

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As water systems are critical infrastructures, their continuous service is essential for maintaining vital functions of society. During the past decades, a number of severe global challenges have put increasing pressure on the water systems, threatening the quality and availability of water. Digitalization is expected to play a fundamental role in managing these challenges, making the digital transformation of the water industry an imperative rather than a choice for water utility providers. However, the implementation of digital solutions also entails a number of challenges, risks and vulnerabilities to water systems. As such, water utility providers are faced with increased complexity and uncertainty, where the safety and security of the system is at stake. This thesis addresses the potential implications of a digital transformation of the water industry by exploring how digitalization affects the Swedish water sector from a safety and security perspective. By doing so, the thesis aims to enhance the understanding of how Swedish water utility providers can manage its ongoing digital transformation. The thesis consists of a qualitative research study where interviews with 16 representatives from the Swedish water industry contributed with a broad perception of the implications of the digital transformation. Theory on high reliability organizations and resilience was applied to obtain a deeper understanding of what the potential safety and security implications may entail for Swedish water utilities in managing and reaping the benefits of their digital transformation. The study finds that representatives from the Swedish water sector mainly view benefits related to the efficiency of their operations from their ongoing digital transformation, while the mentioned drawbacks are generally related to their organizational abilities in managing the emerging risks and increased level of complexity. With increasing digitalization, Swedish water utilities coincide with the high reliability organization theory to a higher extent, which emphasizes the increasing importance of employing bothtechnical reliability and organizational resilience practices. This thesis concludes that technical reliability has historically been well-managed and prioritized by utilities, whilst organizational resilience has become an increasingly important aspect to focus on with increasing digitalization. Hence, practices of organizational resilience, such as incorporating clear strategies, integrating work between divisions and increasing follow-up from disturbances, should be employed on a wider scale among water utilities.
Då vattensystem är kritisk infrastruktur är deras kontinuerliga funktion avgörande för att upprätthålla vitala funktioner i samhället. Under de senaste decennierna har ett antal allvarliga globala utmaningar ökat trycket på vattensystemen, vilket hotar vattnets kvalitet och tillgänglighet. Digitalisering anses vara avgörande för att hantera dessa utmaningar, vilket gör digitalisering av vattenindustrin till en nödvändighet snarare än ett val för VA-bolag. Att implementera digitala lösningar medför emellertid också ett antal utmaningar, risker och sårbarheter för vattensystem. VA-bolagen står således inför en ökad komplexitet och osäkerhet där systemsäkerheten står på spel. Denna uppsats behandlar de potentiella implikationer som kan uppstå av en digital transformation av vattenindustrin genom att undersöka hur digitalisering påverkar den svenska VA-sektorn ur ett säkerhetsperspektiv. Genom detta syftar uppsatsen till att öka förståelsen för hur svenska VA-bolag kan hantera sin pågående digitalisering. En kvalitativ forskningsstudie har genomförts där intervjuer med 16 representanter från den svenska VA-sektorn bidrog med en bred uppfattning om digitaliseringens implikationer för den svenska VA-sektorn. Teori om high reliability organizations och resiliens användes för att fördjupa förståelsen för vad de potentiella säkerhetsimplikationerna kan innebära för svenska VAbolag, både för hantering av riskerna och för att ta till vara på fördelarna med den digitala transformationen. Studien visar att representanter från den svenska VA-sektorn, i deras pågående digitalisering, huvudsakligen ser fördelar relaterade till effektiviteten i vattenproduktionen, medan de nämnda nackdelarna i allmänhet är relaterade till deras egna förmågor att hantera de framväxande riskerna och den ökade komplexiteten. Med ökad digitalisering kan svenska VA-bolag i högre utsträckning beskrivas med teori kring high reliability organizations, vilket medför en ökad vikt av att arbeta med både teknisk tillförlitlighet och organisatorisk resiliens. Teknisk tillförlitlighet har historiskt hanterats väl och prioriterats av VA-bolag, medan organisatorisk resiliens har blivit allt viktigare att fokusera på med ökad digitalisering. Därför drar denna uppsats slutsatsen att arbete med organisatorisk resiliens, såsom att införa tydliga strategier, integrera arbetet mellan avdelningar och öka uppföljningsarbetet efter störningar, bör utföras i större skala bland VA-bolag.
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31

Godoy, Neto Bento de. "Segurança hídrica na bacia hidrográfica do Ribeirão Pirapetinga, Caldas Novas – Goiás – Brasil." Ilha Solteira, 2018. http://hdl.handle.net/11449/157436.

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Orientador: Cláudio Antônio Di Mauro
Resumo: A abordagem sobre a segurança hídrica diz respeito ao conhecimento dos aspectos ambientais da bacia hidrográfica, os usos atuais e tendências dos recursos naturais, considerando a multiplicidade de usos da água. Consiste em considerar tanto o planejamento do uso e ocupação da terra, quanto dos recursos hídricos na sua integridade ambiental e social, e não somente de um ponto de vista econômico, visando à segurança hídrica no abastecimento de água para a população local. Assim, neste trabalho propõe-se contribuir para a segurança hídrica do abastecimento público da população urbana de Caldas Novas, Goiás, Brasil. Nos procedimentos metodológicos, por meio de revisão bibliográfica pertinente e levantamentos de campo na bacia hidrográfica do Ribeirão Pirapetinga, especialmente dos aspectos ambientais e socioeconômicos impactantes na segurança hídrica municipal, realizou-se levantamento de dados relativos à história de Caldas Novas, ocupação territorial, ocorrência das águas termais, crescimento populacional, expansão da área urbana, caracterização da bacia hidrográfica quanto a aspectos de solo, clima, geomorfologia, uso do solo e ocupação da terra (entre 1995 e 2017), disponibilidade hídrica e vazão consumida pelos principais setores usuários da bacia hidrográfica: a irrigação e o abastecimento público. Dentre os resultados destacam-se a constatação da vulnerabilidade do atual sistema em atender à demanda de água na cidade, para a qual as ações de preservação de água tratada têm... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The water safety approach refers to understanding the environmental aspects of the hydrographic basin, as well as current and trend uses of natural resources, considering the plurality of uses. It means taking into account planning of land use and occupancy, as well as planning of water resources on their environmental and social entirety, and not only from an economic point of view, thus aiming the improvement of local population life quality. The proposition of this work is contributing to the water safety of urban population public supply in Caldas Novas, Goiás, Brazil. Through a relevant bibliographic review and field surveys in the Pirapetinga Stream Basin, especially regarding environmental and socioeconomic aspects impacting on local water safety, data were collected on the history of Caldas Novas, its territorial occupation, occurrence of thermal waters, population growth, expansion of the urban area, characterization of the hydrographic basin regarding aspects of soil, climate, geomorphology, land use and land occupancy (between 1995 and 2017), as well as water availability and water flow rate consumed by the main users of the basin: irrigation and public supply. One verified the current system vulnerability in meeting the city demand for water, to which the actions of reserving treated water have only a palliative effect, against the increasing demand. One observed the high susceptibility to drought occurrence due to direct catchment without accumulation. A situatio... (Complete abstract click electronic access below)
Mestre
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32

Fridolf, Tina. "Dam safety in a hydrological perspective-Case study of the historical water system of Sala Silver Mine." Licentiate thesis, KTH, Land and Water Resources Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1780.

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The old water system in Sala, formerly belonging to thesilver mine, is analysed with regard to dam safety focusing onthe hydrological aspects. The hydrological safety of the riskclass I dams in the area, built in the 16th century, is notconsidered adequate according to the Swedish guidelines fordesign flood determination. A review is made of internationalprinciples for design flood determination. The overview showsthat there is no common principle used internationally whendealing with design flood for dams. In some countries there isan ambition to implement risk assessment for evaluation ofhydrological safety. However, at present Australia is the onlycountry that has fully integrated risk assessment in theirdesign flood guidelines. A risk assessment of the water systemin Sala shows that neither increasing the spillway capacity norimplementing flood mitigation measures in the watershed haveany significant effect on dam safety in the area. Nothingindicates that watersheds with a high presence of mires, likein the Sala case, should be particularly well suited forimplementing flood mitigation in the watershed as a dam safetymeasure. In order to safely handle the design flood in Sala andavoid dam failure due to overtopping the flood needs to bediverted from the water system.

Key words:dam safety; design flood; flood mitigation;hydrological; risk assessment

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33

Givan, Ethan. "Selection of Pathogen Surrogates and Fresh Produce Safety: Implications for Public Health and Irrigation Water Quality Policy." TopSCHOLAR®, 2015. http://digitalcommons.wku.edu/theses/1545.

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Foodborne illness continues to be a substantial public health issue in the United States, with fresh produce being one of the leading causes of outbreaks. Understanding routes of contamination of fresh produce and how pathogens survive on plant surfaces is paramount in improving food safety and reducing risk to public health. The objectives of this study were to select environmental E.coli isolates as pathogen surrogates of Salmonella typhimurium and E.coli O157:H7, assess lettuce plant contamination by spray irrigation water, and evaluate a common industry quality control (QC) E.coli strain (ATCC 25922). Selections of E.coli surrogates were made utilizing biofilm and leaf attachment data from lab scale assays. Five surrogates were found to be similar in biofilm formation and leaf attachment capabilities of the pathogens, while the common QC strain was significantly different than Salmonella in both biofilm formation and leaf attachment (p < 0.05). Persistence of surrogates, pathogens and the QC strain on lettuce plants was assessed in greenhouse scale experiments, where it was found that all isolates were above detection levels for 22 days. Die-off rates were calculated for all isolates, with the QC strain having the greatest rate of die-off in the first experiment (k = -4.52) and the second greatest in the second experiment (-2.82) while the pathogens and selected surrogates had statistically similar and lower rates of die-off. Based on this information, current policies concerning the sampling and management of irrigation waters and crops for microbial safety may be insufficient. It is recommended that sampling methods and frequencies be adjusted for irrigation waters and fresh produce, and the use of projected die-off rates not be used for the determination of time intervals needed before a crop is safe to harvest.
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34

McGladdery, Candice. "Evaluation of irrigation water quality guidelines for arsenic and lead, with implications for food and feed safety." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/77846.

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As mining and industry continue to impact agricultural lands and waterways, and as competition for access to fresh water increases, the agricultural industry must adapt to grow crops in increasingly polluted lands using ever more contaminated water sources. As a result, the likelihood that crops grown under such conditions could pose a food safety risk is set to rise. This research assesses the extent to which potentially hazardous trace elements, As and Pb, present in irrigation water at concentrations deemed acceptable by the Irrigation Water Quality Guidelines, impact the food (and feed) safety of crops. Four crops are investigated under two glasshouse trials. The first assesses foliar absorption of As and Pb under irrigation to the aboveground biomass and the second assesses root uptake of As and Pb via the effects of medium- to long-term irrigation programs. Results indicate that under such trace element loaded conditions, some crop parts exceed food (or feed) safety thresholds, with concentrations ranging from 0.01 mg.kg-1 to 33.38 mg.kg-1 As, and 0.01 mg.kg-1 to 62.41 mg.kg-1 Pb, on a dry mass basis. Leafy vegetables present the highest food safety risk. Therefore, if international food safety standards for fresh produce are to be adhered to, the Irrigation Water Quality Guidelines for As and Pb should be critically reviewed so as to negate all possible future contamination of fresh produce as a result of irrigation inputs. A food (and feed) safety consequence matrix is proposed as a means of modelling the effect of irrigating according to the Irrigation Water Quality Guidelines on food (and feed) safety.
Dissertation (MSc)--University of Pretoria, 2019.
Plant Production and Soil Science
MSc
Unrestricted
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35

Mahafha, Musiiwa Morris. "Food safety risks associated with the use of contaminated agricultural water in the production of table grapes." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/53512.

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Most agricultural water sources are often considered contaminated, due to poorly maintained sanitation systems, polluted river streams and other water catchment areas. Agricultural water used for irrigation and reconstitution of pesticides is suspected to play a direct or indirect role in the transmission of human pathogens to fresh produce. The contamination of fresh table grapes during pesticide spraying can therefore be seen as a potential risk factor. This study focuses on identifying possible sources and levels of bacterial contamination in a river, holding dam and tank in table grape production areas. In addition, the ability of selected pathogens to attach and survive on table grape surfaces was studied using transmission electron microscopy. Water sources sampled in this study were found to be microbiologically contaminated. Microbial populations varied with season, sampling period within a season and water treatment conditions. No human pathogens were detected under natural field conditions on crops irrigated with contaminated water used for reconstituting agricultural pesticides. This study further showed a wide range of pesticide products that permitted survival and multiplication of most of the tested foodborne pathogens i.e. Escherichia coli 157:H7, Listeria monocytogenes, Salmonella enterica subsp. enterica serovar Typhimurium and Staphylococcus aureus. This information provides insight into the potential risk that may be associated with table grapes due to the use of contaminated water. These findings highlight the importance of considering pesticides used, water quality and spray schedules prior to application. Detailed risk assessment studies on the potential of contaminated irrigation water and the actual link with foodborne disease outbreaks have not been investigated and should in future be determined as well as intervention strategies.
Mini Dissertation (MSc)--University of Pretoria, 2012.
Microbiology and Plant Pathology
MSc
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36

TimÃteo, SÃsthenis de Lima. "Guidelines struture of water safety Plan for extreme events : droughts and floods. Case study company of the situation room omplementation of Management Water Resources of CearÃ." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13686.

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A Water Safety Plan for Extreme Events - PSAEE, has the purpose of description the procedures in potentially critical situations due to the occurrence of extreme weather events (droughts and floods). Provides the developing of preventive actions and contingency plan as a way to mitigate the effects of these phenomena. Will be developed in different and complementary steps, aiming anticipation, recognition and risk assessment, identification and monitoring of vulnerable regions and the implementation of a warning network against Floods and Droughts. The present document describes guidelines for structuring a Water Safety Plan for Extreme Events, Floods and Droughts, structured in five (05) steps; 1. Preliminary Steps, 2 Diagnostic System; 3 Operational Monitoring; 4. Management Plans and 5.Validation and Verification. As a case study, the document analyzed the process of implementing the Situation Room of the Water Resources Management Company of Cearà - COGERH , also presenting some suggestion of a Work Plan for the Situation Room, which will serve as a Management Center of Extreme Hydrological Events for the State of CearÃ, Brazil.
Um Plano de SeguranÃa de Ãgua para Eventos Extremos â PSAEE, tem como objetivo a descriÃÃo de procedimentos em situaÃÃes potencialmente criticas devido a ocorrÃncia de eventos climÃticos extremos (Secas e Cheias). Prevà o desenvolvendo de aÃÃes preventivas e plano de contingÃncia como forma de mitigar os efeitos destes fenÃmenos. Serà desenvolvido em etapas distintas e complementares, visando a antecipaÃÃo, reconhecimento e avaliaÃÃo de riscos, a identificaÃÃo e monitoramento de regiÃes vulnerÃveis, a implementaÃÃo de rede de alerta contra Cheias e Secas. O presente trabalho descreve diretrizes para estruturaÃÃo de um Plano de SeguranÃa de Ãgua para Eventos Extremos, Cheias e Secas, estruturado em 05 (cinco) etapas; 1. Etapas Preliminares, 2. DiagnÃstico do Sistema; 3. Monitoramento Operacional; 4. Planos de GestÃo e 5. ValidaÃÃo e VerificaÃÃo. Como estudo de caso, o trabalho analisou o processo de implantaÃÃo da Sala de SituaÃÃo da Companhia de GestÃo dos Recursos HÃdricos do Cearà â COGERH, apresentando, tambÃm, sugestÃo de um Plano de Trabalho para a Sala de SituaÃÃo, a qual servirà de Centro de GestÃo de Eventos Extremos HidrolÃgicos para o Estado do CearÃ, Brasil.
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37

Gerla, Stephanie Rae. "Emergency Preparedness in Utah Households with Emphasis on Water and Food Storage Conditions." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3934.

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Emergency preparedness steps taken by individuals in Utah households were evaluated in 3 studies. Study 1 evaluated the 2011 landline and cell phone Behavioral Risk Factor Surveillance System Survey and General Preparedness Optional Module results from two states, Louisiana and Utah, to find factors from demographic and medical data that can be used to predict emergency preparedness in individuals. Stepwise logistical regression analysis ascertained the ability of chosen variables to predict individuals' preparedness. The rate of prepared individuals was lower if they were between the ages of 18 to 54 years, when compared to the reference age group of 65 or older. Also, the rate of prepared participants was lower if they were female, had children under age 18 at home, or were unable to afford a doctor in the past year. Rate of prepared respondents was higher if they owned a home or were married (p <0.05). Study 2 evaluated water stored for emergency purposes in households throughout Utah for coliform, E. coli, free chlorine, and antimony. Ninety one percent of the stored water samples were found to be safe for human consumption. However, 9% of water samples were not considered safe due to over chlorination or the presence of coliform. Of 240 samples, 7 contained coliform and 14 samples had total chlorine levels over the Environmental Protection Agency's 4 ppm limit. Water in clear, polyethylene terephthalate soda bottles, even when stored for >18 months, did not exceed 0.3 ppb antimony, a level significantly lower than the Environmental Protection Agency limit of 6.0 ppb antimony. Study 3 measured for one year the temperature and humidity of food storage areas in 67 households within Utah. In 63% of locations, temperatures exceeded 24 °C, which can be considered abusive for food storage. The maximum temperature reached in a food storage area was 37.9 °C. Percent relative humidity exceeded 60% in 43% of food storage areas, which can be considered abusive for food stored in packaging permeable to moisture. The maximum percent relative humidity reached was 92.5%. In conclusion, most water stored for emergency purposes was considered safe, but temperature and humidity conditions for most food storage areas exceeded recommended maximums, and emergency preparedness of households within Utah needs to be improved.
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38

Tshivhandekano, Itani. "Water quality in the City of Tshwane, South Africa and its role in food safety for vegetable production." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-07092008-151025.

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39

Suprayogo, Didik. "Testing the safety-net hypothesis in hedgerow intercropping : water balance and mineral N leaching in the humid tropics." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326060.

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40

Samhan, Farag A. "Coliphages as indicators and test organisms for assessment of hygienic safety of water, wastewater and liquid organic wastes." Beuren Stuttgart Grauer, 2005. http://d-nb.info/989873919/04.

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41

Keirle, Robert Scott. "The relevance of catchment management to Drinking Water Safety Plans within the UK, with particular emphasis on Wales." Thesis, Swansea University, 2009. https://cronfa.swan.ac.uk/Record/cronfa43046.

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My research related to an in-depth investigation of catchment management in the context of Drinking Water Safety Plans, the principal aims of which were to: 1) Establish to what extent catchment management had been implemented in England and Wales, in both historic and current contexts; 2) Identify the roles, remits and activities of the key stakeholders in catchment management in England and Wales; 3) The extent to which climate change could affect future catchment management; and 4) Determine the ability of catchment management to facilitate Drinking Water Safety Planning in Wales, and to identify any scope for possible improvement. The requisite literature review was necessarily exhaustive and resource-intensive, and encompassed the following subject headings: • Water resources; • Water quality; • Climate change; • Catchment management; • Public water supplies; • Private water supplies; • Stakeholder engagement; • Regulatory (at the European, national and devolved levels) and management models; and • Governance issues. As the catchment is at the top of the drinking water supply chain, if we address water quality and quantity problems there, the result is a cleaner, cheaper, more secure product for the consumer. Consequently, I decided to develop an Abstraction Safety Index - along with an associated catchment environmental assessment methodology - for determining the overall environmental quality of water within a catchment, and for expressing this quantitatively. This mathematical index has been subject to peerreview by water companies and other environmental stakeholders. The index was calibrated using a range of different types of catchments - used for both private water supply and public water supply purposes - and it was subsequently used to consider a number of alternative conceptual scenarios, to determine how changes to regulatory, legal and institutional models could feasibly affect the environmental quality of catchments in Wales, in order to improve the quality of abstracted water.
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42

Khamis, Ibrahim Ahmad. "Simulation of nuclear power plant pressurizers with application to an inherently safe reactor." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184378.

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Pressurizer modeling for predicting the dynamic pressure of the PIUS system is presented. The transient behavior of this model for the PIUS system was investigated. The validity of this model for the PIUS system is limited to transients that are neither too large nor too long in duration. For example, the model is not capable of describing events following a complete loss of liquid for the pressurizer. However, the model can be used for qualitative prediction of the PIUS system behavior for a wide variety of severe transients. A review of pressurizer modeling indicates that the neglecting of the change in the internal energy of the subcooled water during transients is an acceptable assumption. The inherently safe feature of the PIUS system was confirmed through the self-shutdown of the reactor or, in some cases, through reactor power reduction as a result of the ingress of the pool boric acid solution into the primary system. This dynamic model was constructed of three major components: (1) The primary loop, (2) The secondary loop, and (3) The natural convection loop through the pool. A lumped parameter model, uniform heat transfer, and point kinetics have been the main approximations in this model. Other approximations are mentioned during the modeling of each component of the model. The dynamic model was simulated using the DARE-P continuous system simulation language which was developed in the Electrical Engineering Department at the University of Arizona.
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43

Strömner, Lisa. "Vattenkvalitet och risker vid ändrat intag för vattenförsörjning i Västerås." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-151566.

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Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant. The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality. In this Master’s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared. Existing water quality data were compared, and pollution risks were investigated in two ways. Firstly potential risks in the catchment area were identified through compiling previously reported information and map analysis. Secondly, possible accident scenarios from shipping were identified. Following this, SMHI simulated the accident scenarios and their estimated effects on the two sites were then assessed.   This research shows that the water quality difference between sites is small but key differences exist in the levels of organic matter, color, transparency and temperature, making the Granfjärden location preferable. Potential problems associated with the low oxygen levels found during the end of summer at Granfjärden may be addressed by temporarily raising the intake point. It should be noted however that this temporary solution may increase the exposure to pollution. In conclusion, accident scenario simulations showed the potential concentration of pollutants at both sites is low, with effluents diluted at least 1000 times. Prevailing southwesterly and westerly winds occuring at both intake points generate a clockwise circulation in Västeråsfjärden.  This causes all effluents from urban activities to reach that intake point, which is the most notable risk associated with this site.  In contrast, the two largest risks for the Granfjärden site are shipping effluents and the microbiological load from individual sewage treatment systems and animal waste.
Vatten är vårt viktigaste livsmedel och en förutsättning för allt liv. I de fall där råvatten för beredning av dricksvatten tas från ytvatten är det ytterst viktigt att säkerställa en bra vattenkvalitet, lämpat för dricksvattenberedning. Västerås stad tar idag sitt råvatten från Västeråsfjärden, i Mälarens västra delar, 3 km från Västerås stad. I staden finns bl.a. småbåtshamnar, oljehamn, avloppsreningsverk, Svartåns utlopp, nödbräddavlopp, avloppspumpstationer och dagvattenutsläpp. Dessa aktiviteter påverkar vattenkvaliteten i fjärden negativt och därför har Mälarenergi AB valt att undersöka möjligheterna att flytta intaget till Granfjärden, 10 km öster om Västeråsfjärden. Där skulle råvattenintaget inte vara lika utsatt för samhällets direkt negativa vattenpåverkan. Intaget kan läggas på ett större djup och där kan vattenkvaliteten vara bättre och mindre riskutsatt. I detta examensarbete har vattenkvaliteten och föroreningsriskerna jämförts mellan fjärdarna. Analysresultat från provtagningar i Granfjärden jämfördes med prover från Västeråsfjärden. Riskerna behandlades i två delar. I den första delen identifierades föroreningsrisker genom att sammanställa material från tidigare projekt samt genom att studera kartor. I den andra delen togs olycksscenarion inom sjöfarten fram. SMHI simulerade dessa scenarion och en bedömning gjordes sedan över hur riskutsatta de båda råvattenintagen är. Trots det stora avståndet från Västerås stad till Granfjärden var skillnaden i vattenkvalitet mellan fjärdarna förvånansvärt liten, men skillnader påvisades för några av de analyserade parametrarna. Granfjärdens bottenvatten hade signifikant lägre halter organiskt material, lägre färgtal och lägre temperatur än det nuvarande råvattenintaget. Däremot förekom lägre syrgashalter i slutet av sommaren än vid råvattenintaget i Västeråsfjärden. Om problem skulle uppstå i dricksvattenberedningen till följd av låga syrgashalter finns möjlighet att byta till ett grundare intag vid samma punkt. Det grundare intaget är dock mer utsatt för risker än det djupare. Samtliga utsläpp från de simulerade olyckorna späddes ut minst 1000 gånger innan de spred sig till råvattenintagen. Båda råvattenintagen är som mest utsatta vid sydvästlig och västlig vind. I Västeråsfjärden ger dessa vindriktningar en medurs strömningsbild i fjärden, vilket innebär att föroreningsutsläpp från staden förs mot råvattenintaget. De största riskerna för råvattenintaget i Granfjärden är utsläpp i farleden och den mikrobiologiska belastningen från enskilda avlopp och djurhållning. I Västeråsfjärden är den största riskfaktorn utsläpp från stadens aktiviteter och verksamheter längs den östra stranden.
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44

Jasiulevicius, Audrius. "Analysis methodology for RBMK-1500 core safety and investigations on corium coolabiblty during a LWR sever accidnet." Doctoral thesis, KTH, Energy Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3703.

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This thesis presents the work involving two broad aspectswithin the field of nuclear reactor analysis and safety. Theseare: - development of a fully independent reactor dynamics andsafety analysis methodology of the RBMK-1500 core transientaccidents and - experiments on the enhancement of coolabilityof a particulate bed or a melt pool due to heat removal throughthe control rod guide tubes.

The first part of the thesis focuses on the development ofthe RBMK-1500 analysis methodology based on the CORETRAN codepackage. The second part investigates the issue of coolabilityduring severe accidents in LWR type reactors: the coolabilityof debris bed and melt pool for in- vessel and ex-vesselconditions.

The safety of the RBMK type reactors became an importantarea of research after the Chernobyl accident. Since 1989,efforts to adopt Western codes for the RBMK analysis and safetyassessment are being made. The first chapters of this Thesisdescribe the development of an independent neutron dynamics andsafety analysis methodology for the RBMK-1500 core transientsand accidents. This methodology is based on the codes HELIOSand CORETRAN. The RBMK-1500 neutron cross section library wasgenerated with the HELIOS code. The ARROTTA part of theCORETRAN code performs three dimensional neutron dynamicsanalysis and the VIPRE-02 part of the CORETRAN package performsthe rod bundle thermal hydraulics analysis. The VIPRE-02 codewas supplemented with additional CHF correlations, used inRBMK-type reactor calcula tions. The validation, verificationand assessment of the CORETRAN code model for RBMK-1500 wereperformed and are described in the thesis.

The second part of the thesis describes the in- vesselparticulate debris bed and melt pool coolabilityinvestigations. The role of the control rod guide tubes (CRGTs)in enhancing the coolability during a postulated severeaccident in a BWR was investigated experimentally. Thisinvestigation is directed towards the accident managementscheme of retaining the core melt within the BWR lowerhead.

The particulate debris bed coolability was also investigatedduring the ex-vessel severe accident situation, having a flowof non-condensable gases through the porous debris bed.Experimental investigations on the dependence of the quenchingtime on the non-condensable gas flow rate were carriedout.

The first chapter briefly presents the status ofdevelopments in both the RBMK- 1500 core analysis and thecorium coolability areas.

The second chapter describes the generation of the RBMK-1500neutron cross section data library with the HELIOS code. Thecross section library was developed for the whole range of thereactor conditions (i.e. for both cold and hot reactor states).The results of the benchmarking with the WIMS-D4 code andvalidation against the RBMK Critical Facility experiments isalso presented here. The HELIOS generated neutron cross sectiondata library provides a close agreement with the WIMS-D4 coderesults. The validation against the data from the CriticalExperiments shows that the HELIOS generated neutron crosssection library provides excellent predictions for thecriticality, axial and radial power distribution, control rodreactivity worths and coolant reactivity effects, etc. Thereactivity effects of voiding for the system, fuel assembly andadditional absorber channel are underpredicted in thecalculations using the HELIOS code generated neutron crosssections. The underprediction, however, is much less than thatobtained when the WIMS-D4 code generated cross sections areemployed.

The third chapter describes the work, performed towards theaccurate prediction, assessment and validation of the CHF andpost-CHF heat transfer for the RBMK- 1500 reactor fuelassemblies employing the VIPRE-02 code. This chapter describesthe experiments, which were used for validating the CHFcorrelations, appropriate for the RBMK-1500 type reactors.These correlations after validation were added to the standardversion of the VIPRE-02 code. The VIPRE-02 calculations werebenchmarked against the RELAP5/MOD3.3 code. It was found thatthese user-coded additional CHF correlations developed for theRBMK type reactors (Osmachkin, RRC KI and Khabenskicorrelations) and implemented into the code by the author,provide a good prediction of the CHF occurrence at the RBMKreactor nominal pressure range (at about 7 MPa). Transition andfilm boiling are also predicted well with the VIPRE-02 code forthis pressure range. It was found, that for the RBMK- 1500reactor applications, EPRI CHF correlation should be used forthe CHF predictions for the lower fuel assemblies of thereactor in the subchannel model of the RBMK-1500 fuel assembly.RRC KI and Bowring CHF correlations may be used for the upperfuel assemblies. For a single-channel model of the RBMK-1500fuel channel, Osmachkin, RRC KI and Bowring correlationsprovide the closest predictions and may be used for the CHFestimation. For the low coolant mass fluxes in the fuelchannel, Khabenski correlation can be applied.

The fourth chapter presents the verification of the CORETRANcode for the RBMK-1500 core analysis (HELIOS generated neutroncross section data, coupled CORETRAN 3-D neutron kineticscalculations and VIPRE-02 thermal hydraulic module). The modelwas verified against a number of RBMK-1500 plant data andtransient calculations. The new RBMK-1500 core model wassuccessfully applied in several safety assessment applications.A series of transient calculations, considered within the scopeof the RBMK-type reactor Safety Analysis Report (SAR), wereperformed. Several cases of the transient calculations arepresented in this chapter. The HELIOS/CORETRAN/VIPRE-02 coremodel for the RBMK-1500 is fully functional. The RBMK-1500 CPSlogic, added into the CORETRAN provides an adequate response tothe changes in the reactor parameters.

Chapters 5 and 6 describe the experiments and the analysisperformed on the coolability of particulate debris bed and meltpool during a postulated severe accident in the LWR. In theChapter 5, the coolability potential, offered by the presenceof a large number of the Control Rod Guide Tubes (CRGTs) in theBWR lower head is presented. The experimental investigationsfor the enhancement of coolability possible with CRGTs wereperformed on two experimental facilities: POMECO (POrous MEdiumCOolability) and COMECO (COrium MElt COolability). Theinfluence of the coolant supply through the CRGT on the debrisbed dryout heat flux, debris bed and melt pool quenching time,crust growth rate, etc. were examined. The heat removalcapacity offered by the presence of the CRGT was quantifiedwith the experimental data, obtained from the POMECO and COMECOfacilities. It was found that the presence of the CRGTs in thelower head of a BWR offers a substantial potential for heatremoval during a postulated severe accident. Additional 10-20kW of heat were removed from the POMECO and COMECO testsections through the CRGT. This corresponds to the average heatflux on the CRGT wall equal to 100-300 kW/m2.

In the Chapter 6 the ex-vessel particulate debris bedcoolability is investigated, considering the non-condensablegases released from the concrete ablation process. Theinfluence of the flow of the non-condensable gases on theprocess of quenching a hot porous debris bed was considered.The POMECO test facility was modified, adding the air supply atthe bottom of the test section, to simulate the noncondensablegas release. The process was investigated for both high and lowporosity debris beds. It was found that for the low porositybed composition the countercurrent flooding limit could beexceeded, which would degrade the quenching process for suchbed compositions. The experimental results were analyzed withseveral CCFL models, available in the literature.

Keywords:RBMK, light water reactor, core analysis,transient analysis, reactor dynamics, RIA, ATWS, critical heatflux, post-CHF, severe accidents, particulate debris beds, meltpool coolability, BWR, CRGT, dryout, quenching, CCFL, crustgrowth, solidification, water ingression, heat transfer.

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45

Thomson, Jim. "Cold Pasteurization Of Tender Coconut Water By A Batch And Flow Processes Using Glassbeads Coated With Phytochemicals Encapsulated Nano-Liposomes." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2330.

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Tender coconut water (TCW) is one of most consumed natural energy drinks. Although it is widely available in tropical countries, because of its natural health benefits it is increasingly consumed in other parts of the world. Therefore there has been an increased requirement for packaging and shipping. TCW is highly susceptible to microbial contamination during extraction and packaging, requiring pasteurization. Thermal pasteurization leads to loss of flavor and color of coconut water. The purpose of this study was to test the feasibility of a non-thermal method of pasteurization of TCW using natural antimicrobials like curcumin, eugenol, and d-limonene with curcumin. The non-thermal pasteurization method was developed in two different processes, i.e. a batch and flow-filter process. Batch cold pasteurization process was conducted by suspending liposome encapsulated antimicrobials immobilized on glassbeads in TCW at 4oC by shake flask assay. Maximum Reduction of Listeria monocytogenes and Escherichia coli W1485 in pasteurized TCW were observed to be 5 log CFU per ml of TCW within 7 days of incubation under the presence of nano-liposomes containing 50 mM of curcumin, d- limonene or eugenol. There was no change in color and aroma of TCW after 1 month of storage at 4oC. the flow filter cold pasteurization process was developed using filter medium coated with nano-liposomes encapsulated antimicrobial leading to extended release of the natural antimicrobial curcumin to the coconut water in 4oC. Listeria monocytogenes and E. coli W1485 were used as model organisms to test effectiveness of cold pasteurization. Reduction of L. monocytogenes and E. coli W1485 in pasteurized TCW was observed to be 5.2 and 4.5 log10CFU/ml of TCW respectively within 17.25 min of incubation under the presence of nano-liposomes containing 50 mM of curcumin. There was no change in color and aroma of TCW after 1 week of storage at 4oC.
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46

Schlenker, Markus Thomas [Verfasser], and R. [Akademischer Betreuer] Stieglitz. "Multi-physical Developments for Safety Related Investigations of Low Moderated Boiling Water Reactors / Markus Thomas Schlenker. Betreuer: R. Stieglitz." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1068263296/34.

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47

Gover, Rory Benjamin. "Experimental impact and finite element analysis of a composite, portable road safety barrier." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/62339/7/Rory_Gover_Thesis.pdf.

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This thesis provides an experimental and computational platform for investigating the performance and behaviour of water filled, plastic portable road safety barriers in an isolated impact scenario. A schedule of experimental impact tests were conducted assessing the impact response of an existing design of road safety barrier utilising a novel horizontal impact testing system. A coupled finite element and smooth particle hydrodynamic model of the barrier system was developed and validated against the results of the experimental tests. The validated model was subsequently used to assess the effect of certain composite materials on the impact performance of the water filled, portable road safety barrier system.
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48

Santos, Mónica Sofia Freitas dos. "Chemical Safety of Drinking Water Networks." Doctoral thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/87709.

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49

Santos, Mónica Sofia Freitas dos. "Chemical Safety of Drinking Water Networks." Tese, 2013. https://repositorio-aberto.up.pt/handle/10216/87709.

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50

Bordalo, Bernardo Daniel Antunes. "Water Heaters Electrovalves: Improvement of Safety Parameter." Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/76871.

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