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Method for detection of sleepiness : measurement of interaction between driver and vehicleLundin, Maria, Kanstrup, Lena January 2006 (has links)
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.
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Design and simulation of beam steering for 1D and 2D phased antenna arrays using ADS.Afridi, Muhammad Zeeshan, Umer, Muhammad, Razi, Daniyal January 2012 (has links)
Phased arrays eliminate the problems of mechanical steering by using fast and reliable electronic components for steering the main beam. Modeling and simulation of beam steering for 1D and 2D arrays is the aspect that is considered in this thesis. A 1D array with 4 elements and a 2D array with 16 elements are studied in the X-band (8-12 GHz). The RF front-end of a phased array radar is modeled by means of ADS Momentum (Advanced design system).
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Modelling of Auxiliary Devices for a Hardware-in-the-Loop Application / Modellering av hjälpaggregat för en hardware-in-the-loop-applikationOlsén, Johan January 2005 (has links)
The engine torque is an important control signal. This signal is disturbed by the devices mounted on the belt. To better be able to estimate the torque signal, this work aims to model the auxiliary devices'influence on the crankshaft torque. Physical models have been developed for the air conditioning compressor, the alternator and the power steering pump. If these models are to be used in control unit function development and testing, they have to be fast enough to run on a hardware-in-the-loop simulator in real time. The models have been simplified to meet these demands. The compressor model has a good physical basis, but the validity of the control mechanism is uncertain. The alternator model has been tested against a real electronic control unit in a hardware-in-the-loop simulator, and tests show good results. Validation against measurements is however necessary to confirm the results. The power steering pump model also has a good physical basis, but it is argued that a simple model relating the macro input-output power could be more valuable for control unit function development.
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Steering Behaviour of 44 Drivers in Lane Change Manoeuvres on a Slippery SurfaceRizzi, Matteo January 2005 (has links)
This master thesis deals with experimental data that were collected through a crash avoidance experiment (which was lead by Professor Lennart Strandberg) in February and March 1990. Fifty-two ordinary drivers were instructed to perform two different kinds of manoeuvres on ice to determine the effectiveness of antilock brakes and of four tyre configurations. Results were reported at the 1991 ESV Conference. The first aim of this master thesis is to check and revise the measured data (used by Prof. Strandberg in courses at Linköping University). Checking out many hours of video recordings from onboard cameras reveals various protocol inconsistencies and errors, which in some cases it is not possible to correct. This work might increase the reliability of any further analysis of these data. The second aim is to elaborate on the revised data and to test the hypothesis that quick steering is a key factor to not lose control of the car during a crash avoidance manoeuvre. Different variables are introduced and used to estimate the steering wheel velocity and lateral friction use. The results show linear (positive) correlations between lateral friction use and steering wheel velocity. The greatest steering wheel velocities appear in the tests with loss-of-control and reach values up to 1180 degrees per second. However, the 1990 experimental layout was not intended for this type of research questions and it seems difficult to determine the causal relationship between quick steering and control of the car. Some cases of excessive steering input might have occurred. The results indicate that quick steering by itself is not enough to guarantee the total control of the car. An early reaction to the skid might be necessary too. Evidently, further research is needed.
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”Den svarta pärmen” : En socialpsykologisk studie om styrdokumentens betydelse för sociala relationer på ett företagRobertsson, Monica, Benjaminsson, Evelina January 2012 (has links)
I denna uppsats har vi undersökt hur styrdokumenten inom ett medelstort företag i Västsverige påverkar organisationskulturen och samspelet mellan personalen. Vårt syfte har varit att öka förståelsen kring hur eller om dessa dokument kan styra och påverka individerna och kulturen inom en organisation. Vi har utgått ifrån ett institutionellt etnografiskt och etnometodologiskt angreppssätt i vår ansats in i fältet. Vi har genom detta sett till dokumenten som en makronivå, translokal nivå och samspelet som en mikronivå, lokal nivå inom företaget. Detta angreppsätt har blivit både vår metodologiska utgångspunkt samtidigt som de även blivit en hjälp i vårt analysarbete med det empiriska materialet. För att förstärka vår analys utifrån metoderna har vi även tagit in Randall Collins teori om interaktionsritualer samt Johan Asplunds teori om social responsivitet. Insamlingen av det empiriska materialet gjordes utifrån en triangulering av metoder i form av en mindre observation av arbetsplatsen, intervjuer med personal och ledning samt en textanalys av företagets verksamhetshandbok. Resultatet vi kom fram till i denna studie var att styrdokumenten, organisationskultur och samspelet på arbetsplatsen står i relation till varandra där det finns en svårighet i att uttolka vilket som kom först eller vad som påverkar det andra mest. / In this study we have researched how policy and procedure documents in an organisation influences the culture and the social interaction between the workers. Our goal as been to increase the understanding on how these documents can control and influence the individuals and the culture in an organisation. To help us understand our material we have had institutional ethnography and ethnomethodology in our approach. Our approach has helped us to analyse and view these documents from a macro perspective, as a translokal relation and the social interaction from a micro perspective, a local level within the organisation. These methods have also helped us in our analysis, but in order to confirm and strengthen this we have used both Johan Asplunds theory about social responsivitet and Randall Collins interaction ritual chain. In order to collect the empirical data we did an observation of the workplace, interviewed the employees and a text analysis of the policy and procedure documents. The conclusion of the study was that the policy and procedure documents, the organisational culture and the social interaction between the workers were in a close correlation, thus making it difficult to see which of these factors that had the most influence.
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Design and Implementation of Steering Vehicles System by JoystickLin, Yu-kun 13 July 2011 (has links)
The goal of this thesis is to design the steering vehicle system by joystick. The main function of the steering vehicle system is drivers can operate the joystick with electrical control to accomplish steering motion. In this paper , the main design framework of the steering vehicle system is divided into three stages of the experiment, vehicle architecture, vehicle dynamic simulation and vehicle test results . The overall system is modified Go-kart as a platform, develop a suitable joystick framework in the vehicle, and apply the encoder on the joystick, which transfer the control information into the position signal, to be the input command of steering motor control program. According to the steering by wire for brushless DC servo motor control strategy, the system control architecture achieve the goal by embedded-DSP. And to test double-lane change by Go-kart. Experimental results recorded by gyroscope can compare the steering situation of joystick with steering wheel.
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Model establish and controller design for active front steering control systemHsiao, Chin-yuan 09 August 2012 (has links)
The goal of this thesis is to develop an active front steering(AFS) control system which can apply to ordinary vehicle. This AFS control system stabilizes the driving vehicle and reduces the possibility of rollover. This thesis uses magic formula tire model and constructs a vehicle model with eight degrees of freedom to study the dynamic behavior of the real driving vehicle. This thesis constructs a vehicle model with three degrees of freedom and eight degree of freedom, compare with two vehicle model, we adopt eight vehicle model in this thesis. The advantages of PI controller are low cost and easy to modify, so this thesis adopts PI controller as the control strategy. This study uses four simulate methods and compares the simulated results to develop the AFS control system which can apply to ordinary vehicle.
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Encoding large array signals into a 3D sound field representation for selective listening point audio based on blind source separationNIWA, Kenta, NISHINO, Takanori, 西野, 隆典, TAKEDA, Kazuya 03 1900 (has links)
No description available.
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Frequency steerable acoustic transducersSenesi, Matteo 22 June 2012 (has links)
Structural health monitoring (SHM) is an active research area devoted to the assessment of the structural integrity of critical components of aerospace, civil and mechanical systems. Guided wave methods have been proposed for SHM of plate-like structures using permanently attached piezoelectric transducers, which generate and sense waves to evaluate the presence of damage. Effective interrogation of structural health is often facilitated by sensors and actuators with the ability to perform directional scanning.
In this research, the novel class of Frequency Steerable Acoustic Transducers (FSATs) is proposed for directional generation/sensing of guided waves. The FSATs are characterized by a spatial arrangement of the piezoelectric material which leads to frequency-dependent directionality. The resulting FSATs can be employed both for directional sensing and generation of guided waves, without relying on phasing and control of a large number of channels.
Because there is no need for individual control of transducer elements, hardware and power requirements are drastically reduced so that cost and hardware limitations of traditional phased arrays can be partially overcome. The FSATs can be also good candidates for remote sensing and actuation applications, due to their hardware simplicity and robustness.
Validation of the proposed concepts first employs numerical methods. Next, the prototyping of the FSATs allows an experimental investigation confirming the analytical and numerical predictions. Imaging algorithm based on frequency warping is also proposed to enhance results representation.
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Implementering av centralt fattade beslut i ett regionalt samverkanskomplex : en studie om implementeringen av de sociala hållbarhetsaspekterna i Kronobergs regionala tillväxtprogramEmilsson, Kajsa January 2008 (has links)
<p>Abstract</p><p>The aim of this study is to investigate the implementation process and the implementation steering of the social development aspects, gender equality and integration, in the program for regional development of the region Kronoberg in the period of 2004-2007.</p><p>The study asks three questions: 1) How have the social development aspects, gender equality and integration, been implemented in the program for regional development of the region Kronoberg? 2) What has facilitated or hindered the implementation of the two social development aspects? 3) What possibilities to steer the implementation process of the two social development aspects exist at the governmental and at the regional level?</p><p>In order to answer these questions a qualitative method has been used. To be able to analyse the empirical material, which consists of documents and interviews, the theoretical framework comprehends the policy process and implementation steering. The conclusion is that the incorporation of the social development aspects in the regional development program does not fully correspond with the central intentions, and that is due to circumstances at the regional level.</p>
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