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Analysis and Comparison of System Performance Using Different Modulation Schemes for Long-Haul Optical Systems and Fiber-To-The-Home Passive Optical NetworksZhu, Xianming 08 1900 (has links)
<p> Analytical expressions for the propagation impairments due to various noise sources in long-haul optical systems and fiber-to-the-home passive optical networks have been obtained. Extensive comparison has been made in this thesis for systems based on different modulation formats, and the advantage of one over the other is clearly stated.</p> <p> For long-haul fiber optical communication systems with inline amplifiers, we have studied the statistical properties of various noise sources in systems based on differential phase-shift keying (DPSK) such as the linear phase noise induced by the amplifier spontaneous emission (ASE) noise, the intra-channel four-wave mixing (IFWM) and the nonlinear phase noise induced by the interplay between ASE noise and fiber Kerr nonlinearity. The error probability of the system based on DPSK is evaluated semi-analytically. In addition, the error probability of the system based on on-off keying (OOK) is calculated taking into account the effects of ASE noise, and the intra-channel nonlinearities such as IFWM and intra-channel cross-phase modulation (IXPM). Comparison of the performance of systems based on DPSK and OOK is made thereafter.</p> <p> For fiber-to-the-home passive optical networks without inline active
photonic devices, different modulation formats have been examined for the downstream and upstream data to enable full-duplex transmission. The statistical properties of Rayleigh backscattering in single-source bi-directional optical systems have been studied including the effects of the high speed external modulation signal and the laser phase noise for systems based on DPSK and OOK. The error probabilities for systems using OOK/OOK topology and DPSK/OOK topology for downstream/upstream transmission have been evaluated and
compared.</p> <p> In addition, the interplay of the amplifier spontaneous emission noise,
fiber nonlinearity and dispersion has been examined starting from the nonlinear Schrödinger equation on the receiver current fluctuation. The variance of the current noise has been evaluated analytically using the two dimensional perturbation theory.</p> / Thesis / Master of Applied Science (MASc)
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LHD operations in sublevel caving mines: a productivity perspectiveTariq, Muhammad January 1900 (has links)
Mining is a high-risk industry, so efficiency and safety are key priorities. As mines continue to go deeper and exploit low-grade deposits, bulk mining methods, such as sublevel caving (SLC), have become increasingly important. SLC is suitable for massive steeply dipping ore bodies and is known for its high degree of mechanisation, productivity, and low operational cost. Moreover, technological developments and mechanisation have allowed these methods to be applied at greater depths. In modern mechanised mines Load haul dump (LHD) machines are central to achieving the desired productivity. Therefore, automation of LHDs and their increasing use in mines make it crucial to understand the performance of these machines in actual mining environments. The aim of this research was to understand the differences in the productivity of semiautonomous and manual LHDs and identify how external factors impact the performance of these machines in SLC operations. The research also investigated how LHD operator training could improve the loading efficiency. Performance data for semi-autonomous and manual LHDs were collected from LKAB’s Kiirunavaara mine’s central database, GIRON. These data were used to compare cycle times and payloads of semi-autonomous and manual LHDs. The data were filtered and sorted so that only data where both machine types were operating in the same area (crosscut, ring, and ore pass) were used. To understand the impact of external factors, data on the occurrence of boulders were collected from LKAB’s Malmberget mine by recording videos of LHD buckets, while the data on operator training were obtained by performing baseline mapping and conducting a questionnaire study with the LHD operators at LKAB’s Kiirunavaara mine. The results of the comparative analysis of manual and semi-autonomous LHDs showed the mean payload was 0.34 tonnes higher for manual LHD machines. However, the differences were not consistent across different areas of the mine. Similarly, when comparing the cycle times, in 57% of the studied area, manual LHDs had lower cycle time, while the opposite was true in the remaining 43% of the areas. Therefore, the differences in cycle time and payload due to mode of operation are not conclusive, meaning that one machine type does not completely outperform the other. This highlights the importance of understanding the external factors that cause such differences. Moreover, the findings emphasize the need to upgrade LHD operator training based on pedagogical principles and the inclusion of new technologies to enhance loading efficiency and increase overall productivity.
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Increasing Haul Truck Safety through the use of Virtual Pre-Shift Inspection TrainingSchaum, Adam Michael 22 June 2007 (has links)
On average, there are approximately ten fatal haul truck accidents per year in the United States. The most common causes for haul truck accidents include mechanical problems, inadequate training, and insufficient road/berm maintenance. Due to the frequency and magnitude of haul truck accidents, new training methods are being investigated. With the widespread availability of inexpensive and powerful computers and newer information technology, the ability to incorporate computer based training for miners is becoming more of a possibility. Computer based training is as effective in knowledge acquisition as traditional lecture, and computer based training can also lead to a significant increase in the retention of material. Studies have also shown that more engaging training methods lead to much more effective knowledge acquisition.
A computer-based virtual environment training system was developed to supplement current new miner training and address the common causes of fatal accidents. The new training system is a virtual pre-shift inspection of a haul truck, and will train the beginner haul truck operator to identify parts which look defective compared to how the parts look normally. The training will increase the operator's ability to recognize problematic parts and correctly identify the corrective action needed. Increasing the quality of training by providing a very engaging simulated hands-on environment will lead to safer behaviors by the trainees, and ultimately fewer accidents and fatalities. / Master of Science
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Detailed Haul Unit Performance ModelPerdomo, Jose Luis 13 September 2001 (has links)
In order to make a profit in any earthmoving operation it is important to plan the operation, select the appropriate equipment and use the haul units efficiently in order to obtain the maximum productivity. Maximizing productivity is one of construction project management personnel's primary objectives, but can also be one of their greatest challenges. The need for effective productivity planning is obvious since productivity ultimately translates into profit. In order to plan an earthmoving operation it is important to understand the travel times of the hauling equipment. Travel time is a variable that, in turn, depends upon other variables associated with the haul unit, and the haul road conditions. Presently there is no travel time model that appropriately considers these factors and simulates the interactions among them such that more detailed analysis could be performed. Such a model needs to be developed. The objective of this research is to develop a detailed model to simulate the travel time considering, in the amount of detail needed, the variables upon which travel time is dependent. The key in the development of the model is the calculation of acceleration. The simulation of how instantaneous acceleration varies may be a complex procedure because instantaneous acceleration is a function of numerous variables, many of which are in turn functions of the velocity and position, which are themselves integral functions of acceleration. The acceleration of a vehicle is dependent on the vehicle characteristics, road conditions, and operator. It is very difficult to consider changes in instantaneous acceleration by using analytical procedures. A numerical method should be used in order to analyze the complex system and determine the travel time or velocity profile of the vehicle. MATLAB software was used to analyze and solve the complex system numerically. A model that considers that the machine is working at full capacity was developed. It considers the variables that affect travel time in the amount of detail needed. The impact that the operator has in the machine performance can be highlighted after a comparison of the results obtained with actual field data, once the model is calibrated. / Master of Science
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Cirkulär masshantering inom infrastrukturprojekt : Potentialen av BIM för cirkularitet / Circular Mass Haul in Infrastructure Projects : The Potential of BIM for CircularityAkkurt, Lukas, Thorbiörnson, Jonathan January 2024 (has links)
I en alltmer globaliserad värld där behovet av transport och kommunikationer ökar, ställs högre krav på infrastrukturprojekt och deras resursanvändning. Kraven på hållbar utveckling påverkar särskilt dessa projekt och deras masshantering. Ett initiativ som adresserar dessa hållbarhetskrav är konceptet cirkularitet där massor cirkuleras inom ett kretslopp i syfte att främja återanvändning och återvinning. Idag möjliggör digitala verktyg såsom Building Information Modeling (BIM) en plattform för aktörer att få en översikt av projektet. Trots detta återstår det utmaningar med att integrera BIM-teknologi inom masshantering för att effektivt främja cirkulär materialanvändning. Studien grundar sig på en explorativ forskningsdesign med syftet att undersöka aktuella utmaningar för cirkulär masshantering samt potentialen hos BIM inom infrastrukturprojekt för att främja cirkularitet. Studien fokuserar på att identifiera de faktorer som aktörer inom masshantering upplever som hinder för cirkulär masshantering samt på vilket sätt BIM kan bidra till att motverka dessa hinder. Studien visar hur dessa uppfattningar relaterar till cirkularitet genom att undersöka hur dessa faktorer påverkar ekonomisk, social och ekologisk hållbarhet i enlighet med Elkingtons Triple Bottom Linemodell. Arbetet grundar sig på en litteraturöversikt och semistrukturerade intervjuer med respondenter i form av beställare, entreprenörer och konsulter verksamma inom svensk masshantering. I studien identifierades att flera faktorer utgör hinder för en cirkulär masshantering inom svenska infrastrukturprojekt. Resultatet tyder på hinder i form av brist på kompetens, otillräcklig samordning, logistikproblem, oklar ansvarsfördelning, svårigheter med klassificering samt inkonsekvent beräkning av massor. Dessa faktorer ger upphov till negativa konsekvenser på de ekonomiska, sociala och ekologiska hållbarhetsaspekterna inom organisationerna. Trots detta betraktar respondenterna att implementeringen av BIM inom masshanteringsprocesserna har potential att motverka dessa hinder genom att främja förbättrad samordning, informationsdelning och resursanvändning. Dessa åtgärder möjliggör förbättringar inom alla tre hållbarhetsdimensioner och kan därmed underlätta övergången mot en mer cirkulär masshantering inom svenska infrastrukturprojekt. Trots detta indikerar resultaten att den fulla potentialen av BIM begränsas av utmaningar såsom bristande erfarenhet och oenhetliganvändning inom branschen. / In an increasingly globalized world where the demand for transportation and communication is rising, higher demands are placed on infrastructure projects and their resource utilization. Sustainable development requirements particularly affect these projects and their mass haul. An initiative addressing these sustainability demands is the concept of circularity, where materials circulate within a loop to promote reuse and recycling. Today, digital tools such as Building Information Modeling (BIM) enable stakeholders to gain an overview of the project. However, challenges remain in integrating BIM technology into mass haul to effectively promote circular material usage. The study is based on an exploratory research design aimed at investigating current challenges in circular material management and the potential of BIM within infrastructure projects to promote circularity. The study focuses on identifying the factors that stakeholders in mass haul perceive as barriers to circular material management and how BIM can help mitigate these barriers. The results illustrate how these perceptions relate to circularity by examining how these factors affect economic, social, and environmental sustainability in accordance with Elkington's Triple Bottom Line model. The report is based on a literature review and semi-structured interviews with respondents such as clients, contractors, and consultants active in Swedish mass haul operations. The study identified several factors that constitute barriers to circular material management in Swedish infrastructure projects. The results suggest barriers such as lack of expertise, inadequate coordination, logistical problems, unclear responsibility allocation, difficulties in classification, and inconsistent calculation of materials. These factors lead to negative consequences on the economic, social, and environmental sustainability aspects within organizations. However, respondents consider that the implementation of BIM within mass haul processes has the potential to counteract these barriers by promoting improved coordination, information sharing, and resource utilization. These measures enable improvements in all three sustainability dimensions and can thus facilitate the transition to a more circular mass haul within Swedish infrastructure projects. Nevertheless, the results indicate that the full potential of BIM is limited by challenges such as lack of experience and inconsistent usage within the industry.
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Education Resource Guide: Jeff Kinney’s ‘The Long Haul’Lyons, Reneé C. 01 January 2017 (has links) (PDF)
This Education Resource Guide includes discussion questions, as well as activities regarding the following three topics related to Diary of a Wimpy Kid: The Long Haul.
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Collision Avoidance Systems for Mine Haul Trucks and Unambiguous Dynamic Real Time Single Object DetectionGlynn, Patrick Joseph, n/a January 2005 (has links)
A suite of new collision avoidance systems (CAS) is presented for use in heavy vehicles whose structure and size necessarily impede driver visibility is introduced. The main goal of the project is to determine the appropriate use of each of the commercially available technologies and, where possible, produce a low cost variant suitable for use in proximity detection on large mining industry haul trucks. CAS variants produced were subjected to a field demonstration and, linked to the output from the earlier CAS 1 project, (a production high-definition in-cabin video monitor and r/f tagging system). The CAS 2 system used low cost Doppler continuous wave radar antennae coupled to the CAS 1 monitor to indicate the presence of an object moving at any speed above 3 Km/h relative to the antennae. The novelty of the CAS 3 system lies in the design of 3 interconnected, modules. The modules are 8 radar antennae (as used in CAS 2) modules located on the truck, software to interface with the end user (i.e. the drivers of the trucks) and a display unit. Modularisation enables the components to be independently tested, evaluated and replaced when in use. The radar antennae modules and the system as a whole are described together with the empirical tests conducted and results obtained. The tests, drawing on Monte-Carlo simulation techniques, demonstrate both the 'correctness' of the implementations and the effectiveness of the system. The results of the testing of the final prototype unit were highly successful both as a computer simulation level and in practical tests on light vehicles. A number of points, (as a consequence of the field test), are reviewed and their application to future projects discussed.
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Truck transport emissions modelCouraud, Amelie 17 September 2007
In the past, transportation related economic analysis has considered agency related costs only. However, transportation managers are moving towards more holistic economic analysis including road user and environmental costs and benefits. In particular, transportation air pollution is causing increasing harm to health and the environment. Transport managers are now considering related emissions in transport economical analyses, and have established strategies to help meet Kyoto Protocol targets, which specified a fifteen percent reduction in Canada's emissions related to 1990 levels within 2008-2012.<p>The objectives of this research are to model heavy vehicle emissions using a emissions computer model which is able to assess various transport applications, and help improve holistic economic transport modeling. Two case studies were evaluated with the model developed.<p>Firstly, the environmental benefits of deploying weigh-in-motion systems at weigh stations to pre-sort heavy vehicles and reduce delays were assessed. The second case study evaluates alternative truck sizes and road upgrades within short heavy oilfield haul in Western Canada. <p>The model developed herein employed a deterministic framework from a sensitivity analysis across independent variables, which identified the most sensitive variables to primary field state conditions. The variables found to be significant included idling time for the weigh-in-motion case study, road stiffness and road grades for the short heavy haul oilfield case study.<p>According to this research, employing WIM at weigh stations would reduce annual Canadian transportation CO<sub>2</sub> emissions by nearly 228 kilo tonnes, or 1.04 percent of the Canadian Kyoto Protocol targets. Regarding direct fuel savings, WIM would save from 90 to 190 million litres of fuel annually, or between $59 and $190 million of direct operating costs.<p>Regarding the short heavy oil haul case study, increasing allowable heavy vehicle sizes while upgrading roads could decrease the annual emissions, the fuel consumption, and their associated costs by an average of 68 percent. Therefore, this could reduce each rural Saskatchewan municipality's annual CO<sub>2</sub> emissions from 13 to 26.7-kilo tonnes, which translates to 0.06 and 0.12 percent of the Canadian Kyoto Protocol targets or between $544,000 and $ 1.1 million annually. <p>Based on these results, the model demonstrates its functionality, and was successfully applied to two typical transportation field state applications. The model generated emissions savings results that appear to be realistic, in terms of potential Kyoto targets, as well as users cost reductions and fuel savings.
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Truck transport emissions modelCouraud, Amelie 17 September 2007 (has links)
In the past, transportation related economic analysis has considered agency related costs only. However, transportation managers are moving towards more holistic economic analysis including road user and environmental costs and benefits. In particular, transportation air pollution is causing increasing harm to health and the environment. Transport managers are now considering related emissions in transport economical analyses, and have established strategies to help meet Kyoto Protocol targets, which specified a fifteen percent reduction in Canada's emissions related to 1990 levels within 2008-2012.<p>The objectives of this research are to model heavy vehicle emissions using a emissions computer model which is able to assess various transport applications, and help improve holistic economic transport modeling. Two case studies were evaluated with the model developed.<p>Firstly, the environmental benefits of deploying weigh-in-motion systems at weigh stations to pre-sort heavy vehicles and reduce delays were assessed. The second case study evaluates alternative truck sizes and road upgrades within short heavy oilfield haul in Western Canada. <p>The model developed herein employed a deterministic framework from a sensitivity analysis across independent variables, which identified the most sensitive variables to primary field state conditions. The variables found to be significant included idling time for the weigh-in-motion case study, road stiffness and road grades for the short heavy haul oilfield case study.<p>According to this research, employing WIM at weigh stations would reduce annual Canadian transportation CO<sub>2</sub> emissions by nearly 228 kilo tonnes, or 1.04 percent of the Canadian Kyoto Protocol targets. Regarding direct fuel savings, WIM would save from 90 to 190 million litres of fuel annually, or between $59 and $190 million of direct operating costs.<p>Regarding the short heavy oil haul case study, increasing allowable heavy vehicle sizes while upgrading roads could decrease the annual emissions, the fuel consumption, and their associated costs by an average of 68 percent. Therefore, this could reduce each rural Saskatchewan municipality's annual CO<sub>2</sub> emissions from 13 to 26.7-kilo tonnes, which translates to 0.06 and 0.12 percent of the Canadian Kyoto Protocol targets or between $544,000 and $ 1.1 million annually. <p>Based on these results, the model demonstrates its functionality, and was successfully applied to two typical transportation field state applications. The model generated emissions savings results that appear to be realistic, in terms of potential Kyoto targets, as well as users cost reductions and fuel savings.
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Modelling road and rail freight energy consumption: A comparative studyParajuli, Ashis January 2005 (has links)
After reviewing land based freight growth trends nationally and internationally, this thesis discusses the main parameters governing fuel consumption, as well as past approaches in modelling road and rail energy consumption. Past work on comparing these two main modes is also reviewed here. The review included ways of estimating energy consumption of a complete freight task i.e., from origin to destination. Mathematical models estimating modal energy consumption are presented in this thesis. Modal energy consumption is a complex function to be approximated in practice due to numerous variables affecting their outcome. Energy demands are particularly sensitive to changes in vehicle characteristics such as mass and size; route parameters such as grade and curvature; traffic conditions such as level of congestion; and less sensitive to ambient conditions, such as temperature and altitude. There is a large set of energy estimation models available to transportation planners. Unfortunately, unless simple relationships are established for energy estimation and modal comparison, their application in freight movement planning and corridor development becomes computationally prohibitive. This thesis describes the development of a modal freight energy comparison tool to quantify the energy advantage from mode choice, corridor development and vehicle types and loading improvements. The thesis also describes the used modelling processes and the trade-offs between model complexity and data quality. The tool developed in this thesis is based on well established relationships between energy consumption and traffic flow, route and vehicle operating characteristics for road freight movement. The rail freight component was developed from equations of motion together with parameters obtained from past studies. The relationships have been enhanced to fit the purpose of corridor level comparative analysis. The comparison tool has been implemented using a spreadsheet based approach developed specifically to calculate the total door to door energy consumption for given task options. A series of linked sheets enable the user to: specify all necessary inputs; estimate road and rail energy by trip segment. The outputs consist of trip segment energy demand and total energy efficiency of each option. A case study approach, for aiding in model development and testing, is presented. Toowoomba second range crossing in Southern Queensland, Australia (section between below Postman's Ridge and Gowrie Junction) was selected. Four options considered include existing and proposed road and rail corridors. The existing rail and road corridors could be taken as a typical poor case, with very high grades and sharp curvatures. The proposed new road section has a relaxed curvature and gradient. The section of proposed rail corridor, under consideration here, still contains a high grade section. However, the proposed track length is considerably shorter than the base-case. The new proposed train alignment was found as the most efficient mode and the existing trains as the least efficient mode when measured based on absolute expected fuel gain (litres/tonnage of freight moved). This could be attributed to the improvement in curvature and load carrying capacity. However, when the options are compared in terms of litres/1000 NTK, the new train option did not show a significant advantage. Furthermore, the developed model was applied on some simulated cases to test the functionality of other aspects of the model. The total door-to-door energy consumption and the efficiency were compared for all the simulated cases. It showed that the energy efficiency of scenarios varies exponentially with the variation in the ratio of road pickup and delivery legs to the rail line-haul length. In general, energy efficiency of the intermodal options was found to be better unless the best case of the road and the worst case of intermodal option was compared. The modelling approaches presented in the thesis and the comparison model developed in this study could be used for several purposes namely: to assess the energy (and hence greenhouse gas) implications of specific modal freight movements; to aid in the economic and environmental evaluation of transport options; and to assess the potential for energy efficiency gains from vehicle and infrastructure improvements. A number of suggested improvements to the model are also discussed.
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