Infrastructure deterioration has been attributed to insufficient maintenance budgets, lacking restoration strategies, deficient deterioration prediction techniques, and changing climatic conditions. Considering that the latter adds more challenges to the former, there has been a growing demand to develop and implement climate-informed infrastructure asset management strategies. However, quantifying the impact of the spatiotemporally varying climate metrics on infrastructure systems poses a serious challenge due to the associated complexities and relevant modelling uncertainties. As such, in lieu of complex physics-based simulations, the current study proposes a glass box data-driven framework for predicting infrastructure climate induced deterioration rates. The framework harnesses evolutionary computing, and specifically multigene genetic programming, to develop closed-form expressions that link infrastructure characteristics to relevant spatiotemporal climate indices and predict infrastructure deterioration rates. The framework consists of four steps: 1) data collection and preparation; 2) input integration; 3) feature selection; and 4) model development and result interpretation. To numerically demonstrate its utility, the proposed framework was applied to develop deterioration rate expressions of two different classes of concrete and steel bridges in Ontario, Canada. The developed predictive models reproduced the observed deterioration rate of both bridge classes with coefficient of determination (R2) values of 0.912 and 0.924 for the training subsets and 0.817 and 0.909 for the testing subsets of the concrete and steel bridges, respectively. Attributed to its generic nature, the framework can be applied to other infrastructure systems, with available historical deterioration data, to devise relevant effective asset management strategies and infrastructure restoration standards under future climate scenarios. / Thesis / Master of Applied Science (MASc)

Thesis. (M. Tech. (Faculty of Engineering and Technology, Dept. of Civil Engineering))--Vaal University of Technology, 2011 / In the past thirty years there has been a rapid deterioration of the road network in South Africa. As an attempt to address this challenge, a study was conducted on R34 between Vrede and Bothmas Pass Border. The aim of the study was to develop a pavement management system for road network maintenance to serve as a decision support tool to assist to improve the efficiency of making decisions, provide feedback as to the consequences of these decisions, ensure consistency of decisions made at different levels and improve the effectiveness of all decisions in terms of efficiency of results. The study focused on developing and testing pavement management system for road network maintenance. Consequently, visual condition inspections, non-destructive and semi-destructive tests were conducted on the field, data acquired, processed and analysed in accordance with guidelines stipulated in the Draft Technical Recommendations for Highways (TRH) 22 in order to draw conclusions. The data acquired included the surfacing assessments, structural assessments, functional assessments, traffic surveys, riding quality, falling weight deflectometer, mechanical rutting, material investigations and dynamic cone penetration. After analysis of the data, visual condition index was then calculated to be 40%. Visual condition index was then used to determine the action required towards rehabilitating the road. After consultation with guidelines contained in the TRH22, it was concluded that the pavement treatment needed for the road was Rehabilitation. It was then concluded that PMS developed would provide key performance indicators to assist with decision support system and that it is also suitable for road network applications ranging from national roads, provincial roads, regional or district arterial and collector / distributor networks in SA. The municipalities and other road maintenance agencies were then recommended to utilise the “easy to use” developed pavement management system as a decision support tool in their maintenance programmes.

<p>Циљ истраживања је био да се утврди појава и преваленца паразита Marteilia<br />refringens у медитеранској дагњи (Mytilus galloprovincialis) гајеној у<br />Бококоторском заливу. Осим тога имали смо за циљ да утврдимо да ли<br />еколошки фактори (температура морске воде, салинитет, концентрација<br />кисеоника, pH вредност) и присуство бактерија (Escherichia coli и стрептококи<br />фекалног порекла) утичу на појаву овог паразита у медитеранској дагњи.<br />Вршили смо испитивања на шест различитих локација &ndash; узгајалишта<br />медитеранске дагње у Бококоторском заливу. Укупно је узорковано 960 јединки<br />медитеранске дагње. Marteilia refringens је утврђена на четири локације -<br />узгајалишта. Укупна преваленца паразита Marteilia refringens је износила<br />1,25%. Кретала се од 0% на две локације, 0,56% на једној, 1,67% на једној<br />локацији до максимално 3,33% на двe локације. Пратили смо евентуалну<br />појаву паразита током дванаестомесечног периода, а утврдили смо његово<br />присуство од септембра до децембра и у марту месецу. Од праћених<br />еколошких фактора утврдили смо да највећи утицај на појаву паразита има pH<br />вредност морске воде, с тим што се Marteilia refringens појављује при нижој pH<br />вредности од просечне. Утврдили смо и утицај концентрације кисеоника у<br />морској води, при чему се Marteilia refringens јављала при вишим<br />концентрацијама кисеоника. Нисмо утврдили утицај температуре на појаву<br />паразита, али смо забележили појаву паразита при минималној температури<br />од 11,2˚C. Нисмо статистички доказали утицај салинитета и појаве бактерија у<br />морској води на појаву Marteiliae refringens. Доказали смо негативан утицај<br />појаве паразита Marteilia refringens на индекс кондиције медитеранске дагње.<br />Све мартелије утврђене цитолошким и хистолошким испитивањима смо<br />потврдили и молекуларним испитивањима, при чему смо утвдили да наши<br />изолати паразита припадају М типу Marteiliae refringens. Сви н</p> / <p>Cilj istraživanja je bio da se utvrdi pojava i prevalenca parazita Marteilia<br />refringens u mediteranskoj dagnji (Mytilus galloprovincialis) gajenoj u<br />Bokokotorskom zalivu. Osim toga imali smo za cilj da utvrdimo da li<br />ekološki faktori (temperatura morske vode, salinitet, koncentracija<br />kiseonika, pH vrednost) i prisustvo bakterija (Escherichia coli i streptokoki<br />fekalnog porekla) utiču na pojavu ovog parazita u mediteranskoj dagnji.<br />Vršili smo ispitivanja na šest različitih lokacija &ndash; uzgajališta<br />mediteranske dagnje u Bokokotorskom zalivu. Ukupno je uzorkovano 960 jedinki<br />mediteranske dagnje. Marteilia refringens je utvrđena na četiri lokacije -<br />uzgajališta. Ukupna prevalenca parazita Marteilia refringens je iznosila<br />1,25%. Kretala se od 0% na dve lokacije, 0,56% na jednoj, 1,67% na jednoj<br />lokaciji do maksimalno 3,33% na dve lokacije. Pratili smo eventualnu<br />pojavu parazita tokom dvanaestomesečnog perioda, a utvrdili smo njegovo<br />prisustvo od septembra do decembra i u martu mesecu. Od praćenih<br />ekoloških faktora utvrdili smo da najveći uticaj na pojavu parazita ima pH<br />vrednost morske vode, s tim što se Marteilia refringens pojavljuje pri nižoj pH<br />vrednosti od prosečne. Utvrdili smo i uticaj koncentracije kiseonika u<br />morskoj vodi, pri čemu se Marteilia refringens javljala pri višim<br />koncentracijama kiseonika. Nismo utvrdili uticaj temperature na pojavu<br />parazita, ali smo zabeležili pojavu parazita pri minimalnoj temperaturi<br />od 11,2˚C. Nismo statistički dokazali uticaj saliniteta i pojave bakterija u<br />morskoj vodi na pojavu Marteiliae refringens. Dokazali smo negativan uticaj<br />pojave parazita Marteilia refringens na indeks kondicije mediteranske dagnje.<br />Sve martelije utvrđene citološkim i histološkim ispitivanjima smo<br />potvrdili i molekularnim ispitivanjima, pri čemu smo utvdili da naši<br />izolati parazita pripadaju M tipu Marteiliae refringens. Svi n</p> / <p>The aim of the research was to determine the presence and prevalence of the<br />parasite Marteilia refringens in Mediterranean mussels (Mytilus galloprovincialis)<br />cultivated in Boka kotorska Bay. In addition we aimed to determine wheather<br />environmental factors (temperature of seawater, salinity, oxygen concentration, pH<br />value) and the presence of bacteria (Escherichia coli and streptococci of faecal<br />origin) have influence on the occurrence of this parasite in the Mediterranean<br />mussels. We conducted tests at six different locations. In total 960 individuals of<br />Mediterranean mussels were sampled and included in the study. Marteilia refringens<br />was found at four locations. The overall prevalence of the parasite Marteilia<br />refringens was 1.25%. It ranged from 0% at two locations, 0,56% at one, 1.67% at<br />one to 3,33% at two locations. We traced the possible occurrence of the parasite<br />during a twelve month period, and we found its presence from September till<br />December and in March. We found that the pH value of seawater had the greatest<br />impact on the occurence of the parasite from all monitored environmental factors.<br />Marteilia refringens occurs at lower pH values than the average measured pH<br />values of seawater. We also found that Marteilia refringens occured at the higher<br />concentrations of oxygen in the seawater. We did not determine the effect of<br />temperature on the occurrence of the parasite, but we recorded the occurrence of<br />this parasite at a minimum temperature of 11,2˚C. We did not prove that salinity and<br />the presents of bacteria had an influence on the occurrence of Marteilia refringens.<br />We determined a negative impact of Marteilia refringens on the condition index of<br />Mediterranean mussel. All parasites, determined by cytologic and histologic<br />examination were confirmed by molecular methods. We determined that all our<br />isolates belonged to the M type of Marteilia refringens. All our isolates show genetic<br />uniformity, but also show genetic similarity with other isolates of Marteilia</p>

Made available in DSpace on 2015-05-14T12:09:47Z (GMT). No. of bitstreams: 1 parte1.pdf: 2249022 bytes, checksum: be72d3964d249a323a81467d9135f2b5 (MD5) Previous issue date: 2010-12-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The issue of solid waste management has been a constant theme in discussions of various segments of the society organized, seen the impacts of this question in different sides, be it in the environmental issue, be it in the impact on public accounts, be it by the business that represents for private or, also, as a means of survival for a part of urban populations. In this context, this work was developed with the scope of checking the suitability of using the methodology called Waste Management Condition Index - ICGR for municipalities of Paraíba state, this index was established by indicators that gather in three items: characteristics of system, system planning and operational conditions. In the context of the new National Policy of Solid Waste, recently approved by the Brazilian National Congress, it was emphasized aspects related to integrated solid waste management, reverse logistics, the outlays related the actions of solid waste management, among other aspects addressed in the survey effected in 33 municipalities of Paraíba distributed in its four mesoregions. It was found among the many indicators that the weakest points were the instruments of policy, followed by programs and the final disposal of waste. Regarding the issue of costing of services related to solid waste management in the totality of municipalities surveyed are conducted with funds from the municipal treasury and with the participation of the federal government, whereas may not exist the charge to cover the costs of collection and final disposal of waste by municipalities. / A questão da gestão de resíduos sólidos tem sido uma constante nas discussões dos diversos segmentos da sociedade organizada visto os impactos que esta causa em diferentes vertentes, seja na questão ambiental, seja pelo impacto nas contas públicas, seja pelo negócio que representa para a iniciativa privada ou ainda como meio de sobrevivência para parte das populações urbanas. Neste contexto este trabalho foi desenvolvido com o escopo de verificar a adequabilidade da utilização da metodologia denominada de Índice de Condição da Gestão de Resíduos ICGR para municípios do Estado da Paraíba, tal índice foi estabelecido por indicadores que se congregam em três itens: características do sistema, planejamento do sistema e condições operacionais. No bojo da nova Politica Nacional de Resíduos Sólidos, recentemente aprovada pelo Congresso Nacional Brasileiro, ressaltou-se aspectos ligados a gestão integrada dos resíduos sólidos, a logistica reversa, aos dispendios inerentes as ações de manejo dos resíduos sólidos, entre outros aspectos abordados na pesquisa efetivada em 33 municípios paraibanos distribuidos nas suas quatro mesoregiões. Verificou-se dentre os diversos indicadores que os pontos mais frágeis foram os instrumentos de política, seguidos dos programas e da disposição final dos resíduos. Com relação à questão de custeio dos serviços relacionados à gestão dos resíduos sólidos na totalidade dos municípios pesquisados são realizados com recursos do erário municipal e com a participação do governo federal, visto que inexiste a cobrança de taxa para cobertura das despesas com coleta e destinação final dos resíduos pelos municípios.

Für gemischtkörnige Böden existieren momentan keine eigenen Klassifikationskennwerte zur Beschreibung des Zustands. Die Verfahren zur Zustandsbeschreibung fein- bzw. grobkörniger Böden sind dafür nicht uneingeschränkt nutzbar. Die vorgelegte Arbeit stellt als Lösung ein Konzept für eine allgemeingül-tige Zustandsbeschreibung von Böden auf Basis eines neu entwickelten Bodenzustandsindex vor. Grundlage dafür ist die Aufteilung der Korngrößen des gemischtkörnigen Bodens in Grob- und Feinkorn. Entsprechend der Anteile wird unterschieden in vom Grob- oder vom Feinkorn dominierte Bereiche. Die Abgrenzung erfolgt über einen neuen Kennwert, den Grenzfeinkornanteil. Der eingeführte Bodenzustandsindex ermöglicht zum einen die Quantifizierung des Zustands in Anlehnung an Lagerungsdichte und Konsistenz, und zum anderen wird eine einheitliche sprachliche Zuordnung von Bereichen der Festigkeit vorgeschlagen. Mit diesen Grundlagen wurden Verfahren zur näherungsweisen Angabe von bodenmechanischen Kennwerten der Verdichtung, Zusammendrückbarkeit, Scherfestigkeit und Wasserdurchlässigkeit gemischtkörniger Böden entwickelt. Die abgeleiteten Näherungsverfahren ermöglichen sowohl die Abschätzung der Kennwerte in Abhängigkeit vom Feinkornanteil als auch in Abhängigkeit vom Zustand. Die Qualität der entwickelten Näherungen wird durch die Überprüfung mit eigenen experimentellen Daten und publizierten Ergebnissen aufgezeigt.:1 Einführung - Gegenstand der Arbeit 2 Bautechnische Relevanz gemischtkörniger Böden 3 Klassifizierung und Grenzen der Zustandsbeschreibung 4 Näherungsverfahren für fein- und grobkörnige Böden 5 Allgemeines Konzept zustandsabhängiger Kennwerte gemischtkörniger Böden 6 Modellvalidierung anhand eigener und publizierter Versuchsergebnisse 7 Zusammenfassung und Ausblick

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Previous studies show that pavement condition properties are significant factors to enhance road safety and riding experience, and pavements with low quality might have inadequate performance in terms of safety and riding experience. Pavement Management System (PMS) databases include pavement properties for each segment of the road collected by the agencies. Understanding the impact of road characteristics on crash frequency is a key step to prevent crashes. Whereas other studies analyzed the effect of different characteristics such as International Roughness Index (IRI), Rutting Depth (RD), Annual Average Daily Traffic (AADT), this thesis analyzed the effect of Critical Condition Index (CCI) on crash frequency, in addition to the other factors identified in previous studies. Other characteristics such as Percentage of Heavy Vehicles, Road Surface Condition, Road Lighting Condition, and Driver Conditions are taken into the consideration. The scope of the study is the interstate highway system in Fairfax County, Virginia. Negative Binomial, Least Square and Nominal Logistic Models were developed, showing that the CCI value is a significant factor to predict the number of crashes, and that it has different effect for different values of AADT. The result of this study is a substantial step towards developing an integrated transportation control and infrastructure management framework. / Master of Science / Many factors cause crashes in the roads. Although there is a common sense that road characteristics such as asphalt quality are important in terms of road safety, there are few studies that scientifically prove that statement. In addition, asphalt maintenance decisions making process is mainly based on cost benefit optimization, and traffic safety is not considered at the process. The purpose of this study is to analyze crashes and road characteristics related to each crash to understand the effect of those characteristics on crash frequency, and eventually, to build a model to predict the number of crashes at each part of the road. The model can help transportation agencies to have a better understanding in terms of safety consequences of their infrastructure management plans. The scope of this study is the highway interstate system in Northern Virginia. Results suggest that pavement condition has a significant impact on crash frequency.

Rail is a very expensive component of the railway track. Therefore, research methods extending rail life have great economic importance. During the past thirty years and, particularly during the past ten years there has been an increasing awareness throughout most rail networks in the world of the need to introduce improved design criteria, better construction techniques and higher standard track generally. This implies that quality control at all levels is mandatory if these objectives are to be achieved. With the improved understanding of degradation of track, a more complete comprehension of the costs associated with different operating and infrastructure conditions should also be developed, aiding in the determination of efficient maintenance costs and their contribution to access charges. Track and structures together account for 60% of maintenance costs, with 50% of the total being track. The UIC has done a lot of work on comparative performance indicators, and these show what potential savings much be out there for the taking, just by adopting current best practice. The old wisdom is that it's not enough o do things rights; we have to make sure that we do the right things. These developments have largely resulted from the demand for higher speeds particularly in passenger services and the demand to accept heavier axle loads of freight traffic. Whilst the conventional railway track structure is not likely to change significantly over the next ten years there will be a requirement over that period for better quality track infrastructure. This means less rail surface defects, less internal defects and less wheels irregularities. The presence of rail surface defects generally increases the roughness of the track leading to a poor passenger ride and increased safety risk with freight traffic. In addition, rail surface defects will generally increase the degradation rate of other track components; however, not all defects will produce visible track deterioration. Dynamic impacts produced by the rollingstock running over rail surface defects, such as poor welds, will, over time, create continuous rail defects, loosening of fastenings, abrasion and skewing of sleepers, crushing of ballast and loss of formation geometry. It is only in the recent years that the importance of poor welds in track has been identified. Dips and peaks must be recognised as a severe track irregularity that needs to be addressed and removed. Current maintenance activities have little effect on removing misaligned welds in track and the improvement obtained after the maintenance works is generally short lived. On the other hand, straightening operations have proven to solve the problem and maintain the results following 7 months of traffic. As part of this project, a six kilometre test section was selected on the Mt Isa Line and all welds located in this region were monitored for over 9 months to increase the understanding of the effect of individual maintenance activities on the track roughness. Three 2km Divisions were established; each Division had different maintenance activities and levels of intervention completed over the duration of the project. Over 15,000 readings were recorded and analysed. The following conclusions were drawn. The effect of cycle tamping was clearly identified when comparing the means of weld located in Division 1, 2 to the mean of welds in Division 3. Cycle tamping showed to have a significant positive effect on the dipped welds geometry and an increase in severity of peaked welds prior to their correction. Straightening operations completed in Division 1 and 2 reduced the overall mean of weld misalignments. These Divisions were subjected to different levels of straightening intervention however they produced similar results. Division 1 all dips were straightened and Division 2 only dips &gt0.3mm were straightened. This means that no additional benefit, in terms of overall misalignment of welds, can be gained when straightening operations target dips with a misalignment smaller than 0.3mm. Cycle grinding proved to have little effect on the removal of both dips and peaks. In fact, due to the configuration of the grinding machine, grinding operation produced a slight worsening of the dips misalignments and only a minor improvement of peaks. Although long term monitoring of the site may show minor variations in weld geometry performance, after approximately 3.9 Mgt of traffic the mean of dipped welds in Division 1 and 2 appeared to remain unaltered, as Division 3 showed a minor worsening. Furthermore, the mean of peaked welds in Division 1 and 2 appeared to remain unaltered, as Division 3 showed a minor worsening.

Le parasitisme est de plus en plus considéré comme un facteur écologique pouvant créer des variations dans le comportement des individus. Toutefois, la direction de causalité entre le comportement et le parasitisme reste incertaine. Les infections expérimentales sont le plus souvent réalisées en laboratoire, limitant les inférences écologiques. À l’aide d’une infection expérimentale semi-naturelle, nous avons infecté avec succès des crapets-soleils (Lepomis gibbosus) dans un lac où ils ont été exposés à une variété de vers parasites (trématodes, cestodes), permettant d’examiner les effets de la co-infection naturelle chez les hôtes. Nous avons mesuré la témérité, l’exploration et l’activité avant et après l’infection expérimentale. En utilisant une approche bayésienne, nous avons trouvé que les traits de comportement initiaux exercent une forte influence sur la susceptibilité à l’infection : les poissons les plus téméraires et/ou les moins actifs au départ ont acquis une plus grande densité de points noirs (c.-à-d. points noirs visibles sous la peau, les nageoires et dans les muscles du poisson) et de cestodes lors de l’infection. Par ailleurs, nous avons montré que la condition corporelle est réduite par la densité de cestodes, suggérant la débilitation de l’hôte. La condition corporelle était corrélée positivement avec la distance parcourue, quel que soit le statut d’infection individuel. Nous avons également trouvé une relation négative entre la distance parcourue après l’infection et la densité de trématodes, suggérant que l’infection causant la maladie des points noirs diminue le niveau d’activité des hôtes. La témérité et l'exploration n'étaient pas affectées par la densité parasitaire ou la condition corporelle. Nous suggérons que la diminution de l’activité est causée par une réponse adaptative de l’hôte, visant à rediriger son énergie pour combattre l’infection. Sachant que les points noirs ont un cycle de vie complexe et que le crapet-soleil est un hôte intermédiaire, ce changement dans le comportement de l’hôte pourrait aider le parasite à compléter sa transmission aux oiseaux-hôtes piscivores en augmentant la prédation sur les poissons infectés. Bien que nous ne puissions confirmer la direction de causalité, nos résultats montrent qu’il existe un lien étroit entre le comportement et le parasitisme. Nous suggérons que deux mécanismes peuvent simultanément agir : le comportement initial des individus influence le risque d’infection, et l’infection peut créer de la variation au niveau de la plasticité comportementale des individus. / Parasitism is increasingly seen as an ecological factor that can create variations in individual behaviour. However, the direction of causality between behaviour and parasitism remains uncertain. Experimental infections are most often conducted in laboratories, limiting ecological inferences. Using a semi-natural experimental infection, we successfully infected pumpkinseed sunfish (Lepomis gibbosus) in a lake where they were exposed to various parasitic worms (trematodes, cestodes), allowing us to examine the effects of natural co-infection in hosts. We measured boldness, exploration, and activity before and after the experimental infection. Using a Bayesian approach, we found that initial behavioural traits strongly influence infection susceptibility: initially bolder and/or less active fish acquired a higher density of black spots (i.e., visible black spots under the skin, fins, and in the fish's muscles) and cestodes during the infection. Additionally, we found that body condition was reduced by cestode density, suggesting host debilitation. Body condition was positively correlated with distance swam, regardless of individual infection status. We also found a negative relationship between distance swam after infection and trematode density, suggesting that infection causing black spot disease decreases host activity levels. Boldness and exploration were not affected by parasite density or body condition. We suggest that a decrease in activity is caused by an adaptive host response to redirect its energy to combat the infection. However, since trematode parasites have a complex life cycle and pumpkinseed sunfish are intermediate hosts, decreases in activity levels following infection may make infected fish more susceptible to predation by piscivorous birds, which is needed for trematodes to complete their life cycles. While we cannot confirm the direction of causality, our results show a close link between behaviour and parasitism. We propose that two mechanisms may simultaneously operate: the initial behaviour of individuals influences their risk of infection, and infection can create variation in behavioural plasticity of individuals.