This diploma thesis deals with monitoring of persons in an enclosed space. The goal of this thesis is to get acquainted with the issue of indoor localization and the subsequent creation of own solution using the ultrasound technology. Ultrasound technology should eliminate some deficiency of current technologies. The theoretical part includes the overview of some current methods. Last part of the thesis verifies the function of device.

This diploma thesis deals with monitoring of persons in an enclosed space. The goal of this thesis is to get acquainted with the issue of indoor localization and the subsequent creation of own solution using the ultrasound technology. Ultrasound technology should eliminate some deficiency of current technologies. The theoretical part includes the overview of some current methods. Last part of the thesis verifies the function of device.

Echolocation is using lagging sounds as cues to localize the objects reflecting them. The precedence effect (PE) occurs when echoic signals are suppressed in favour of leading signals. In this study, the ability of nine listeners to overcome the PE when detecting and lateralizing echoic signals through headphones was measured and compared. Threshold estimates of the lead-lag ratio (dB) for lead-lag click-pairs at eight different inter-click intervals (ICIs) between 6-200ms were obtained. Further, two listeners trained each task at two ICIs (12 and 200ms) for seven days to investigate training, and transfer of training, effect between tasks. The results revealed that the PE is still present in lateralization tasks when ICI is at least 48ms. A threshold level difference between echo detection and lateralization was observed, indicating a possibility of different processing mechanisms between tasks. No training effects were found although longer training periods could provide more answers to what lies behind the ability to overcome the PE and echolocate efficiently in everyday life.

Different cognitive processes underlie the perception of vocalizations in many mammals, including humans. This perception now extends to a highly specialized form of sonar called echolocation. In habituation-dishabituation experiments, a high duty cycle echolocating bat, Rhinolophus clivosus, dishabituated significantly when echolocation calls of a different gender or individual were played to the habituation. Strong individual and gender signatures but weak geographic signatures were found in both the CF and FM components of their echolocation calls. In the individual discrimination trials reactions were more pronounced to an individual that was less acoustically similar to the habituation than to one that was more similar. Bats reacted to playbacks with a variety of social behaviours. Prior to the analysis of the experiment an ethogram was done on three groups of captive R. clivosus bats. This ethogram was used to categorize the behavioural responses of these bats to the acoustic stimuli in the experiments. The reactions to the habituation-dishabituation experiments show bats perceive gender and individual-specific signatures found in their conspecifics echolocation calls. This is the first study to show behavioural evidence for individual discrimination and second to show gender discrimination of echolocation calls in high duty cycle bats. This evidence supports the theory that echolocation, a system thought to have evolved solely for orientation and foraging, has been coopted for intra-specific communication and mate recognition in bats.

The synchronization of flight mechanics with respiration and echolocation call emission by bats, while economizing these behaviors, presumably puts compressive loads on the cartilaginous rings that hold open the respiratory tract. Previous work has shown that during postnatal development of Artibeus jamaicensis (Phyllostomidae), the onset of adult echolocation call emission rate coincides with calcification of the larynx, and the development of flight coincides with tracheal ring calcification. In the present study, I assessed the level of reinforcement of the respiratory system in 13 bat species representing six families that use stereotypical modes of echolocation (i.e. duty cycle % and intensity). Using computed tomography, the degree of mineralization or ossification of the tracheal rings, cricoid, thyroid and arytenoid cartilages were determined for non-echolocators, tongue clicking, low-duty cycle low-intensity, low-duty cycle high-intensity, and high-duty cycle high-intensity echolocating bats. While all bats had evidence of cervical tracheal ring mineralization, about half the species had evidence of thoracic tracheal ring calcification. Larger bats (Phyllostomus hastatus and Pterpodidae sp.) exhibited more extensive tracheal ring mineralization, suggesting an underlying cause independent of laryngeal echolocation. Within most of the laryngeally echolocating species, the degree of mineralization or ossification of the larynx was dependent on the mode of echolocation system used. Low-duty cycle low-intensity bats had extensively mineralized cricoids, and zero to very minor mineralization of the thyroids and arytenoids. Low-duty cycle high-intensity bats had extensively mineralized cricoids, and patches of thyroid and arytenoid mineralization. The high-duty cycle high-intensity rhinolophids and hipposiderid had extensively ossified cricoids, large patches of ossification on the thyroids, and heavily ossified arytenoids. The high-duty cycle high-intensity echolocator, Pteronotus parnellii, had mineralization patterns and laryngeal morphology very similar to the other low-duty cycle high-intensity mormoopid species, perhaps suggesting relatively recent evolution of high-duty cycle echolocation in P. parnellii compared with the Old World high-duty cycle echolocators (Rhinolophidae and Hipposideridae). All laryngeal echolocators exhibited mineralized or ossified lateral expansions of the cricoid for articulation with the inferior horn of the thyroid, these were most prominent in the high-duty cycle high-intensity rhinolophids and hipposiderid, and least prominent in the low-duty cycle low-intensity echolocators. The non-laryngeal echolocators had extensively ossified cricoid and thyroid cartilages, and no evidence of mineralization/ossification of the arytenoids or lateral expansions of the cricoid. While the non-echolocators had extensive ossification of the larynx, it was inconsistent with that seen in the laryngeal echolocators.

Blind  people use echoes to detect  objects  and  to  find their  way, the  ability  being known as human echolocation.   Previous  research  have found some of the  favorable  conditions  for the  detection  of the object,  with  many  factors  yet  to  be analyzed  and  quantified.    Studies  have  also shown  that blind people are more efficient than  the  sighted  in echolocating,  with  the  performance  varying  among  the individuals.   This  motivated the  research  in human  echolocation  to move in a new direction  to get a fuller understanding for the high detection  of the blind.  The psychoacoustic  experiments solely cannot determine  how the superior echo detection  of the blind listeners should be attributed to perceptual or physiological causes.  Along with the perceptual results it is vital to know how the sounds are processed in the  auditory system.   Hearing  research  has led to the  development of several auditory  models by combining  the  physiological  and  psychological  results  with  signal  analysis  methods.    These  models try  to describe how the auditory system  processes the signals.  Hence, to analyze how the sounds are processed for the high detection  of the blind, auditory  models available  in the literature were used in this thesis.  The results  suggest  that repetition pitch  is useful at  shorter  distances  and is determined from the peaks in the temporal  profile of the autocorrelation function computed  on the neural activity pattern. Loudness attribute also plays a role in providing information  for the listeners to echolocate at shorter  distances.  At longer distances  timbre  aspects such as sharpness  information  might be used by the listeners  to detect  the objects.  It was also found that the repetition pitch,  loudness and sharpness attributes in turn  depend on the room acoustics  and type of the stimuli  used.  These results  show the fruitfulness  of combining  results  from different  disciplines  through  a mathematical framework  given by signal analysis.

The lineage that gave rise to mammals split from other basal amniotes, approximately 300 million years ago. Since then, mammals have evolved many sensory novelties, including high-frequency hearing and echolocation. Sensitivity to high frequencies is particularly well developed in many echolocating mammals; for example, the upper hearing limit of several laryngeal echolocating bat species are estimated to be approximately ten times that of humans. In order to process the high frequency sounds produced during echolocation, the inner ears of laryngeal echolocating bats have undergone substantial modifications. Despite the evolutionary significance of laryngeal echolocation, it is unknown how many times it evolved within bats. Its occurrence on most, but not all, bat lineages suggests it either evolved once with secondary loss, or independently on multiple lineages. Distinguishing between these possibilities is complicated by morphological diversity and convergence. Furthermore, the genetic basis underpinning echolocation remains largely unknown. To elucidate the evolutionary history of this key trait in bats, a combined molecular and morphological approach was taken. Firstly, for two mammalian ‘hearing genes’ sequence convergence, phylogenetic signal and selection pressures were examined across echolocating and non-echolocating mammal species. Secondly, substitution rates of Conserved Non-coding Elements associated with genes regulating ear development were compared across mammals. Finally, as mammalian inner ear development is controlled by many genes, the gross structure of the bony labyrinth was studied in order to examine the combined genetic effect. Structural variation of bat cochleae and vestibular systems was examined using micro-computed tomography reconstructions, and related to ecological data. Subsequent analyses found evidence of convergence at the molecular level, in terms of amino acid substitutions, and also the morphological level, in terms of inner ear morphology. No evidence of degeneration, supporting loss-of-function in Old World fruit bats was found. Conversely, evidence of differential evolution pressures acting on the two echolocating bat lineages was found, which supports multiple origins of laryngeal echolocation in bats.

<p>Both blind and sighted persons may use echoes for detecting objects.</p><p>The effect of object size on echolocation was tested in a listening</p><p>experiment with 15 sighted participants. Noise burst of 500-ms were</p><p>generated and recorded in an ordinary room, with and without a</p><p>reflecting object. The diameter of the reflecting object was 0.25 or</p><p>0.50 m, and it was located at a distance of 0.5, 1, 2, 3 m from the</p><p>microphones. Pairs of sounds, one with and one without the object,</p><p>were presented to the listeners. Their task was to decide which of the</p><p>two sounds that were recorded with the reflecting object. The results</p><p>showed that it was harder to detect the 0.25 than the 0.5 m object, and</p><p>that performance generally decreased with distance. The auditory</p><p>angle, which is a function of the size to distance ratio, was found to</p><p>predict detection performance fairly well.</p><p>Sighted</p>

Both blind and sighted persons may use echoes for detecting objects. The effect of object size on echolocation was tested in a listening experiment with 15 sighted participants. Noise burst of 500-ms were generated and recorded in an ordinary room, with and without a reflecting object. The diameter of the reflecting object was 0.25 or 0.50 m, and it was located at a distance of 0.5, 1, 2, 3 m from the microphones. Pairs of sounds, one with and one without the object, were presented to the listeners. Their task was to decide which of the two sounds that were recorded with the reflecting object. The results showed that it was harder to detect the 0.25 than the 0.5 m object, and that performance generally decreased with distance. The auditory angle, which is a function of the size to distance ratio, was found to predict detection performance fairly well. Sighted

Η παρούσα διπλωματική εργασία πραγματεύεται τον σχεδιασμό ενός πρωτότυπου μετρητικού συστήματος που έχει ως εφαρμογή τον εντοπισμού απόστασης ενός αντικειμένου από ένα ζεύγος πομπού/δέκτη αισθητήρων με χρήση υπερήχων. Ο πομπός εκπέμπει ένα σήμα δημιουργούμενο από έναν μικροελεγκτή, το οποίο ανακλάται πάνω στο δοθέν αντικείμενο και επιστρέφει στον δέκτη, από τον οποίο έπειτα από σχετική μορφοποίηση οδηγείται πίσω στον μικροελεγκτή προς επεξεργασία. Στην συνέχεια τα δεδομένα οδηγούνται σε έναν προσωπικό υπολογιστή, όπου και μπορούν να υποστούν οποιαδήποτε επεξεργασία και να τα εκμεταλλευτούμε με οποιονδήποτε τρόπο. Γι αυτόν τον λόγο σχεδιάστηκε μια απλή και εύχρηστη διεπαφή για το χειρισμό του συστήματος, η χρήση του οποίου βρίσκει μεγάλη εφαρμογή σε μετρητικές διατάξεις στις οποίες είναι επιθυμητή η ταχύτητα και η ακρίβεια. / The goal of this diploma thesis is to design a prototypical measuring system that has application in the location of an object by using a pair of ultrasound transceivers. The transmitter emits a signal that is generated by a microcontroller, which is reflected on the given object, returning to the receiver, though which is modified so as to be processed by said microcontroller again. After that, the results are sent to a personal computer to be used in any way possible. For that very reason a simple, yet handy, interface is developed so as to control the system, which can be used in measuring arrays that demand great speed and precision.