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No description available.

Noise-induced hearing loss (NIHL) is one of the most common illnesses that is frequently reported in the occupational and military sectors. Hearing loss due to high noise exposure is a major health problem with economic consequences. Industrial and military noise exposures often contain high-level impulsive noise components. The presence of these impulsive noise components complicates the assessment of noise levels for hearing conservation purposes. The current noise guidelines use equal energy hypothesis (EEH) based metrics to evaluate the risk of hearing loss. A number of studies show that the current noise metrics often underestimates the risk of hearing loss in high-level complex noise environments. The overarching goal of this dissertation is to develop advance signal processing based methods for more accurate assessments of the risk of NIHL. For these assessments, various auditory filters that take into account the physiological characteristics of the ear are used. These filters will help to understand the complexity of the ear’s response to high-level complex noises.

Many city planners, regional authorities and transport providers are tasked with the challenging job of selecting which type of public buses are suited to their location and priorities. The challenges of which are multidimensional in nature due to different policies to adhere to as well as economic, environmental and technical tradeoffs between options. The aim of this report was to provide decision support in the choice of powertrains and energy sources for buses in public transport systems. The methodology used was a multi-criteria analysis. The assessed transportation options include buses running on diesel, biogas, fatty acid methyl esters (FAME), hydro-treated vegetable oils (HVO), bioethanol as well as battery electric vehicles (BEVs) assessed separately as opportunity and overnight charging. Suitable bus solutions were broken into six key areas to be considered when selecting fleets. These involved economic, technical, reliability, infrastructure, environmental and social issues. The economic considerations highlighted: the cost of ownership and the market share of vehicles. Vehicle performance considerations included: the range/refuel time of a vehicle. Considerations involved in delivery reliability were: national energy security, whether there was a short-term backup fuel as well as current and future policy support. Another consideration regarding infrastructure was: the required level of change required. Regarding environment and energy, considerations of merit involved: well-to-wheel greenhouse gas reductions, air pollution in relation vehicle regulations, noise levels, nutrient recyclability as well as associated resource impacts. The social considerations were determined as: public opinion and job creation. From the compiled results assessing each criterion the grading matrix suggested it was biogas buses followed closely by HVO buses that scored the best. Weighted results were also conducted, emphasizing the most important criteria according to surveyed stakeholders which resulted in HVO and Biogas again performing the best. / Många stadsplanerare, regionala myndigheter och transportleverantörer har uppgift att utföra det utmanande arbetet med att välja vilken typ av offentliga bussar som passar deras läge och prioriteringar. Utmaningarna är multidimensionella på grund av olika politikområden för att följa såväl ekonomiska, miljömässiga som tekniska avvägningar mellan alternativ. Syftet med denna rapport var att ge beslutsstöd när det gäller val av elmotorer och energikällor för bussar i kollektivtrafiksystemen. Metoden som använts var en analys av flera kriterier. De bedömda transportalternativen inkluderar bussar som körs på diesel, biogas, fettsyrametylestrar (FAME), vattenbehandlade vegetabiliska oljor (HVO), bioetanol samt batteridrivna fordon (BEV) som bedömts separat som möjlighet och över natten laddning. Lämpliga busslösningar delades upp i sex nyckelområden som ska beaktas vid val av flottor. Dessa involverade ekonomiska, tekniska, tillförlitliga, infrastrukturella, miljömässiga och sociala frågor. Ekonomiska överväganden framhävs: ägandekostnader och marknadsandelar för fordon. Fordonets prestanda överväganden inkluderade: fordonets räckvidd / tankningstid. Överväganden som berörs av leveranssäkerhet var: nationell energisäkerhet, om det fanns ett kortsiktigt backupbränsle samt nuvarande och framtida politiskt stöd. En annan hänsyn till infrastrukturen var: den nödvändiga förändringsnivån. När det gäller miljö och energi var överväganden om meriter involverade: bränslesänkningar på vägen mot växthus, luftförorening i förhållande till fordonsbestämmelser, bullernivån, återvinningsförmåga för näringsämnen samt tillhörande resurskonsekvenser. De sociala övervägandena bestämdes som: allmän åsikt och skapande av arbetstillfällen. Från de sammanställda resultaten som bedömde varje kriterium noterades att biogasbussar, som följdes noggrant av HVO-bussar, gjorde det bästa enligt graderingsskalmatrisen. Viktiga resultat genomfördes också, med betoning på de viktigaste kriterierna enligt de undersökta intressenterna, vilket resulterade i att HVO och Biogas återigen utför de bästa.

OBJECTIVES: Tools are needed for determining appropriate weights for complex performance assessment components in medical education. The feasibility of using judgmental policy capturing (JPC), a procedure to statistically describe the information processing strategies of experts, for this purpose was investigated. METHODS: Iterative JPC was used to determine appropriate weighting for the six core communication skill scores from a communications objective structured clinical examination (OSCE) for medical students using a panel of four communication skill experts. RESULTS: The mean regression weights from the panel indicated they placed less importance on information management (8.5%), moderate and nearly equal importance on rapport building (15.8%), agenda setting (15.4%), and addressing feelings (14.1%), and greater importance on active listening (20.1%) and reaching common ground with the patient (25.5%). DISCUSSION: JPC is an effective procedure for determining appropriate weights for complex clinical assessment components. The derived weights may be very different for those assessment components.

The perception of self-motion draws on inputs from the visual, vestibular and proprioceptive systems. Decades of behavioural research has shed light on constructs such as multisensory weighting, heading perception, and sensory thresholds, that are involved in self-motion perception. Despite the abundance of knowledge generated by behavioural studies, there is a clear lack of research exploring the neural processes associated with full-body, multisensory self-motion perception in humans. Much of what is known about the neural correlates of self-motion perception comes from either the animal literature, or from human neuroimaging studies only administering visual self-motion stimuli. The goal of this thesis was to bridge the gap between understanding the behavioural correlates of full-body self-motion perception, and the underlying neural processes of the human brain. We used a high-fidelity motion simulator to manipulate the interaction of the visual and vestibular systems to gain insights into cognitive processes related to self-motion perception. The present line of research demonstrated that theta, alpha and beta oscillations are the underlying electrophysiological oscillations associated with self-motion perception. Specifically, the three empirical chapters combine to contribute two main findings to our understanding of self-motion perception. First, the beta band is an index of visual-vestibular weighting. We demonstrated that beta event-related synchronization power is associated with visual weighting bias, and beta event-related desynchronization power is associated with vestibular weighting bias. Second, the theta band is associated with direction processing, regardless of whether direction information is provided through the visual or vestibular system. This research is the first of its kind and has opened the door for future research to further develop our understanding of biomarkers related to self-motion perception. / Dissertation / Doctor of Philosophy (PhD) / As we move through the environment, either by walking, or operating a vehicle, our senses collect many different kinds of information that allow us to perceive factors such as, how fast we are moving, which direction we are headed in, or how other objects are moving around us. Many of our senses take in very different information, for example, the vestibular system processes information about our head movements, while our visual system processes information about incoming light waves. Despite how different all of this self-motion information can be, we still manage to have one smooth perception of our bodies moving through the environment. This smooth perception of self-motion is due to our senses sharing information with one another, which is called multisensory integration. Two of the most important senses for collecting information about self-motion are the visual and vestibular systems. To this point, very little is known about the biological processes in the brain while the visual and vestibular systems integrate information about self-motion. Understanding this process is limited because until recently, we have not had the technology or the methodology to adequately record the brain while physically moving people in a virtual environment. Our team developed a ground-breaking set of methodologies to solve this issue, and discovered key insights into brainwave patterns that take place in order for us to perceive ourselves in motion. There were two critical insights from our line of research. First, we identified a specific brainwave frequency (beta oscillations) that indexes integration between the visual and vestibular systems. Second, we demonstrated another brainwave frequency (theta oscillation) that is associated with perceiving which direction we are headed in, regardless of which sense this direction information is coming from. Our research lays the foundation for our understanding of biological processes of self-motion perception and can be applied to diagnosing vestibular disorders or improving pilot simulator training.

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No description available.

For an environmentally sustainable society thetransportation of goods must be optimized. The next step inmaking truck transportation more sustainable is platooning.Platooning is when vehicles drive close together in a line whichrequires implementation of a control system. The aim of thisproject is to tune and implement a stabilizing controller thatcan handle various scenarios. This paper proposes a PIDcontroller to solve the problem of achieving platooning. Using asimulation environment written in Python, the PID controlleris tuned for three specific scenarios; platooning, merging andsplitting. To obtain a smooth control signal setpoint weightingwas implemented. The results presented in the report show thatPID controller can create a stable platoon for the range oftested scenarios. However, these results are purely theoreticaland while promising, more tests must be done to determine ifthe results hold in practice. / För att kunna uppnå ett hållbart samhällemåste lastbilstransporter effektiviseras. Nästa steg i utvecklingenmot mer h°allbara lastbilstransporter är konvojkörning. Konvojkörning syftar på att fordon kör nära varandra i led. Dettäar dock inte möjligt för mänskliga chaufförer att åstadkommaoch därmed krävs det något typ av kontrollsystem. Syftet medprojektet är att konstruera en kontroller som kan hanteratre stycken scenarion, nämligen konvojkörning, separering ochsammanslagning. Rapporten föreslår en PID-regulator för atthantera dessa scenarion. En simuleringsmiljö byggdes upp iPython och där justerades reglerparametrarna för att klaraav uppgiften. För att göra PID-kontrollen stabil implementeradessetpoint-weighting. Resultaten visar att PID-regulatorn kanerhålla en stabil konvoj för de utförda testerna. Resultaten ärdock helt teoretiska och även om de är lovande måste fler testergöras innan konkreta slutsatser om hur lösningen fungerar ipraktiken kan dras. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm

JPEG2000 is a wavelet transform based image compression and coding standard. It provides superior rate-distortion performance when compared to the previous JPEG standard. In addition JPEG2000 provides four dimensions of scalability-distortion, resolution, spatial, and color. These superior features make JPEG2000 ideal for use in power and bandwidth limited mobile applications like urban search and rescue. Such applications require a fast, low power JPEG2000 encoder to be embedded on the mobile agent. This embedded encoder needs to also provide superior subjective quality to low bitrate images. This research addresses these two aspects of enhancing the performance of JPEG2000 encoders. The JPEG2000 standard includes a perceptual weighting method based on the contrast sensitivity function (CSF). Recent literature shows that perceptual methods based on subband standard deviation are also effective in image compression. This research presents two new perceptual weighting methods that combine information from both the human contrast sensitivity function as well as the standard deviation within a subband or code-block. These two new sets of perceptual weights are compared to the JPEG2000 CSF weights. The results indicate that our new weights performed better than the JPEG2000 CSF weights for high frequency images. Weights based solely on subband standard deviation are shown to perform worse than JPEG2000 CSF weights for all images at all compression ratios. Embedded block coding, EBCOT tier-1, is the most computationally intensive part of the JPEG2000 image coding standard. Past research on fast EBCOT tier-1 hardware implementations has concentrated on cycle efficient context formation. These pass-parallel architectures require that JPEG2000's three mode switches be turned on. While turning on the mode switches allows for arithmetic encoding from each coding pass to run independent of each other (and thus in parallel), it also disrupts the probability estimation engine of the arithmetic encoder, thus sacrificing coding efficiency for improved throughput. In this research a new fast EBCOT tier-1 design is presented: it is called the Split Arithmetic Encoder (SAE) process. The proposed process exploits concurrency to obtain improved throughput while preserving coding efficiency. The SAE process is evaluated using three methods: clock cycle estimation, multithreaded software implementation, a field programmable gate array (FPGA) hardware implementation. All three methods achieve throughput improvement; the hardware implementation exhibits the largest speedup, as expected. A high speed, task-parallel, multithreaded, software architecture for EBCOT tier-1 based on the SAE process is proposed. SAE was implemented in software on two shared-memory architectures: a PC using hyperthreading and a multi-processor non-uniform memory access (NUMA) machine. The implementation adopts appropriate synchronization mechanisms that preserve the algorithm's causality constraints. Tests show that the new architecture is capable of improving throughput as much as 50% on the NUMA machine and as much as 19% on a PC with two virtual processing units. A high speed, multirate, FPGA implementation of the SAE process is also proposed. The mismatch between the rate of production of data by the context formation (CF) module and the rate of consumption of data by the arithmetic encoder (AE) module is studied in detail. Appropriate choices for FIFO sizes and FIFO write and read capabilities are made based on the statistics obtained from test runs of the algorithm. Using a fast CF module, this implementation was able to achieve as much as 120% improvement in throughput. / Ph. D.