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Burger, A. F. (Adriaan Francois). "Scheduling algorithms for routine maintenance of roads in maintenance wards of a gravel road network." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50446.
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Thesis (MScEng)--University of Stellenbosch, 2005.ENGLISH ABSTRACT: The study reported in this thesis focuses on the development of algorithms that can be used to schedule routine maintenance work in maintenance wards of a gravel road network, This was undertaken as part of the development of the Blading Optimisation Module of the Gravel Management System of the Provincial Government: Western Cape. Two scheduling algorithms were developed and mapped to a pilot object model on the computer. The algorithms and application interface takes account of the constraints and variables of routine maintenance that were identified through interviews with personnel of the five District Municipalities contained in the Western Cape. The algorithms are tested and evaluated using the pilot application. Based on the evaluation of the algorithms conclusions are drawn and recommendations are made.
AFRIKAANSE OPSOMMING: Die studie beskryf in hierdie tesis fokus op die ontwikkeling van algoritmes vir die skedulering van roetine instandhoudingswerk in instandhoudingswyke van 'n gruispadnetwerk. Dit is ondemeem tydens die ontwikkeling van die "Blading Optimisation Module" van die "Gravel Management System" van die Provinsiale Regering: Wes Kaap. Twee algoritmes is ontwikkel en afgebeeld op 'n loods-objekmodel op die rekenaar. Die algoritmes en toepassingskoppelvlak maak voorsiening vir die beperkings en veranderlikes wat geidentifiseer is tydens onderhoude met personeel van die distrikmunisipaliteite in die Wes Kaap. Die algoritmes is getoets en geevalueer met behulp van die loodstoepassing. Gevolgtrekkings en aanbevelings word gemaak op grond van die resultate van die evaluasie van die algoritmes.
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Li, Yiu-man, and 李耀文. "MPA dissertation: an analysis of the policy on the control of road-opening works in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31965003.
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Tolliver, Denver D. "The impacts of grain subterminals on rural highways." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54799.
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The problems associated with increased heavy grain truck traffic in rural regions were investigated. Both the short-run incremental costs of accelerated pavement replacement and the long-run incremental costs of upgrading low-volume highways were considered. A set of demand and traffic models was formulated which projects the annual flow of grain from each production zone in an impact region to each elevator, allocates the flows among truck-types, computes the annual trips, gross vehicle weights and axle weights, and assigns the truck trips to the highway network. A set of highway models was also formulated which computes the equivalent single axle loads for each highway section in an impact region and estimates the incremental costs associated with subterminal traffic.
The impacts of a newly-formed subterminal-satellite elevator system in rural North Dakota were investigated. The results of the case study indicate that rural collector highways are likely to experience substantial localized impacts from subterminal development but the effects on principal arterials may be minimal. Altogether, $1.14 million in short-run costs and $8.41 million in long-run costs were projected for the impact region. However, the case study roads represent less than 2 percent of the rural arterial and collector highway mileage in the state. If the case-study network represents a microcosm of rural North Dakota, then the statewide short-run and long-run incremental costs may be in the vicinity of $57 million and $420 million respectively. However, regional variations within the state may result in either higher or lower costs for a given elevator system than those projected in the case study.Ph. D.
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Norris, Shaun Peter. "The adequacy of traffic control measures during road works." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/11520.
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Workers have the right to a safe working environment. This right is encapsulated in the Bill of Rights (1996) wherein strong emphasis is placed on the right to a healthy and safe work environment. The construction industry has been labeled as dangerous owing to regular incidents, serious accidents, and fatalities. Road workers’ safety is at high risk in road construction areas, as they perform their work activities alongside moving vehicles that are often large and sometimes moving at high speed. It was determined that very few secondary sources provided information regarding the safety of South African road construction workers. Therefore, the knowledge obtained from this study contributes to the body of knowledge on the subject matter. To collect data, three descriptive surveys were conducted on two different road construction projects within the Eastern Cape. The survey participants included engineering consultants, contractors, traffic safety officers, general road construction workers, as well as random motorists driving through the work zone. Further data was collected from a speed measuring instrument placed in the work zone of the Port Elizabeth. The findings of this research report indicate that road users are not cognizant of the risk to workers in the work zone and that signage and advance warning signs alone are not sufficient to slow motorists’ speed. A further significant threat to road worker safety, is plant operator visibility. This study recommends that government and construction firms educate the public regarding the risks associated with speeding through a work zone. Construction firms should use electronic speed measuring devices prior to the work zone to make road users aware of their speed in relation to the speed limit. To limit plant related accidents, companies should install sensors or cameras on the rear and side panels of plant, so that plant operators have all round vision. Furthermore, road workers could be educated on the controlled use of their mobile phones to reduce the risks associated with the use of mobile phones inside work zones.
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Nicholls, Stephen John. "The effect of South African provincial road condition on the efficiency of forest product transport." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50146.
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Thesis (MScFor)--Stellenbosch University, 2004.ENGLISH ABSTRACT: The context of the study is concern over declining provincial road condition due to insufficient government funding of road maintenance. These roads are by their public nature used by a wide variety of commercial and private interests contributing a variety of axle loads. There was no information available on the use of these roads by forest companies and the road conditions. Consequently a survey was conducted to determine condition and length of each segment of provincial road in use by forestry companies and the volume of wood transported over them. In addition data was gathered on other users and their contribution to the volume transported over each section. The questionnaire indicated that the provincial roads are in a poor state. The literature review suggested a significant reduction in total cost of transport can be achieved by maintaining or rebuilding these roads. South African forest companies provide the majority of the heaviest axle loading to these roads and must theretore take responsibility tor damage caused to them. Also a variety of forest companies use the same roads and consequently collaborative studies between companies are needed. A modified Dijkstra's algorithm was used to quantify the effect of the condition of South African provincial roads on the efficiency of the transport ottorest products. The model requires digitised raster road and forest map layers combined with transport vehicle specification as input. The products of the model are optimum routes from all source points to a single exit point or sink, the total volume transported across all road nodes and the total cost to extract all wood from a map section. This output allows managers to identify critical roads tor management attention and make tentative estimates of possible reductions to total cost by altering the road condition. The manager is able to test the sensitivity of the solution to changes in variables and gain a better overall picture of the interactions within the system. The model results, and improved understanding, will provide input to more specific and collaborative studies. South African forest managers can respond to the poor provincial road network by conducting ad hue maintenance to these roads to prevent them becoming completely impassable or to rebuild them to their design state and maintain them at that state. The cost of taking no actions is that these roads would eventually become impassable. The road network model determined that, for the study area, a unilateral decision to rebuild and maintain all roads would result in a net increase in transport costs ofR 2 million/year. When compared to the cost of ad hue road improvements for the same area of R 8 million it is obvious that proper road management is a better option. It was shown that 75% of the reduction in total cost is generated by improving only 31 % of the provincial road surface. Consequently, by improving selected roads (20% of the total provincial road network for the area) it was possible to generate a net cost R 2.9 million lower than if the roads were left as they are. If reductions in operating costs are included the net cost to the forest industry is R 3.1 million/year lower than leaving the roads as they are. In addition to the cost being lower, an improved road network would be in place and the current ad hue spending would be unnecessary. On a larger scale it was estimated that poor provincial road management costs the industry as a whole R 26 million or R 1.52/m3/year. This money can be used to offset the costs of maintaining and upgrading roads. It is therefore concluded that the South African forest industry needs to assess its policy on provincial road management and become more active in the managing of these roads. The tool developed and presented is intended as a prototype decision support tool in developing future policies.
AFRIKAANSE OPSOMMING: Die inhoud van hierdie studie handelaar die verval van provinsiale paaie as gevolg van die regering se onvoldoende fondse vir die instandhouding van die paaie. Hierdie paaie word as gevolg van hulle publieke aard deur 'n wye verskeidenheid kommersiële en private belange gebruik, wat bydra tot 'n verskeidenheid van asladings. Daar was geen inligting oor die bosbou maatskappye se gebruik van paaie of die toestand van die paaie beskikbaar nie. Gevolglik is 'n opname gemaak 0111 die kondisie en lengte van elke segment van die paaie wat deur die bosbou maatskappye gebruik word, vas te stel, asook die volume hout wat oor die paaie vervoer word. Data oor ander verbruikers van die paaie is verder ingesamel, asook hul bydrae tot die volume wat oor die paaie vervoer word. Die vraelys het aangedui dat die provinsiale paaie in 'n baie swak toestand is. 'n Literatuurstudie het getoon dat 'n beduidende daling in die totale vervoerkoste moontlik is deur hierdie paaie te onderhou afoor te bou. Die Suid-Afrikaanse bosbou maatskappye voorsien die meerderheid van die swaarste asladings op hierdie paaie en moet dus verantwoordelikheid neem vir beskadigde paaie, 'n Verskeidenheid bosbou maatskappye gebruik die paaie; gevolglik is gesamentlike studies tussen die maatskappye ook nodig. 'n Aangepaste Dijkstra algoritme is gebruik om die effek van die toestand van Suid- Afrikaanse provinsiale paaie op die effektiwiteit van die vervoer van bosbou produkte, vas te stel. Hierdie model benodig digitale inligting oor die hoofen bosbou paaie, asook die spesifikasies van die voertuie wat gebruik word. Die resultaat van die model is die optimale roetes vanaf alle bronpunt oorspronge tot by 'n enkele bestemming, die totale volume vervoer oor al die padnodusse en die totale koste verbonde aan die verwydering van alle hout uit 'n afgemerkte seksie op die kaart. Hierdie produk of result ate stel bestuurders in staat 0111 kritieke paaie vir aandag te identitiseer en om tentatiewe voorspellings van moontlike afname in die totale kostes te maak indien die toestande van paaie verbeter sou word. Die bestuurder kan die sensitiwiteit van die oplossing vir variasie in die veranderlikes toets en sodoende 'n beter geheelbeeld kry van die interaksie binne die sisteem. Die resultate van die model en n beter begrip daarvan, kan insterte lewer in meer spesitieke studies en gesamentlike studies tussen maatskappye. Suid Afrikaanse bosbou bestuurders kan teen die swak provinsiale padnetwerk optree deur ad hoc instandhouding toe te pas op hierdie paaie om te voorkom dat hulle totaal en alonbegaanbaar word. Ofhulle kan die paaie restoureer tot hul oorspronklike toestand en hulle dan in stand hou. Die kostes daaraan verbonde om nie op te tree nie, is dat hierdie paaie uiteindelik on-gaanbaar sal word. Die padnetwerkmodel het gewys dat vir die spesitieke studie area, 'n eenparige besluit 0111 alle paaie te herbou en onderhou, 'n algehele toename in vervoerkostes van R2 miljoen/jaar tot gevolg sal hê. Wanneer dit vergelyk word met die R8 miljoen wat die ad hoc padverbeterings kos, is dit duidelik dat geskikte padbestuur 'n beter opsie is. Daar is bewys dat 75% van die daling in totale kostes genereer kan word deur verbeteringe aan die oppervlaktes van slegs 31% van die provinsiale paaie te maak. Gevolglik was dit moontlik om netto kostes van R2,9 miljoen ruinder te genereer as vanneer geen instandhouding gedoen is nie. Dit is bewerkstellig deur verbeteringe aan geselekteerde paaie aante bring (20% van die totale provinsiale padnetwerk vir die area.) As die daling in bedryfskoste ingesluit is, sal die netto koste vir die bedryf R3.1 millioen/jaar ruinder wees as om die paaie so te los sonder enige aandag. Verder, tot laer koste sal daar 'n verbeterde pad netwerk in plek wees en die huidige ad hoc spandeering aan die paaie nie meer nodig wees nie. Op groot skaal, is die benaderd voorspelling dat 'n swak provinsialepadbestuurstelsel die bosbou bedryf R26 millioen of R 1.52/m3 uit die sakjaag. Hiedie misbruikde geld kan eerder teruggeploeg word in pad onderhoud en opgradeerings werksaamhede. Dit is dus nodig dat die bosbou bedryf sy beleid weer in oonskou moet neem in verband met die bestuur van provinsiale paaie en ook meer aktief die voortou sal moet neem in die instandhoudind van provinsiale paaie. Die metodiek hier ontwikkel kan 'n inleidende doel dien in die ontwikkeling van toekoemstige besluit neeming rakend die bestuur van provinsiale paaie.
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BONKAT, BARNABAS NANPAK. "ANALYTICAL PROCEDURE FOR EVALUATING ROADWAY UPGRADING STRATEGY FOR LOW-VOLUME HIGHWAYS." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187926.
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The purpose of this research was to develop a simplified analytical procedure for determining the optimal timing for upgrading low-volume roads in developing countries. Most roadway upgradings from gravel to surface treated and to asphaltic concrete are carried out when total transport cost on a road becomes high as a result of high traffic and the consequent rapid deterioration of the roadway. Adequate timing of upgrading strategies ensures effective use of resources and lower total transport cost. This study examined existing systems, models, and approaches for estimating total transport cost components. An analytical procedure was then developed using a decision-tree concept to delineate all possible upgrading strategies within a plan period. The decision-tree concept depicts all the possible upgrading strategies within a plan period with decisions on roadway upgrading made at certain decision intervals. The total transport cost of the upgrading strategies is evaluated to establish the optimal strategies and traffic warrants for improving a roadway surface. A computer program PVMNT was written to facilitate the computation of the total transport cost. A case study was presented to demonstrate the application of the analytical procedure. The case study revealed interesting results on the changes of optimal upgrading strategies with changes in base traffic volume and growth rate. However, general conclusions could not be drawn based on the results of the case study. These results, as well as the analytical procedure, should be of interest to engineers responsible for providing low-volume roads in developing countries.
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Karim, Hawzheen. "Improved Road Design for Future Maintenance - Analysis of Road Barrier Repair Costs." Licentiate thesis, Stockholm : Division of Highway Engineering, Royal Institute of Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9260.
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司徒雪雯 and Suet-man Helen Szeto. "Outsourcing of contract management and works supervision of road network maintenance in Highways Department." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31966998.
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Supawiwat, Nutthapon. "A study on road slope management system considering maintenance and repair strategy." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144540.
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Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第11867号
工博第2560号
新制||工||1358(附属図書館)
23647
UT51-2005-N701
京都大学大学院工学研究科土木システム工学専攻
(主査)教授 大西 有三, 教授 大津 宏康, 教授 中北 英一
学位規則第4条第1項該当
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Karim, Hawzheen. "Road Design for Future Maintenance : Life-cycle Cost Analyses for Road Barriers." Doctoral thesis, Högskolan Dalarna, Vägteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:du-5474.
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The cost of a road construction over its service life is a function of design, quality of construction as well as maintenance strategies and operations. An optimal life-cycle cost for a road requires evaluations of the above mentioned components. Unfortunately, road designers often neglect a very important aspect, namely, the possibility to perform future maintenance activities. Focus is mainly directed towards other aspects such as investment costs, traffic safety, aesthetic appearance, regional development and environmental effects. This doctoral thesis presents the results of a research project aimed to increase consideration of road maintenance aspects in the planning and design process. The following subgoals were established: Identify the obstacles that prevent adequate consideration of future maintenance during the road planning and design process; and Examine optimisation of life-cycle costs as an approach towards increased efficiency during the road planning and design process. The research project started with a literature review aimed at evaluating the extent to which maintenance aspects are considered during road planning and design as an improvement potential for maintenance efficiency. Efforts made by road authorities to increase efficiency, especially maintenance efficiency, were evaluated. The results indicated that all the evaluated efforts had one thing in common, namely ignorance of the interrelationship between geometrical road design and maintenance as an effective tool to increase maintenance efficiency. Focus has mainly been on improving operating practises and maintenance procedures. This fact might also explain why some efforts to increase maintenance efficiency have been less successful. An investigation was conducted to identify the problems and difficulties, which obstruct due consideration of maintainability during the road planning and design process. A method called “Change Analysis” was used to analyse data collected during interviews with experts in road design and maintenance. The study indicated a complex combination of problems which result in inadequate consideration of maintenance aspects when planning and designing roads. The identified problems were classified into six categories: insufficient consulting, insufficient knowledge, regulations and specifications without consideration of maintenance aspects, insufficient planning and design activities, inadequate organisation and demands from other authorities. Several urgent needs for changes to eliminate these problems were identified. One of the problems identified in the above mentioned study as an obstacle for due consideration of maintenance aspects during road design was the absence of a model for calculating life-cycle costs for roads. Because of this lack of knowledge, the research project focused on implementing a new approach for calculating and analysing life-cycle costs for roads with emphasis on the relationship between road design and road maintainability. Road barriers were chosen as an example. The ambition is to develop this approach to cover other road components at a later stage. A study was conducted to quantify repair rates for barriers and associated repair costs as one of the major maintenance costs for road barriers. A method called “Case Study Research Method” was used to analyse the effect of several factors on barrier repairs costs, such as barrier type, road type, posted speed and seasonal effect. The analyses were based on documented data associated with 1625 repairs conducted in four different geographical regions in Sweden during 2006. A model for calculation of average repair costs per vehicle kilometres was created. Significant differences in the barrier repair costs were found between the studied barrier types. In another study, the injuries associated with road barrier collisions and the corresponding influencing factors were analysed. The analyses in this study were based on documented data from actual barrier collisions between 2005 and 2008 in Sweden. The result was used to calculate the cost for injuries associated with barrier collisions as a part of the socio-economic cost for road barriers. The results showed significant differences in the number of injuries associated with collisions with different barrier types. To calculate and analyse life-cycle costs for road barriers a new approach was developed based on a method called “Activity-based Life-cycle Costing”. By modelling uncertainties, the presented approach gives a possibility to identify and analyse factors crucial for optimising life-cycle costs. The study showed a great potential to increase road maintenance efficiency through road design. It also showed that road components with low investment costs might not be the best choice when including maintenance and socio-economic aspects. The difficulties and problems faced during the collection of data for calculating life-cycle costs for road barriers indicated a great need for improving current data collecting and archiving procedures. The research focused on Swedish road planning and design. However, the conclusions can be applied to other Nordic countries, where weather conditions and road design practices are similar. The general methodological approaches used in this research project may be applied also to other studies.
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Stephenson, Gregory John. "Use of stone mastic asphalt mixtures in road pavement maintenance and construction." Thesis, Queensland University of Technology, 2002.
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Graham, Tennille. "Economics of protecting road infrastructure from dryland salinity in Western Australia." University of Western Australia. School of Agricultural and Resource Economics, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0207.
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[Truncated abstract] The salinisation of agricultural land, urban infrastructure and natural habitat is a serious and increasing problem in southern Australia. Government funding has been allocated to the problem to attempt to reduce substantial costs associated with degradation of agricultural and non-agricultural assets. Nevertheless, Government funding has been small relative to the size of the problem and therefore expenditure needs to be carefully targeted to interventions that will achieve the greatest net benefits. For intervention to be justified, the level of salinity resulting from private landholder decisions must exceed the level that is optimal from the point of view of society as a whole, and the costs of government intervention must be less than the benefits gained by society. This study aims to identify situations when government intervention is justified to manage dryland salinity that threatens to affect road infrastructure (a public asset). A key gap in the environmental economics literature is research that considers dryland salinity as a pollution that has off-site impacts on public assets. This research developed two hydrological/economic models to achieve this objective. The first was a simple economic model representing external costs from dryland salinity. This model was used to identify those variables that have the biggest impact on the net-benefits possible from government intervention. The second model was a combined hydro/economic model that represents the external costs from dryland salinity on road infrastructure. The hydrological component of the model applied the method of metamodelling to simplify a complex, simulation model to equations that could be easily included in the economic model. The key variables that have the biggest impact on net-benefits of dryland salinity mitigation were the value of the off-site asset and the time lag before the onset of dryland salinity in the absence of intervention. ... In the case study of dryland salinity management in the Date Creek subcatchment of Western Australia, the economics of vegetation-based and engineering strategies were investigated for road infrastructure. In general, the engineering strategies were more economically beneficial than vegetation-based strategies. In the case-study catchment, the cost of dryland salinity affecting roads was low relative to the cost to agricultural land. Nevertheless, some additional change in land management to reduce impacts on roads (beyond the changes justified by agricultural land alone) was found to be optimal in some cases. Reinforcing the results from the simple model, a key factor influencing the economics of dryland salinity management was the urgency of the problem. If costs from dryland salinity were not expected to occur until 30 years or more, the optimal response in the short-term was to do nothing. Overall, the study highlights the need for governments to undertake comprehensive and case-specific analysis before committing resources to the management of dryland salinity affecting roads. There were many scenarios in the modelling analysis where the benefits of interventions would not be sufficient to justify action.
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Cheung, Yui-fai, and 張銳輝. "The lane rental policy initiative in Hong Kong: a case study." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31964424.
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Kubová, Simona. "Poruchy mostních vozovek a jejich příčiny." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226620.
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As part of my master's thesis I have conducted a visual inspection and record failures of bridge roadway at selected highway bridges, roads D47, D3 and D8 and photographic documentation, which is included in Annex. Also I have based on their speeches and documents the results of control tests determine their causes and to propose appropriate repair or maintenance.
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Krapf, Carlyn Nicole. "Stress relaxation of stainless steel rods for bridge pier cap shear strengthening." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33859.
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This thesis examines the stress relaxation phenomenon that may occur in stainless steel rods that are used as part of an all-stainless steel externally post-tensioned rod system for strengthening reinforced concrete pier caps in shear. An overview of the stress relaxation phenomenon and its modeling is presented. Previous work on stress relaxation of stainless steel is reviewed and used to select an appropriate stress relaxation model to analyze the stress relaxation data obtained from experiments performed during this research. An experimental program utilizing six specimens of Type 304/304L stainless steel stainless steel rods similar to those likely to be candidates for pier cap rehabilitation is presented, and the data are analyzed using the model identified from the review. This model reasonably captures the behavior of the resulting stress relaxation with time, and calculates stress values that are fairly close to those obtained experimentally. Using this model to predict long-term stress losses in a service environment, guidelines for design and installation of the post-tensioned stainless steel rods are proposed.
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Alfelor, Roemer Matubis. "Optimal maintenance frequencies for unpaved roads." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/118818.
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Kalombaris, A. "Structural maintenance assessment and performance of minor roads." Thesis, University of Hertfordshire, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276181.
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Al-kaabi, Hamad A. "Airlines' maintenance, repair and overhaul (MRO) configurations." Thesis, Cardiff University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437225.
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Huaco, Daniel R. "Decision support for slope construction and repair activities an asset management building block /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5780.
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Thesis (M.S.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 3, 2008) Includes bibliographical references.
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Pan, Ju-Kun. "In-service pavement performance and maintenance strategies for minor roads." Thesis, University of Hertfordshire, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387139.
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Fofang, Veronica. "Strategies for construction and maintenance of rural roads in Cameroon." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/66370.
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Mahavier, Kendall Caitlin Alexandra. "Patterns in Road Maintenance: An Analysis of San Diego Roads." Oberlin College Honors Theses / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1526393989343466.
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Bridges, Michael R. "Optimally funding Army Installation repair and maintenance activities." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA341063.
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Thesis (M.S. in Operations Research) Naval Postgraduate School, September 1997."September 1997." Thesis advisor(s): Robert F. Dell. Includes bibliographical references (p. 43-44). Also available online.
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Nikou, Vasilios 1972. "Welded repair and maintenance in the space environment." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/91796.
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Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003.Includes bibliographical references (leaves 73-75).
by Vasilios Nikou.
Nav.E.
S.M.
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Kelly, Annette. "Comparative analysis of intermediate level maintenance repair process." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FKelly.pdf.
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Adé, Kémy. "Kupffer Cell Maintenance in Tissue Repair and Ageing." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS312.
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Les cellules de Kupffer (KCs) sont les macrophages résidents du foie. Phagocytes professionnels, ils sont au cœur du système immunitaire inné, première ligne de défense de l’organisme contre les agressions. Ils participent également au maintien de l’homéostasie tissulaire. Des travaux récents ont permis de comprendre leur origine. On sait maintenant que, à l’instar de la majorité des macrophages résidant dans les tissus, les KCs émergent durant la vie embryonnaire à partir des précurseurs érythro-myeloïdes (EMP), colonisent le foie durant le développement et y persistent à l’âge adulte. Cependant, en cas d’inflammation, ils sont rejoints par des macrophages différenciés à partir des monocytes circulants descendants des cellules souches hématopoïétiques. J’ai étudié la capacité des KCs à persister tout au long de la vie, y compris chez des souris gériatriques. En utilisant la cytométrie en flux et des techniques de traçage de lignées, j’ai montré que la densité des KCs diminuait avec l’âge sans compensation par les monocytes circulants. Un séquençage ARN, l’analyse de mutants TicamLPS2 et des expériences d’inflammation répétées induites par un analogue viral ont mis en lumière le possible rôle de l’inflammation dans ce phénotype. Ce dernier corrélait avec des altérations fonctionnelles. L’étude de la persistance des KCs dans un modèle de lésion aiguë du foie induite par le paracétamol et après déplétion des KCs par un antagoniste du récepteur CSF1R a montré que les KCs étaient capables de persister ou se reconstituer sans contribution de la circulation. Ces expériences établissent des outils pour une caractérisation des fonctions des KCs en contexte pathologiqueKupffer cells (KCs) are resident macrophages of the liver. Professional phagocytes of the innate immune system, they take part in the first line of defence against infections and injury. They also actively regulate liver homeostasis. Recent works have elucidated their origin. We now know that, like most other tissue resident macrophages, KCs develop during embryonic life from Erythro-Myeloid Progenitors (EMPs), seed the liver during development and persist there in adulthood. During inflammation, however, they can be joined by recently differentiated macrophages that arise from circulating monocytes belonging to the Haematopoietic Stem Cell (HSC) descendance. Here I studied the ability of mouse KCs to maintain themselves throughout life, and into old age. Using flow cytometry and fate mapping strategies, we showed that KC density decreased over time and was not compensated by recruitment of circulating cells. RNA sequencing, analysis of TicamLPS2 mutants and Poly (I:C)-induced repeated inflammation experiments highlighted the contribution of inflammation to the ageing phenotype. This phenotype correlated with lipid and senescent cell accumulation. We further studied KC maintenance in acetaminophen induced liver injury and after depletion induced by a CSF1R antagonist. In both contexts, KCs were able to maintain themselves through local proliferation without significant input from circulating cells. These experiments will provide a framework for the better characterisation of KC functions in injury and disease
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Qiu, Ju. "Work domain modeling to support winter road maintenance operations." Diss., University of Iowa, 2008. http://ir.uiowa.edu/etd/17.
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Obaidi, Hadel Ibraheem Ahmad. "Development of innovative pothole repair materials using induction heating technology." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/55281/.
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Millions are spent by authorities to maintain and repair the world's potholes. In addition to the direct costs, they can also lead to damaged vehicles and an accelerated deterioration of the road system. The potholes create traffic risks that lead to the daily loss of hundreds of work hours for drivers and passengers. Many road crews are not familiar with the proper materials and methods for pothole repair. Correct selection of pothole patching materials and proper application of repair procedures can greatly increase the longevity of pothole repairs, lead to fewer driver frustrations, and lower road maintenance budgets. The present study aims to develop innovative materials to repair of potholes by using induction heating technology. Three innovative patching materials to repair potholes are proposed, assessed and compared with conventional pothole patching materials. The first material is a combination of a prefabricated asphalt tile and a bonding layer that can be placed into a sanitised pothole and bonded by applying electromagnetic induction heating. The second material involves using prefabricated asphalt pellets to directly fill a pothole and then heated by induction. The third material comprises (1) prefabrication of binder pellets containing bitumen and steel wool that has been coated with a shell to avoid them sticking to each other; (2) the development of a mobile induction heating mixer that can mix the binder pellets with cold aggregate on-site before directly filling a pothole and compacting the mixture. In this research, their tensile and shear strength properties were assessed and demonstrated by repairing simulated potholes on testing slabs and subjected them to wheel tracking tests. The innovative patching materials showed excellent durability higher than a road repaired with cold mix asphalt. Furthermore, the innovative patching materials have been evaluated from economic and environmental standpoints and compared results with conventional hot mix and cold mix. These proposed patching materials have been applied by different raw materials and procedures, and have importance of properties that performed by laboratory tests. Based on the results of loaded wheel test, the service life of each patching materials has been calculated. An inventory was prepared to help quantify the energy requirements, material inputs, and emissions produced during production of raw materials, prefabrication of each product and their final installation. The requisite data was obtained from various sources in the literature. Two maintenance hypothesis were considered. The results showed that three innovative patching materials may be more sustainable and could reduce cost, energy usage and CO2 emissions over time in agreement with hypothesis 1. However, they may cause to increase the economic and environmental impacts over time in agreement with hypothesis 2.
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Toves, Peter Rocky. "Evaluating Success Factors in Implementing E-Maintenance in Maintenance, Repair, and Overhaul (MRO) Organizations." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/767.
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Despite more than a decade-long process to transition aircraft maintenance practices from paper-to electronic-based systems, some organizations remain unable to complete this transition. Researchers have indicated that while organizations have invested resources in technology improvements, there remains a limited understanding of the factors that contribute to effectively managing technology-enabled change. The purpose of this case study was to identify and explore socio-technical (ST) factors that inhibit an effective transition from a paper-based system to an electronic-based system for aircraft maintenance. A conceptual model applying theories of change management, technology acceptance, systems thinking, and ST theory informed the research. Thirteen participants provided data via semistructured interviews, field observations, follow-up interviews, other documentation, and a questionnaire. Data were analyzed with open and axial coding techniques to identify themes, which were then crosschecked and triangulated with observation and follow-up interview data. Findings revealed communication issues, a fundamental misconception in training, and a false assumption that all personnel easily acquire computer literacy. Benefits gained from this study should assist maintenance, repair, and overall (MRO) organizations within the Department of Defense to improve current and future technology implementation as the research underscores real-life issues from a comparable organization. The implications for positive social change provide a greater understanding of technology-enabled change and contribute to the development of best practices for technology initiatives that address common ST issues in the MRO workplace.
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Luyt, Leslie. "Automated grid fault detection and repair." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1006693.
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With the rise in interest in the field of grid and cloud computing, it is becoming increasingly necessary for the grid to be easily maintainable. This maintenance of the grid and grid services can be made easier by using an automated system to monitor and repair the grid as necessary. We propose a novel system to perform automated monitoring and repair of grid systems. To the best of our knowledge, no such systems exist. The results show that certain faults can be easily detected and repaired.TeX
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Gamede, Cyril Vuyani. "Boiler maintenance using expert systems." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/18798.
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This research explores the application of expert systems to the maintenance of boilers, are as follows: and its main objectives [1] To explore the application of expert systems in the maintenance of boilers. [2] To simplify the task of boiler maintenance with the help of expert systems. [3] To improve the skills of boiler maintenance workers through the knowledge 'captured ' or 'preserved' by expert systems. [4] To minimise errors which may cost time, money, effort and possible risk of injury to boiler maintenance personnel. [5] To develop a prototype expert system which can advise and assist boiler maintenance personnel. [6) To contribute to research in the application of expert systems in the field of engineering.
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De, Wet Vorster Hendrik. "An analysis of the effectiveness of the asset maintenance plan at Spoornet : case study : class diesel locomotives (traction and rolling stock)." Thesis, Peninsula Technikon, 2001. http://hdl.handle.net/20.500.11838/1019.
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Thesis (MTech (Business Administration))--Peninsula Technikon, 2001Maintenance of locomotives is the main function of Bellville Locomotive Traction Depot in the Western Cape. Therefore, it is important to have a sound maintenance plan in place, to prevent a negative impact on the availability and reliability of locomotive supply for hauling power to train services. The purpose of the research is to determine the causes of the increased frequency of maintenance through a case study relating to 35-class locomotives. The abnormal increased frequency of wheel change and inter-bogie control repairs on 35-class diesel locomotives is investigated. A research survey was adopted, which included questionnaires and personal interviews based on the literature search. The target group is L&N section, which includes below-deck maintenance, overhaul and change out, repairs to locomotive bogies, frames, wheels, snubbers, inter-bogie control and traction motors. Sixteen people are responsible for all below-deck repairs and service of 52 locomotives. The results of the research will expose the shortcomings of the maintenance plan and propose solutions. This will be achieved by testing the effectiveness of the existing maintenance plan at Spoornet through the identification of the causes for the abnormal increase in wheel changes and inter-bogie control repairs on 35-class diesel locomotives. The outcome from this case study research will be to quantify the benefits arising from the effective application of a maintenance plan.
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An, Wei 1963. "Strengthening of concrete beams with composite plastic plates." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277246.
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This study investigates the feasibility of strengthening reinforced concrete beams with epoxy-bonded Glass-Fiber-Reinforced-Plastic (GFRP) plates. The composite plate is epoxy-bonded to the tension flange of the beam to increase its stiffness and strength. Seven rectangular and one T-beam, retrofitted with composite plates, were tested to failure under symmetrical 4-point bending. The load versus deflection and the load versus strain in the composite plate, steel rebar and the extreme compression fiber of concrete were measured and plotted for the midspan section throughout the entire range of loading up to failure. Analytical models based on the equilibrium of forces and compatibility of deformations were developed to predict the stresses and deformations of the beam in the linear and nonlinear regions. The predicted and measured results correlated well. The analytical models were used in a parametric study to investigate the effects of design variables such as, plate area, plate strength and stiffness, reinforcement ratio, etc., on the moment-curvature relationships of typical rectangular and T cross sections.
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Alfar, E. "GIS-based pavement maintenance management model for local roads in the UK." Thesis, University of Salford, 2016. http://usir.salford.ac.uk/39679/.
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Roads represent a major long-term infrastructure investment. A well-managed and maintained road is therefore fundamental to the safety and availability of the road network as a whole. In carrying out pavement maintenance functions, Local Road Authorities face growing pressures arising from inadequate budgets and greater accountability, when many of the existing roads have reached the upper limits of their design life spans while being subjected to increasing traffic. There are many factors that influence the decision making process in pavement maintenance management, including road surface conditions, safety, traffic loading, cost, funding and prioritisation decisions, hence an efficient approach is vital to ensure optimisation and a satisfactory trade-off between conflicting factors. A Multi-criteria Decision Making (MCDM) approach is used to handle the trade-off between conflicting factors. It is processed in the Analytical Hierarchy Process (AHP) using Excel software, and the database developed in Excel is then imported into GIS in order to allow ease of query, analysis and visualisation of results. The main key output of this research will be the development of a GIS-based pavement maintenance management model to support decision making in pavement maintenance management. The most important factors influencing decision making in pavement maintenance management are established through a nationwide questionnaire survey, which is undertaken among the UK Local Authorities’ pavement maintenance experts. 14 factors were identified, which are: Remaining Service Life, Road Condition Indicator (RCI), Type of Deterioration, Observed Deterioration Rate, Traffic Diversion, Importance of Road/Classification, Annual Average Daily Traffic (AADT), Possible Conflict or Overlap with Other Road Works, Risk of failure, Safety Concern, Accident Rate (related to surface condition), Scheme Cost, Available Budget/Funding and Whole Life-Cycle Cost. Interviews were also conducted with experts in pavement maintenance within different Local Road Authorities to justify the rated factors affecting pavement maintenance prioritisation. The case study approach was adopted, based on Runnymede District roads within the Surrey County Council, for developing and testing the GIS-based decision support model. The output model was validated through interviews with four experts in pavement maintenance as target end-users, and the model was judged as a rational, simple and usable appropriate tool for network analysis as GIS. However, a risk of inadequate budgets might limit the practicability of the model.
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Haidvogel, Robert F. "The Afloat maintenance Command: organizational and funding issues in Navy ship maintenance, repair, and modernization." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23521.
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Approved for public release; distribution is unlimitedThe goal of current Navy surface ship maintenance and repair strategy is to sustain readiness and to maximize both combat capability and the amount of time ships are available for employment during their lifetime. The established organizational framework of the Navy to perform this task includes a complex array of activities that are effective overall, but at the expense of efficiency. The current drawdown in budget resources requires that the goals of ship maintenance and modernization be met with improved efficiency. The Afloat Maintenance Command is a proposal to restructure the existing maintenance hierarchy. Improvements in the process of maintenance and modernization are incorporated in the Afloat Maintenance Command through the elimination of redundancies in capabilities and the improvement of funding flows to enhance organizational efficiency and effectiveness. This thesis will provide an overview of the Afloat Maintenance Command and its possible organization in consolidating assets from existing maintenance activities. Additionally, funding alternatives for the Afloat Maintenance Command will be developed and assessed.
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盧英明 and Ying-ming Lo. "Analysis of maintenance service figures of domestic towngas appliance." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31976645.
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Iu, Lai-ling. "Slope mainteannce [i.e. maintenance] and repair works in Hong Kong." Click to view the E-thesis via HKU Scholars Hub, 2005. http://lookup.lib.hku.hk/lookup/bib/B37935392.
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Aman, Shah Shahani. "System level airborne avionics prognostics for maintenance, repair and overhaul." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/11844.
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The aim of this study is to propose an alternative approach in prognostics for
airborne avionics system in order to enhance maintenance process and aircraft
availability. The objectives are to analyse the dependency of avionic systems
for fault propagation behaviour degradation, research and develop methods to
predict the remaining useful life of avionics Line Replaceable Units (LRU),
research and develop methods to evaluate and predict the degradation
performances of avionic systems, and lastly to develop software simulation
systems to evaluate methods developed.
One of the many stakeholders in the aircraft lifecycle includes the Maintenance,
Repair and Overhaul (MRO) industry. The predictable logistics process to some
degree as an outcome of IVHM gives benefit to the MRO industry.
In this thesis, a new integrated numerical methodology called ‘System Level
Airborne Avionic Prognostics’ or SLAAP is developed; looking at a top level
solution in prognostics. Overall, this research consists of two main elements.
One is to thoroughly understand and analyse data that could be utilised.
Secondly, is to apply the developed methodology using the enhanced
prognostic methodology.
Readily available fault tree data is used to analyse the dependencies of each
component within the LRUs, and performance were simulated using the linear
Markov Model to estimate the time to failure. A hybrid approach prognostics
model is then integrated with the prognostics measures that include
environmental factors that contribute to the failure of a system, such as
temperature. This research attempts to use data that is closest to the data
available in the maintenance repair and overhaul industry.
Based on a case study on Enhanced Ground Proximity Warning System
(EGPWS), the prognostics methodology developed showed a sufficiently close
approximation to the Mean Time Before Failure (MTBF) data supplied by the Original Equipment Manufacturer (OEM). This validation gives confidence that
the proposed methodology will achieve its objectives and it should be further
developed for use in the systems design process.
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Anyala, Michael. "Investigation of the impact of climate change on road maintenance." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/2815/.
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The performance of roads is known to progressively reduce as a result of separate and interactive effects of climate and traffic. Existing decision support tools such as HDM-4, which are widely used to investigate long-term road maintenance strategies, utilise past climate data instead of future climate predictions. Uncertainties inherent in future climate predictions however imply that application of such tools could lead to outputs that are not robust in light of climate change. The objectives of the study were threefold: firstly, to develop a rut depth prediction model that considered potential effects of future climate; secondly, to formulate a framework for quantification of uncertainties; and finally, to demonstrate the application of the tools developed using a case study. The model was developed using data provided by the UK Highways Agency and UK Climate Impacts Programme. The methodology used was based on Bayesian regression. The developed model was found to perform better than the current asphalt surfacing rut depth model implemented in HDM-4 when future climate data was used. It was concluded that probabilistic outputs from the tools developed including deterioration rates, pavement condition and discounted maintenance costs for each maintenance strategy, and future climate and socio-economic scenarios provide a useful decision making framework for considering alternative strategies for road maintenance on the basis of the level of climate change risks that can be tolerated.
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Lia, Debora. "Role of alphaOGG1 in the Maintenance of Mitochondrial Physiology." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS125/document.
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Les mitochondries sont des structures uniques dans la cellule mammifère. Ces organites portent leur propre génome (ADN mitochondrial, ADNmt) qui se compose d'une petite molécule qui codifie pour 13 polypeptides de la chaîne de transport d'électrons (ETC), 22 ARNt et 2 gènes d'ARNr pour sa propre synthèse protéique. Le MTDNA est proposé pour être plus susceptible au stress oxydatif que le génome nucléaire (ADNn) parce que non seulement il manque d'histones protectrices, mais aussi en raison de sa proximité avec les complexes ETC qui sont les principaux producteurs de ROS dans les cellules de mammifères. Parmi tous les types de dommages à l'ADNmt, les dommages oxydatifs sont les plus répandus et, de loin, les mieux étudiés. La voie de réparation de l'excision de base (BER) est un mécanisme de réparation d'ADN conservé de façon évolutive qui répare les dommages de base d'ADN non volumineux. Puisque la guanine a le potentiel redox le plus bas de toute autre base dans l'ADN, elle est facilement oxydée à la 8-oxoguanine (8-oxoG) qui est l’altération la plus fréquente induite par les ROS sur les deux, l'ADNc et l'ADNmt. Si la fourche de réplication contourne le 8-oxoG avant son élimination, un A est souvent inséré sur le brin d'ADN opposé et les réplications subséquentes corrigent la transversion de G à T. Lorsqu'il est associé à la cytosine, le 8-oxoG est éliminé de l'ADN par l'ADN glycosylase de 8-oxoguanine (OGG1) qui, de cette manière, initie le procédé BER. OGG1 est une glycosylase de ménage bi fonctionnelle qui, conjointement avec d'autres enzymes BER différentes, est présente dans les compartiments nucléaires et mitochondriaux, soulignant l'importance de maintenir l'intégrité de l'ADNmt pour le fonctionnement cellulaire normal. Il a été démontré que la surexpression d'une version recombinante d'OGG1, spécifiquement destinée aux mitochondries par un signal de ciblage mitochondrial supplémentaire (MTS) (OGG1-MTS), protège les cellules d'un stress oxydatif, probablement en raison d'une efficacité accrue dans la réparation De 8-oxoG dans l'ADNmt. L'objectif principal de notre projet est d'élucider si la perte spécifique de l'activité de réparation 8-oxoG dans les mitochondries (mais pas dans le compartiment nucléaire) a un impact sur les fonctions organelles et / ou sur la viabilité cellulaire et aussi pour dévoiler le mécanisme / s Derrière les effets protecteurs d'OGG1 sur la physiologie mitochondriale et la maintenance d'ADNmtMitochondria are unique structures within the mammalian cell. These organelles carry their own genome (mitochondrial DNA, mtDNA) which consists of a small molecule that codifies for 13 polypeptides of the electron transport chain (ETC), 22 tRNA and 2 rRNA genes for its own protein synthesis. MtDNA is proposed to be more susceptible to oxidative stress than the nuclear genome (nDNA) because not only it lacks protective histones but also because of its proximity to ETC complexes which are the main ROS producers in mammalian cells. Among all the types of mtDNA damage, oxidative damage is the most prevalent and, by far, the best studied. Base excision repair (BER) pathway is an evolutionarily conserved DNA repair mechanism that repairs non-bulky DNA base damages. Since guanine has the lowest redox potential of any other bases in DNA, it is readily oxidized to 8-oxoguanine (8-oxoG) that is the most frequent alteration induced by ROS on both, nDNA and mtDNA. If the replication fork bypasses the 8-oxoG before its removal, an A is often inserted on the opposite DNA strand and subsequent replications fix the G to T transversion. When paired with cytosine, 8-oxoG is removed from DNA by the 8-oxoguanine DNA glycosylase (OGG1) that in such a way initiates the BER process. OGG1 is a bifunctional housekeeping glycosylase that, together with other various BER enzymes is present in both nuclear and mitochondrial compartments, highlighting the importance of maintaining mtDNA integrity for normal cellular functioning. It has been demonstrated that the overexpression of a recombinant version of OGG1, specifically targeted to mitochondria by an additional Mitochondrial Targeting Signal (MTS) (OGG1-MTS), protects the cells from an oxidative stress, likely due to an increased efficiency in the repair of 8-oxoG in mtDNA. The main goal of our project is to elucidate if the specific loss of 8-oxoG repair activity in mitochondria (but not in nuclear compartment) has an impact on the organelles’ functions and/or on cell viability and also to unveil the mechanism/s behind the protective effects of OGG1 on mitochondrial physiology and mtDNA maintenance
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Kumar, V. Bala. "The development and assessment of an analytical structural maintenance design system for roads." Thesis, University of Plymouth, 1985. http://hdl.handle.net/10026.1/2804.
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Previous work at Plymouth has shown the deflected shape as measured by the Deflectograph can be used to estimate the thickness of surfacing. This thesis extends the earlier work to develop relations between deflected shape and the stiffness and thickness of pavement layers. A literature study has been carried out to identify the factors causing the deterioration of flexible pavements. The literature study also assesses the various pavement evaluation equipment that is available and describes various methods of analysis and the interpretation of the pavement surface deflection shape that have been proposed. The properties of the materials of the various layers of the flexible pavement have been reviewed. Various structural models of a pavement are considered and the study indicates that the finite element method provides a most accurate prediction of actual pavement response to a moving wheel load. A 3D finite element model of a flexible pavement has been produced and partially validated with data obtained from the TRRL. A Fortran Programe has been developed to convert absolute deflections predicted by the 3D model into equivalent Deflectograph deflections. The model has been used to carry out parametric study to establish appropriate relationships between the deflected shape and material properties of the pavement layers. Relationships have been established to determine the thickness, modular ratio and modulus of the pavement layers and its support subgrade from measurement of the deflected shape. An Analytical Pavement Evaluation and Design System has been set up based on the relationships. The system has been validated by comparing the material properties obtained from the laboratory testing with those predicted by the design model using the Deflectograph measurements obtained from local roads with measurement of layer thickness and subgrade strength measured in-situ.
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Žůrek, Jakub. "Aplikace systému hospodaření s vozovkou (SHV) na silnicích II. a III. třídy Libereckého kraje." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409833.
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This master thesis deals with the pavement management system as a tool for a management and maintenance of the roads in the Liberec region. The aim is to collect road failures within the network pavement management system level on roads of 2nd and 3rd class. The resulting data will be used for evaluate pavement condition and make plans of pavement maintenance and rehabilitation in variants. Furthermore, the thesis deals with individual variants in the process of data evaluation when evaluating their suitability and accuracy. The theoretical part summarises the information needed to understand the functioning of the road management system, as well as a description of the software used to collect and subsequent work with the data. In the practical part are presented results of the thesis and moreover the questions arising from the goals set are answered.
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Yearby, Shedrick Dashun. "USMC Aviation Maintenance and Repair Cost for the H-1 Upgrade." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/6891.
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MBA Professional ReportApproved for public release, distribution unlimited
This research focuses on the Marine Corps Aviation Maintenance and Repair Cost for the H-1 Upgrade platform. Onsite visits with the Program Manager Air 276 (PMA-276), the Naval Supply Weapons Systems Support (NAVSUP WSS), the Defense Logistics Agency (DLA), and Marine Aviation Logistics Squadron 39 (MALS-39) are conducted to obtain information regarding readiness costs and efficiencies that have impacted the total cost for a transitioning aircraft in Marine aviation. PMA-276, NAVSUP WSS, DLA, and MALS-39 make up the H-1 Cross-Functional Team (CFT). The H-1 CFT provides actionable metrics and best practices that focus on cost concerns (programmatic, material, management, and execution) from all levels of aviation logistics and planning. Key areas of improvement or replication are identified through metric-based solutions that affect cost reductions throughout the AH-1Z and UH-1Y integration.
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Wood, Thomas L. "Evaluation of project selection techniques for pavement network maintenance and repair." Thesis, Monterey, California. Naval Postgraduate School, 1994. http://hdl.handle.net/10945/25909.
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Different approaches have been suggested for determining the optimal
mix of repair projects for a pavement network. These methods range from
random selection to sophisticated mathematical optimization models.
This paper presents an analysis of several questions regarding the
effectiveness of three possible selection methods.
First, the performance of three separate single year project selection
methods on different size networks is assessed over a broad funding spectrum.
The results indicate that as funding levels increase, the benefit obtained by
different selection methods converge. In addition, as the size of the network
increases, the convergence tends to occur at progressively lower funding levels.
Second, the effect of the performance prediction models on these same
selection methods is assessed by altering the coefficients of the models to predict both faster and slower deterioration of the network. The "select sets" of
projects created by priority ranking selection and Knapsack IP selection at three
separate funding levels are compared to determine how much variation is introduced by the changes in the performance prediction. With a 30%
acceleration and deceleration of the deterioration curves, there was little change
in the optimal project set created by either method.
Finally, a modified Monte Carlo model is used to assess the general
shape of the solution space. The results suggest that the solution space is relatively flat except in the immediate vicinity of the optimum. This, in turn,
suggests that a Monte Carlo approach to this problem would require a large
number of trials to approximate the optimum. This finding conceptually supports
findings in this study and others, as well as the intuitive observation, that random
maintenance and repair strategies perform poorly compared to more rational
approaches. Since only a few sets of repair projects are near the optimum, the
chances of a random selection matching one of these near optimal project sets are relatively small.
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Coxon, W. D. "Evaluation of models for decision making in inspection and repair maintenance." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/21151.
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There has been growth in the costs of maintenance over the last 40 years. This can be linked directly to the changes in production technology over that period of time. However. there has also been growth in the field of management science and operations research. Many models have been developed to assist the maintenance function in its decisions. However. it would appear from engineering journals and shop floor practice that these models are not well used. For this research the method of inspection and repair maintenance has been chosen. Mainly because it is one of the most widely used methods. The objectives of the research are as follows: (1) To investigate the state of the art of plant and equipment maintenance paying particular attention to the inspection and repair policy. (2) To establish what basic models are available for decision making in inspection and repair maintenance. (3) To establish how feasible and useful each of these models is in the practical engineering environment. (4) To consider factors in the implementation of a decision making model in the inspection and repair policy with particular reference to the most practical and feasible model investigated.
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Konda, Issa 1962. "Tractor repair and maintenance costs and management policies in Burkina Faso." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277842.
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Farm machinery management data were collected in Burkina Faso, for the prediction of repair and maintenance costs. Equations were developed to predict repair and maintenance costs of tractors, cane loaders, generators and motorpumps. The analysis of data revealed that tractor repair and maintenance appears a greater burden than predicted by the American and Australian data. Tractor trade-in was not prescribed by the rule of minimum total cost per unit tractor use. Farm machinery and power units were operated more than twice as long as in the United States. New machine purchase was discouraged by the current sugar prices on the local market.
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Toledo, Maria Luiza Guerra de. "Determination of the optimal periodic maintenance policy under imperfect repair assumption." Universidade Federal de Minas Gerais, 2014. http://hdl.handle.net/1843/BUOS-9KRG8A.
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An appropriate maintenance policy is essential to reduce expenses and risks related to repairable systems failures. The usual assumptions of minimal or perfect repair at failures are not suitable for many real systems, requiring the application of Imperfect Repair models. In this work, the classes Arithmetic Reduction of Age and Arithmetic Reduction of Intensity, proposed by Doyen and Gaudoin (2004) are explored. Likelihood functions for such models are derived, and the parameters are estimated, allowing to compute reliability indicators to forecast the future behavior of the failure process. Under the classic Imperfect Repair virtual age model presented by Kijima et al. (1988) (particular case of Aithmetic Reduction of Age class), a periodic Preventive Maintenance policy is proposed, which estimates optimal time intervals for Preventive Maintenance, in order to minimize (preventive and corrective) maintenance costs. Under a dynamic perspective, it is showed how this policy can be improved, using each failure observation in order to recalculate the optimal time to Preventive Maintenance for a particular system, considering the effect of the repair action. These policies are applicable to any Imperfect Repair model. Monte Carlo simulation studies are implemented in order to evaluate the performance of the proposed methods. Those methods are applied to a real situation regarding the maintenance of engines of off-road trucks used in a mining company. These results bring valuable information to support decision making regarding Preventive Maintenance policy..
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Peterson, Reginald E. "Exploring Customers' Perceptions of Third Party Maintenance, Repair, and Operating Programs." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2170.
Full textAbstract:
A survey of 25 industrial manufacturing organizations in the U. S. indicated that 70% of respondents experienced dissatisfaction with their outsourcing programs due to unfulfilled expectations, which caused negative continuance intentions. The purpose of this descriptive case study was to explore the experiences of customers who currently use 3PMRO outsourcing programs to determine what factors affect satisfaction levels in the Southern United States. The conceptual framework for this study was the expectancy disconfirmation paradigm, which connects consumer satisfaction level to the fulfillment of consumer expectations. Data were collected from interviews of 22 procurement professionals of maintenance, repair, and operating supplies; observations of 3PMRO supplier performance meetings; and the analysis of performance scorecard documents. Data were analyzed using pattern matching followed by thematic analysis. Three themes were identified through the data analysis that affected consumer satisfaction: inventory management services, utilization of outsourced labor resources, and total cost value of the 3PMRO program. According to results, satisfaction of 3PMRO consumers are based on the proper utilization of a 3PMRO program for the intended limitations of the organization, reduced MRO supply costs, improved inventory management strategies, and improved competitive advantage from the realignment of resources to focus on core competencies. Implications for positive social change include increased awareness of cradle-to-grave inventory management to prevent improper disposal of non-biodegradable materials into our environment.
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Alzubaidi, Hossein. "On rating of gravel roads." Doctoral thesis, KTH, Infrastructure and Planning, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3252.
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Barnhart, Cynthia. "Investigation of need for organized maintenance." Virtual Press, 1986. http://liblink.bsu.edu/uhtbin/catkey/450777.
Full textAbstract:
The benefits of maintenance have been known for centuries, and throughout history these benefits have been the basis for much discussion. Recently such benefits have been formally proposed in terms of scheduled or cyclical maintenance programs. These programs have been developed for important historic buildings; yet the same benefits can be applied to any house. This concept is the basis of this thesis.The thesis begins with a discussion of the obvious need for some maintenance program and describes the recent interest of local governments in some form of maintenance planning, discussing the benefits of an organized approach to maintenance. Next it briefly reviews the beginnings and history of maintenance theories and is followed by a discussion of maintenance as a level of conservation of building. Basic statistics about homeowners and the development of the survey are addressed, which leads to the presentation of compiled results of the survey and a interpretation of the data. The conclusion indicates a direction for the development of an organized maintenance plan.