<p>The demands on decreased environmental impact from vehicles force the automotive industry to develop engines with reduced engine oil and fuel consumption. Engine oil consumption is recognized to be a significant source of pollutant emissions. Unburned or partially burned oil in the exhaust gases contribute directly to hydrocarbon and particulate emissions. Engine oil and fuel consumption are to a great extend controlled by the topography of the cylinder liner surface.</p><p>Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing.</p><p>One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, event though the diamond honing process results in higher productivity, improved demands of quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing.</p><p>A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The liners where tested in a reciprocating rig of 8 mm stroke and with a frequency of 10 Hz, simulating the top-dead center conditions in a running engine. </p><p>The tests where carried out in high- and low pressure conditions with smooth respectively rough liner roughnesses against PVD coated piston rings. The developed surface mapping method was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer.</p><p>The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The roughness of the core decreases more for diesel liners than for petrol liners. In average (rough and smooth liners) the diesel core roughness decreases 265% while the petrol liners average on a 60% decrease. Blechmantel- and Irregularities ratio show a high sensitivity to varying conditions and decrease 1180% to 100% for the diesel liners while the parameters increase between 106% to 18% for all the petrol liners. A probable cause is the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions not manage to remove the blechmantel and irregularities in an important extent.</p>

The demands on decreased environmental impact from vehicles force the automotive industry to develop engines with reduced engine oil and fuel consumption. Engine oil consumption is recognized to be a significant source of pollutant emissions. Unburned or partially burned oil in the exhaust gases contribute directly to hydrocarbon and particulate emissions. Engine oil and fuel consumption are to a great extend controlled by the topography of the cylinder liner surface. Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing. One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, event though the diamond honing process results in higher productivity, improved demands of quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing. A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The liners where tested in a reciprocating rig of 8 mm stroke and with a frequency of 10 Hz, simulating the top-dead center conditions in a running engine. The tests where carried out in high- and low pressure conditions with smooth respectively rough liner roughnesses against PVD coated piston rings. The developed surface mapping method was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer. The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The roughness of the core decreases more for diesel liners than for petrol liners. In average (rough and smooth liners) the diesel core roughness decreases 265% while the petrol liners average on a 60% decrease. Blechmantel- and Irregularities ratio show a high sensitivity to varying conditions and decrease 1180% to 100% for the diesel liners while the parameters increase between 106% to 18% for all the petrol liners. A probable cause is the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions not manage to remove the blechmantel and irregularities in an important extent.

Squeezing ground in tunnelling is a unique method of failure, typically occurring in ductile rock at depth. To accommodate this mechanism of failure, liners have been designed such that they reduce in circumference as the support takes on initial load. Technological development in this area is all the more important for tunnels mined in heterogeneous rockmasses. Currently, the state of practice is to design support based on a normalised average of the strength parameters of the rock units present in the tunnel face. Under many configurations of heterogeneity, this approach is perfectly valid, however there are styles and magnitudes of heterogeneity that require deeper analysis. The purpose of this study is to introduce an empirical relationship between liner response in heterogeneous rockmasses and liner response in the homogenised equivalent. A suite of parameters that define heterogeneity were numerically modelled, using finite element analysis, such that a comprehensive set of the various permutations was evaluated. The three styles of heterogeneity that were modelled were chaotic structure, folded structure and laminar structure, these represent common and discrete structures found in alpine regions. Laminar structure was considered at three orientations, and all structures were considered under hydrostatic and differential stress regimes. Granularity, or scale, and contrast ratio of units were also varied. These data were analysed with respect to mean axial thrust, range of axial thrust and range of moment on the liner. Liner response analysis was also conducted on the case study of St. Martin-la-Porte, an adit to the Lyon-Turin Ferroviaire base tunnel in southern France. This adit has been excavated in a highly variable, heterogeneous rockmass and provides realistic examples of the nature of heterogeneity present in current tunnelling projects. Ultimately, three equations were developed to provide preliminary predictions of heterogeneous axial thrust and moment variability from the analysis of homogeneous equivalents. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-01-14 19:16:42.908

Intact geomembranes are barriers to advective aqueous flow and are often a key component in the design of composite bottom liner and cover systems. During installation, the combination of solar heating, a high coefficient of expansion, and the stiffness of high density polyethylene (HDPE) causes the geomembrane to expand and buckle, forming wrinkles (waves). Up to 20 – 30% of the area of the geomembrane may be below hydraulically connected wrinkles, which could substantially increase leakage through the composite liner if there is a hole on or near a wrinkle in the connected network. To quantify wrinkles at the field scale, a technique for low altitude aerial photography and photogrammetric correction was developed. Wrinkles were quantified for nine field cases involving a variety of installation (area, geomembrane thickness and texture, orientation, subgrade) and weather conditions. The technique was used to quantify the geometry of individual wrinkles (length, width and area) and, more importantly, the length of the longest hydraulically connected wrinkle at each time. Hand measurements of height and width were conducted at five of the cases. Air temperature, solar radiation, and geomembrane surface temperature was recorded as permitted by site conditions and instrumentation. The longest measured connected wrinkle was 5330 m on a 0.61 ha slope. For a 1.5-mm-thick geomembrane, the average wrinkle width over a GCL was 0.20-0.23 m and 0.24 – 0.32 m over a CCL. The average hand-measured wrinkle height was 0.06 m, and the tallest wrinkle measured was 0.18 m. The longest connected wrinkle length was <200 m when the sum of the wrinkle lengths was < 580 m (<8% of the area of the geomembrane was wrinkles). The reported connected wrinkle lengths are significantly longer than previously reported values. When used as input into an existing theoretical leakage solution, these very long wrinkles can explain previous large field measurements of leakage. The results also suggest that simply limiting the time of day when cover soil is placed and/or reducing the area in which wrinkles can form may greatly reduce the length of connected wrinkles after covering. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2012-06-29 16:05:18.598

Geosynthetic Clay Liners (GCLs) are commonly paired with a geomembrane and used as part of a composite liner system for landfill barriers. Under some circumstances, leaving a composite geomembrane/geosynthetic clay liner exposed to solar radiation in the field has been shown to cause shrinkage of the underlying GCL. Recent field studies have shown that leaving a composite liner exposed can also lead to down-slope erosion of bentonite from the GCL due to the down-slope movement of moisture. To investigate the factors that can affect the onset of bentonite erosion in a GCL an experimental technique was developed to reproduce similar erosion in the laboratory. The test method simulates the features that occur with the erosion of bentonite caused by down-slope migration of evaporative water in the field. One needle-punched GCL was tested to examine the factors that can affect the onset of erosion of bentonite particles with the flow of water. The factors examined include the effect of the initial wet/dry cycle, water source chemistry, flow rate, slope, prior cation exchange, and the effect of no drying phase in the test cycle. Ten different manufactured GCL products were tested to examine the effect of material properties on the erosion of bentonite from a GCL. The material properties of the products tested differed in terms of the type of carrier and cover geotextiles, bentonite (powdered, fine and coarse grained, and some with a polymer enhancement additive) and the presence of a polypropylene coating over the geotextile. It was found that the most critical factor to trigger the onset of bentonite erosion was the water source chemistry, with the tests that simulated the evaporation and condensation of water (deionized water) below an exposed composite liner leading to the formation of major erosion features. The results of the laboratory testing program also show that erosion features are more visible in products with white coloured geotextiles. The products containing a polypropylene coated geotextile and polymer enhanced bentonite slowed or, in some cases, prevented erosion features from developing. / Thesis (Master, Civil Engineering) -- Queen's University, 2014-05-01 10:16:14.05

Les réservoirs composites de type IV utilisés pour le stockage de l’hydrogène gazeux rencontrent du succès dans les applications mobiles de la pile à combustible. Au cours de leur utilisation, ces supports de stockage sont soumis à des cycles successifs de remplissage/maintien/vidange en hydrogène. Sous des conditions spécifiques de vidange, l’apparition d’un décollement entre l’enveloppe en polyamide 6 qui assure l’étanchéité (liner) et la paroi composite, peut être observée. Ce décollement, encore appelé collapse, peut poser des problèmes de limitation à un débit de vidange lent ou à un seuil minimal de pression résiduelle du gaz sur le liner.Air Liquide a cherché à élucider expérimentalement l’influence des cycles de pression en hydrogène sur le comportement mécanique des liners en situation de collapse. Mais compte tenu des coûts très élevés des essais, l’utilisation d’un outil numérique prédictif s’avérait nécessaire. L’enjeu principal dans le développement d’un tel outil était la modélisation du comportement d’un liner collapsé sous des chargements de cyclage – fluage.L’objectif de cette thèse est de proposer une loi de comportement capable de prédire l’évolution cyclique de la déformée d’un liner en situation collapsée.Le liner est exposé à plusieurs variations de son environnement : présence d’un résidu d’humidité dans le liner après épreuve hydraulique, variations de températures générées par la compression/détente de l’hydrogène, diffusion de l’hydrogène dans le liner. Un travail préliminaire a donc consisté à évaluer l’influence de ces différents facteurs environnementaux sur la réponse mécanique du polyamide 6. Cette première étape a permis de définir un cadre de sollicitation à l’échelle du laboratoire, mais qui préserve les principales caractéristiques du collapse. Les essais de caractérisation sur éprouvette ont montré que le liner pouvait être modélisé par une loi viscoélastique multiaxiale formulée dans le cadre thermodynamique des processus irréversibles en petites déformations, faiblement couplée avec la thermique. Des modifications mineures ont été introduites pour permettre à cette loi de capter les effets du comportement en fatigue-fluage d’un liner en situation collapsé. Ces modifications ont malheureusement pénalisé l’identification manuelle et par conséquent, ont conduit à développer une stratégie d’identification spécifique. La qualité de d’identification a été évaluée dans le cadre isotherme en regardant les effets de la vitesse de la sollicitation, du niveau de contrainte et de la température. Puis, le modèle a été validé en présence de transitoires thermiques, d’abord sur éprouvette, ensuite dans un réservoir en présence d’un collapse. / Hyperbaric hydrogen storage vessels of type IV are encountering success for portable applications of fuel cell. During their use, these cylindric containers undergo repeated fill in/fill out cycles of H2-gaz. Under specific fillout conditions, an emerging detachment between the sealing inner layer (liner) and the composite wall, can be observed. This layer debonding also called collapse may limit the pressure release rate of H2-vessels or increase the residual gas pressure prescribed to avoid collapse.Experimental studies have been conducted by Air Liquide at vessel scale to identify some parameters responsible for the collapse onset. But the high cost of these studies and the complexity of the operating conditions makes the use of numerical tools necessary. That led to a numerical modeling approach. The main goal in the numerical approach is to model the cyclic mechanical response of a collapsed liner under fatigue – creep loadings.In this thesis, the purpose was to develop a mechanical constitutive law able to predict the cyclic deformation of a collapsed liner subjected to hydrogen pressure cycles.The liner was subjected to several environment variations due to: (i) the presence of residual water into the liner after initial hydraulic vessel tests, (ii) the temperature changes caused by the hydrogen compression/expansion, and (iii) the hydrogen diffusion/saturation. So, a preliminary work consisted in investigating the influence of each environmental factor on the polyamide 6 mechanical response. This first step allowed to outline a loading frame at laboratory scale that preserved main characteristics of the collapse phenomenon. Characterization tests on tensile specimens revealed that the liner could be modelled by a non linear viscoelastic law written within the thermodynamic framework of the irreversible processes in small deformations, and coupled with the temperature. Minor changes were introduced to extend the model capacity to capture liner behavior effects during fatigue – creep. These changes had negative impact on the manual method of model calibration, and consequently required to develop a specific identification strategy. The identification performance was assessed in different isothermal frames through stress rate, stress level and temperature effects. Then, the calibrated model was validated by taking temperature gradients into account, firstly on a tensile specimen, secondly within a H2-vessel.

The main scope of this thesis is to select alternative landfill sites for Ankara based on the growing trends of Ankara towards the Sincan and G&ouml / lbaSi municipalities and to eventually select the best alternative. Landfill site selection was carried out utilizing Geographic Information System (GIS) and Multi-Criteria-Decision-Analysis (MCDA). A number of criteria were gathered in a GIS environment. Each criterion was assigned a weight value by applying the Pairwise Comparison Method (PCM). &ldquo / The Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS)&rdquo / , was applied and the best landfill site alternative was determined. The geotechnical properties of the clay samples, obtained from selected locations in G&ouml / lbaSi and Sincan were determined in order to design a landfill liner system using compacted &ldquo / Ankara Clay&rdquo / as the liner material. The permeability values for the clay samples were determined by performing falling head tests and consolidation tests. The coefficient of permeability value of the compacted clay was determined to be in the order of 10-10 m/s for the G&ouml / lbaSi samples and 10-11 m/s for the Sincan samples for both of the tests performed. These tests indicated that the native clay was suitable to be utilized as a landfill liner material. The HELP and POLLUTE was employed for the purpose of landfill design and predicting the landfill hydrological processes. The landfill profile with a double lining system composed of geomembrane/compacted clay composite top and bottom liners with a drainage layer was determined to show the best performance amongst the others.

A lot of relevant literature indicates that stock market returns for the non-linear because the stock market is volatility asymmetry. To explore the impact between the stock and macroeconomic variables, it is necessary to analyze by nonlinear model, otherwise they will be a model set of problems. I adopt a threshold autoregressive modle to analyze the relationship between the ETF return on the exchange rate and economic growth. In this study, the ETF return is the threshold variable. First, in order to rearrange the linear test regression (Arrang Regression) with the F-statistic testing whether the nonlinear effect of the grid search to find the residual sum of squares, determine the optimal threshold of backward and thresholds value. To identify the threshold, it is estimated a two-regime model analysis in positive and negative reward, the correlation between exchange rate and ETF returns Spillover effect to explain economic growth for the ETF returns and how it affects, then the data drawn into a grid map, find the number of possible structural transition point, and finally AIC formula to calculate the value of the two -regime with the three-regime model of AIC and the minimum value is the optimal model.

There are two markable ocean going container liners, Evergreen maritime corporation¡]EMC¡^ and Yang Ming maritime corporation¡]YML¡^, in Taiwan. They are listed in the top20 container liners of the world and operating with good repution in this industry. The Evergreen has launched a global service with both the east and the west bound since 1984, and then it continuously expanded bussiness scale and became the biggest container liner around the world in 1985. At same time, YML created a new service model between the Europe-FarEast-North America by pedulum. Therefore, they are the leaders in the shipping industry. They are also honors to our country. The container has initiated in 1960s. After delveloping for decades, the transportation of the container has become as a maturity industry and been competing violently. There were ten great container liners, Mersk/ P&OCL, NOL/ NYK, K-LINE/ MOL, APL/ OOCL and YML/ HANJIN, forming joint venture in 1991. The main container liners became four big global alliances in 1994. And then they regrouped in 1996 and 1999. These few alliances share most part of the market of the world. The local outstanding liner YML, which just shares 1.7% of the market, organizated a ¡§CKYH¡¨ group with COSCO, K-LINE and HANJIN to enhance competition in 2002. However, the Evergreen still keeps as a main outsider of the alliances. The management models of these two local markable liners, Evergreen and YangMing Line, are different. Evergreen is a private company. Nevertheless, the YangMing Line which used to belong to the government and become privatized in 1996. Anyway, both of them have been operating with competition and performing excellently. What kind of strategies did they use before? What are the strategies they are using now? In this paper the author tried to find the strategies of these two companies and create a model of both development and competition for the shipping industry of the container.

The physical response of composite landfill liners consisting of a geomembrane on top of a geosynthetic clay liner (GCL) are examined under simulated landfill conditions. The deformation and strains of a 1.5-mm-thick high-density polyethylene geomembrane and thickness and hydraulic performance of a nominally 7-mm-thick GCL are quantified when the composite liner was buried beneath 50 mm coarse gravel, at applied pressures up to 1000 kPa, with a firm sand foundation layer, and with and without a wrinkle in the geomembrane. At an applied pressure of 250 kPa, with either no protection or conventional thick nonwoven needle-punched geotextile protection layers, the tensile strains in the geomembrane exceeded a 3% allowable limit and the GCL was reduced in thickness to as little as 2.2 mm from extrusion of bentonite beneath a gravel particle. Whereas a 150-mm-thick sand protection layer limited strains in the geomembrane to 0.1% and prevented extrusion in the GCL so that deformation was from bentonite consolidation and not from extrusion. A GCL with a thickness of less than 3 mm from extrusion was shown to be susceptible to failure from internal erosion of bentonite in the GCL at hydraulic head differences across the GCL between 1-10 m. Conversely with the sand protection layer, the GCL could withstand a head difference of greater than 100 m without any evidence of internal erosion. Further, the permittivity of an extruded 3.5-mm-thick GCL was found to be 4.5 times larger than a 7-mm-thick GCL that did not experience extrusion. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2008-09-05 10:47:21.783