Rework has been a primary cause of cost and schedule overruns in the construction of heavy industrial projects such as those related to oil and gas. It has been reported that the direct cost of rework is about 5% of total construction costs. Several research studies have analyzed the causes and effects of rework in construction projects, but almost no research exists to support decisions with respect of an effective strategy for mitigating the effects of rework on the cost and schedule of the project. This research introduces a new schedule analysis mechanism that considers the impact of rework on project delays and then optimises corrective actions for mitigating those delays. The proposed mechanism considers rework from three perspectives: (1) a schedule representation of the magnitude of rework as a negative percentage completed with respect to the activities affected, as documented on a specific schedule date, (2) a day-by-day delay analysis for quantifying and apportioning project delays among the parties responsible, and (3) an optimization mechanism for determining the best mitigation strategy for recovering rework at a minimum additional cost. The proposed mechanism can represent and mitigate rework caused by both the Owner and the Contractor. The proposed schedule analysis mechanism has been applied to a case study in order to demonstrate its usefulness and applicability. The resulting mechanism offers a quantitative approach to the consideration of rework in delay analysis and the optimization of corrective action, which are important aspects of effective project control.

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As more and more people conduct vigilance-based activities at times other than the traditional daytime work hours, the time utilization will continue to escalate in the next century and will further increase the risks of sleepiness-related accidents. This project, which is commissioned by Scania CV AB, is to nvestigate the potential of a method for sleepiness detection belonging to esium AB. Our objective is to examine whether Scania CV AB should continue with the investigation of the patent method, and in that case, which patent parameters, that indicate sleepiness, should be more closely inquired. The purpose with the method of patent is to discover a sleepy driving behaviour. This method is based on the interaction that appears between the driver and the vehicle. The interaction consists of small spontaneous corrections with the steering wheel that in this report is called micro communication. How well the interaction is functioning can be measured in degree of interaction, which shows how well the driver and the truck interact with each other. The interaction between the driver and the vehicle is in this report looked upon as answers and questions with a certain reaction time, which appears with a certain answered question frequency. The differences in the signal’s amplitudes are measured in variation in amplitudes. Experiments to collect relevant signals have to be conducted in order to investigate the potential with the method of the patent. It is eligible to collect data from a person falling asleep, which implies experiments conducted in a simulator. The experiments are executed in a simulator, one test when they are alert and one when they are sleep deprived. Tests are also executed in a Scania truck. The purpose with these experiments is to collect data of the subject’s normal driving pattern in a truck and to investigate if it is possible to obtain acceptable data in a truck. The sleepiness experiments have indicated that the micro communication takes place in a frequency range of 0.25 to 6.0 Hz. The variables that have been found to detect sleepiness with high reliability are the reaction time and the degree of interaction presented in spectra. The validation experiments have shown it is possible to collect exact and accurate data from the lateral acceleration and the steering wheel torque. But, there is more noise in the signals from truck then there is in the signals from the simulator. This method for sleepiness detection has, according to the authors, a great potential. However, more experiments have to be conducted. The authors suggest further sleepiness experiments only conducted during night time. The subjects are sufficiently alert in the beginning of the test to receive data from normal driving behaviour. Physiological measurement could be interesting to have by the side of the subjective assessments as an additional base for comparison.

The task has been to develop a network media renderer on an embedded linux system running on a Spartan 6 FPGA. One of the challenges have been to make the best use of the limited FPGA area. MP3 have been the prioritised format. To achieve fast MP3 decoding a MicroBlaze soft processor have been configured for speed with concern to the small area availabe. Also the software MP3 decoding process have been accelerated with hardware. MP3 files with full quality (320 kbit/s) can be decoded with real time requirements. A sound interface hardware have been designed to handle the decoded sound samples and convert them to the S/PDIF standard interface. Also UPnP commands have been implemented with the MP3 player software to complete the renderer’s network functionality.

Saab Aerosystems has a long tradition and a lot of competence in the field of flight simulation. Their ambition to broaden the market horizon has led to a discussion about also selling vehicle simulation solutions, both for military and civilian use. The aim of this thesis is to investigate the driver’s experiences of the accelerations he or she is exposed to whilst driving in rough terrain. The results may be used as a basis for future decisions and can act as a platform for the construction of an effective simulation model. To investigate the driver’s exposure of acceleration, some kind of dynamic simulation is needed. A terrain track with both small and large obstacles where constructed. A model of a military vehicle and a civil truck where also constructed with consideration given to the original vehicles’ features. The simulation of the ride along the track was then initiated, which resulted in plots for several parameters, such as acceleration and angular acceleration for the driver relative to the track. The work was focused on the vital properties of the vehicle, such as vehicle length, position of mass centre and wheel size. The simulations led to some conclusions concerning vehicle properties. Boogie type suspension and lever arm type suspension, vertical distance to mass centre, driver’s position, vehicle length, spring and damper for the cab and number of wheels all turned out to be vital constituents to the driver’s experience. On the other hand, properties such as coefficient of restitution and wheel size turned out to have no significant impact. One more conclusion of the work is that CAD software works well for dynamic simulations such as the ones described in this report. It was also apparent that a quite realistic simulation could be achieved with a fairly simple vehicle model. Furthermore, it is essential to get certain parameters such as the vehicle’s length and other major construction differences realistic, otherwise all fine tuning of the vehicle model will be pointless. / Saab Aerosystems har en lång tradition och stor kompetens inom flygsimulering. Strävan efter ett större marknadsområde har gjort att Saab även börjat undersöka möjligheterna att sälja tjänster inom fordonssimulering för både civilt och militärt bruk. Examensarbetet syftar till att undersöka en fordonsförares upplevelser av de accelerationer som förekommer under körning i terräng. Resultatet är tänkt att användas som beslutsunderlag och grund för att bygga upp en effektiv simuleringsmodell för bl.a. terränggående fordon. För att undersöka accelerationerna som föraren utsätts för krävs någon form av dynamiksimulering. För ändamålet har CAD-programvaran Pro Engineer Wildfire valts. En terrängbana i form av små och stora hinder samt två fordonstyper, ett stridsfordon och en lastbil konstruerades, med verkliga förebilder som utgångspunkt. Simuleringar av fordonets färd längs terrängbanan genomfördes. Varje försök genererade grafer för en mängd olika mätvärden, såsom accelerationer och vinkelaccelerationer för föraren relativt banan. Fokus har legat på att undersöka centrala egenskaper hos fordonet såsom längd, masscentrums läge, däckstorlek m.m. och hur dessa påverkar förarens upplevelse. Efter utförda simuleringar stod det klart att de egenskaper hos fordonet som är vitala för förarens upplevelser är boogie- och länkarmsupphängning av hjul, masscentrums läge, förarens position, fordonets axelavstånd, hyttens dämpning och fjädring samt hjulantal. Mindre relevanta för förarens upplevelse är egenskaper såsom stöttal mellan däck och mark samt däckdiameter. Av arbetet framgick även att ett CAD-verktyg med dynamikmodul fungerar mycket väl för dynamiksimuleringar av den karaktär som behandlas i examensarbetet. Det går även att konstatera att relativt verklighetsnära fordonsbeteende går att åstadkomma utan speciellt detaljerad modell av fordonet. Det framgick också att det är av stor vikt att se till att övergripande parametrar såsom fordonets längd och principiella konstruktion överensstämmer med verkligheten. Stämmer inte detta blir alla finjusteringar av fordonsmodellen överflödiga.

Accurate measurements from sensors measuring the vehicle's lateral behavior are vital in todays vehicle dynamic control systems such as the Electronic Stability Program (ESP). This thesis concerns accurate plausibilisation of two of these sensors, namely the yaw rate sensor and the lateral acceleration sensor. The estimation is based on Kalman filtering and culminates in the use of a 2 degree-of-freedom nonlinear two-track model describing the vehicle lateral dynamics. The unknown and time-varying cornering stiffnesses are adapted while the unknown yaw moment of inertia is estimated. The Kalman filter transforms the measured signals into a sequence of residuals that are then investigated with the aid of various change detection methods such as the CuSum algorithm. An investigation into the area of adaptive thresholding has also been made. The change detection methods investigated successfully detects faults in both the yaw rate and the lateral acceleration sensor. It it also shown that adaptive thresholding can be used to improve the diagnosis system. All of the results have been evaluated on-line in a prototype vehicle with real-time fault injection.

Advances in configurable logic technology have permitted the development of low-cost, high-speed configurable devices, allowing one or more soft processor cores to be introduced into a configurable computing system. Soft processor cores offer logic-area savings and reduced configuration times when compared to the hardware-only implementations typically used for application specific acceleration. Programs for a soft processor core are small and simple compared to the design of a hardware core, but can leverage custom hardware within the processor core to provide greater acceleration for specific applications. This thesis presents several configurable system models, and implements one such model on a Nios Embedded Processor Development Board. A software programmable and hardware configurable lightweight processor core known as the FAST CPU is introduced. The configurable system implementation attaches several FAST CPUs to a standard Nios processor to create a system for experimentation with application specific acceleration. This system incorporating the FAST CPUs was tested for bus utilization behaviour, computing performance, and execution times for a minheap application. Experimental results are compared to the performance of a software-only solution, and also with previous research results. Experimental results verify that the theory and models used to predict bus utilization are correct. Performance testing shows that the FAST CPU is approximately 25% slower than a general purpose processor, which is expected. The FAST CPU, however, is 31% smaller in terms of logic area than the general purpose processor, and is 8% smaller than the design of a hardware-only implementation of a minheap for application specific acceleration. The results verify that it is possible to move functionality from a general purpose processor to a lightweight processor, and further, to realize an increase in performance when a task is parallelized across multiple FAST CPUs. The experimentation uses a procedure by which a set of equations can be derived for predicting bus utilization and deriving a cost-benefit curve for a coprocessing entity. They are applied to a specific system in this research, but the methods are generalizable to any coprocessing entity.

Rework has been a primary cause of cost and schedule overruns in the construction of heavy industrial projects such as those related to oil and gas. It has been reported that the direct cost of rework is about 5% of total construction costs. Several research studies have analyzed the causes and effects of rework in construction projects, but almost no research exists to support decisions with respect of an effective strategy for mitigating the effects of rework on the cost and schedule of the project. This research introduces a new schedule analysis mechanism that considers the impact of rework on project delays and then optimises corrective actions for mitigating those delays. The proposed mechanism considers rework from three perspectives: (1) a schedule representation of the magnitude of rework as a negative percentage completed with respect to the activities affected, as documented on a specific schedule date, (2) a day-by-day delay analysis for quantifying and apportioning project delays among the parties responsible, and (3) an optimization mechanism for determining the best mitigation strategy for recovering rework at a minimum additional cost. The proposed mechanism can represent and mitigate rework caused by both the Owner and the Contractor. The proposed schedule analysis mechanism has been applied to a case study in order to demonstrate its usefulness and applicability. The resulting mechanism offers a quantitative approach to the consideration of rework in delay analysis and the optimization of corrective action, which are important aspects of effective project control.

This thesis describes an investigation of the velocity field in a fluid around a solid sphere undergoing transient motion parallel to, and midway between, two plane walls. Particle Image Velocimetry (PIV) was used to measure the velocity at many discrete locations in a plane that was perpendicular to the walls and included the centre of the sphere. The transient motion was achieved by releasing the sphere from rest and allowing it to accelerate to terminal velocity. <p>To avoid complex wake structures, the terminal Reynolds number was kept below 200. Using solutions of glycerol and water, two different fluids were tested. The first fluid was 100%wt glycerol, giving a terminal Reynolds number of 0.6 which represents creeping flow. The second solution was 80%wt glycerol yielding a terminal Reynolds number of 72. For each of these fluids, three wall spacings were examined giving wall spacing to sphere diameter ratios of h/d = 1.2, 1.5 and 6.0. Velocity field measurements were obtained at five locations along the transient in each case. Using Y to denote the distance the sphere has fallen from rest, velocity fields were obtained at Y/d = 0.105, 0.262, 0.524, 1.05, and 3.15. <p>It was observed that the proximity of the walls tends to retard the motion of the sphere. A simple empirical correlation was fit to the observed sphere velocities in each case. A wall correction factor was used on the quasi-steady drag term in order to make the predicted unbounded terminal velocity match the observed terminal velocity when the walls had an effect. While it has been previously established that the velocity of a sphere is retarded by the proximity of walls, the current research examined the link between the motion of the sphere and the dynamics of the fluid that surrounds it. By examining the velocity profile between the surface of the sphere at the equator and the wall, it was noticed that the shear stresses acting on the sphere increase throughout the transient, and also increase as the wall spacing decreases. This is due to the walls blocking the diffusion of vorticity away from the sphere as it accelerates leading to higher shear stresses. <p>In an unbounded fluid, the falling sphere will drag fluid along with it, and further from the sphere, fluid will move upward to compensate. It was found that there is a critical wall spacing that will completely prevent this recirculation in the gap between the sphere and the wall. In the 80%wt glycerol case, this critical wall spacing is between h/d = 1.2 and 1.5, and in the 100%wt glycerol case the critical wall spacing is between h/d = 1.5 and 6.0.

Previous research regarding the relationship between speeding behavior and crashes suggests that drivers who engage in frequent and extreme speeding behavior are over-involved in crashes. However, many of these earlier studies relied on estimates of prevailing and pre-crash speeds, and as a result, their conclusions have been questioned. Over the last several years automotive manufacturers have begun installing airbag systems that collect and maintain accurate pre-crash speeds. Though, patterns of driver speeding behavior are also necessary to discern whether drivers who regularly participate in speeding have increased risk of crash involvement. This dissertation presents a framework and methods for quantifying and analyzing individual driver behavior using instrumented vehicles. The goals of the research were threefold: 1) Develop processing methods and observational coding systems for quantifying driver speeding using instrumented vehicle data; 2) Develop a framework for analyzing aggregate and individual driver speeding behavior; and 3) Explore the potential application of behavioral safety concepts to transportation safety problems. Quantitative assessments of driver speeding behavior could be used in combination with event data recorder data to analyze crash risk. Additionally, speed behavior models could aid in the early identification of problem behavior as well as in the development of targeted countermeasure programs. For this research, 172 instrumented vehicles from the Commute Atlanta program were utilized to collect individual driver speeding behavior. Continuous monitoring capabilities allowed the capture of speed and location for every second of vehicle operation. Driver speeds were then matched to road networks and subsequently to posted speed limits using a geographic information system. This allowed differences between the drivers speed and the posted speed. Several processes were developed to assess the accuracy and the completeness of the data prior to analysis. Finally, metrics and analysis frameworks were tested for their potential usefulness in future behavioral risk analysis. The results of the research were both positive and staggering. On average, nearly 40% of all driving activity by the sample population was above the posted speed limit. The amount and extent of speeding was highest for young drivers. Trends indicate that speeding behavior decreases in amount and extent as age increases.