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Πλευρική εξάπλωση στην παραλιακή ζώνη του Ληξουρίου και Αργοστολίου κατά τους σεισμούς της Κεφαλονιάς στις 26-1- & 03-2-2014Κεχαγιάς, Γιώργος 26 April 2015 (has links)
H πλευρική εξάπλωση είναι ένα εντυπωσιακό-καταστροφικό φαινόμενο,
επακόλουθο της ρευστοποίησης, που οδηγεί στην εδαφική αστοχία. Στην περίπτωση
κεκλιμένων εδαφών ή εδαφών που καταλήγουν σε ελεύθερο μέτωπο, προκαλείται
έντονη ρηγμάτωση της επιφάνειας του εδάφους και Πλευρική Εξάπλωση, Lateral
Spreading, (δηλαδή οριζόντια μετακίνηση) του εδαφικού υλικού (παραμορφώσεις
πολύπλοκης μορφής), στην περιοχή της όχθης υδάτινων ρευμάτων ή άλλων
θαλασσίων μετώπων και η εξάπλωση αυτών σε μεγάλη απόσταση προς τα ανάντι.
Αντικείμενο της παρούσας Διατριβής αποτελεί η μελέτη της εκτεταμένης
πλευρικής εξάπλωσης που πραγματοποιήθηκε υπό συνθήκες ελευθέρου μετώπου
προς την κατεύθυνση της ακτογραμμής στο Δυτικό Κρηπίδωμα του Λιμένα
Ληξουρίου και στην παραλιακή ζώνη του Αργοστολίου κατά τους σεισμούς της
Κεφαλονιάς στις 26-1-2014 (Mw=6.1) και στις 03-2-2014 (Mw=6.0).
Η Διατριβή περιλαμβάνει παρουσίαση των διαθέσιμων γεωτεχνικών
δεδομένων για το λιμένα Ληξουρίου και εκτιμήσεις του μεγέθους της πλευρικής
εξάπλωσης με βάση τα σύγχρονα εμπειρικά μοντέλα του Youd et al. (2002) και την
τροποποίηση αυτού, Youd et al. (2013). Γίνεται επίσης, σύγκριση της μετρηθείσας
οριζόντιας μετακίνησης με τις προβλέψεις των οριζόντιων μετακινήσεων των δύο
μοντέλων. Για τον έλεγχο της ρευστοποιησιμότητας του εδάφους -με χρήση του
αριθμού κτύπων NSPT - με σκοπό τον υπολογισμό του αθροιστικού ρευστοποιήσιμου
πάχους Τ15, χρησιμοποιήθηκε η μεθοδολογία των Idriss and Boulanger (2006).
Τέλος, παρουσιάζονται τα διαγράμματα μετρημένης οριζόντιας αθροιστικής
μετακίνησης - απόστασης από το ελεύθερο μέτωπο για την παραλιακή ζώνη του
Αργοστολίου. Λόγω έλλειψης γεωτεχνικών δεδομένων για το Αργοστόλι δεν έγινε
δυνατή η σύγκριση των μετρημένων τιμών με τις εκτιμηθείσες από εμπειρικά
μοντέλα. Ωστόσο, οι τιμές αυτές μπορούν να αποτελέσουν χρήσιμη προσθήκη στην
υφιστάμενη βάση δεδομένων για βελτίωση των εμπειρικών μοντέλων και καλύτερη
εφαρμογή τους στον ελλαδικό χώρο. / Lateral Spreading along the coastal line of Liksouri and Argostoli during the earthquakes in Cephalonia in January 26 & February 3, 2014.
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Reversible decortication and habituation of reactions to novelty.Nadel, Lynn. January 1965 (has links)
Repetitive presentation of any non-significant stimulus to an animal results in a decrement in the animal's response to that stimulus. This phenomenon, termed habituation, is distinguishable from fatigue and receptor adaptation in that it is long-lasting and in that the habituation is fairly specific to the repeated stimulus. The prevailing view of habituation is that it, like learning in general, results from an increase in the efficacy of neural transmission, but, unlike learning, this increased efficacy primarily affects inhibitory interneurons (e.g., Soko1ov, 1960; Hernandez-Peon, 1960; Jouvet, 1961). Within this broad framework, disagreements exist regarding the source of the inhibitory influences. [...]
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Prostitucijos paplitimo kriminologinis tyrimas Europos Sąjungos kontekste / Criminological Research of Spreading of Prostitution in the Context of the European UnionPajaujienė, Rasa 24 January 2011 (has links)
Prostitucija laikoma viena seniausių pasaulio profesijų, kurios kriminalizavimas pradėtas viduramžiuose, keičiantis visuomenės vertybėms, visuomenės požiūriui į moterį, stiprėjant bažnyčios įtakai. Šiais laikais prostitucija vertinama kaip socialinė daugialypė problema, kurios sprendimo reikia ieškoti jos pačios priežastyse. Toks požiūris į prostituciją suteikia darbui aktualumo, išgryninant jį per legalumo prizmę atskirose valstybėse, pagrindžia poreikį darbe atliktam tyrimui ir, remiantis jo rezultatais, pagrindžia naujumą, kadangi darbe panaudotas 121 literatūros šaltinis, dar apie 50 šaltinių peržvelgtų, tačiau darbe nepanaudotų, neatskleidžia pilnai prostitucijos paplitimo mastų visoje Europos Sąjungoje. Atskiri šaltiniai analizuoja atskirus aspektus, pateikia atskirus žemėlapius, tačiau pateikia tik atskirų valstybių faktus, be jokių jų kitimo dinamikų ir tendencijų, be jokių lyginamųjų analizių. Tai reiškia, kad nėra išsamių tyrimų, analizių viso prostitucijos fenomeno aspektu – pradedant paplitimo mastų žemėlapiais, priežastimis, pasekmėmis, teisinėmis reguliavimo priemonėmis, prevencijos mechanizmais, apie kuriuos mokslininkai atskirose valstybėse kalba itin mažai.
Darbo tikslas - charakterizuoti prostituciją kaip nusikaltimą Europos Sąjungos valstybėse. Šio tikslo siekimas leido išanalizuoti prostitucijos kaip reiškinio daugialypiškumą, išskiriant priežastis bei pasekmes, pateikiant jos paplitimo mastus, pažymint, kad net tose valstybėse, kuriose prostitucija yra... [toliau žr. visą tekstą] / Prostitution is thought to be one of the oldest professions in the world that was started to be criminalized in the Middle Ages after the changes in the societies’ value, attitudes to women, increasing power of churches. Nowadays prostitution is a complex and multiple phenomenons. This problem should be solved looking for the solutions in the causes of prostitution. Such an angle to prostitution reveals the relevance of the theme, making it clear through the legal aspects of this phenomenon in different EU members. The results of the research show that this research is quite new. There were 121 references used and about 50 more articles, books, reports analyzed in this research and the analysis allows concluding that different authors and different organizations research, analyze just the detached facts without any trends, not taking into account the whole phenomenon. That means that there are no comprehensive researches done in this field.
The goal of this paper is to characterize prostitution as a criminal activity in the European Union. Seeking this goal allowed analyzing the multiplicity of prostitution, defining the causes and outcomes, presenting the spreading of this phenomenon, showing that prostitution has the elements of criminal activity even in the countries it is legal.
The Paper consists of preface, three main parts and conclusions. In the first part of the Paper the theoretical aspects of prostitution are being analyzed. The second part presents the results of... [to full text]
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Dogbane Beetle (Chrysochus auratus Fab.) as a Biological Control Agent of Spreading Dogbane (Apocynum androsaemifolium L.)MacEachern, Megan C. 04 October 2012 (has links)
Dogbane beetle, Chrysochus auratus, was studied for its biological control potential against spreading dogbane, Apocynum androsaemifolium, a native perennial weed in lowbush blueberry (Vaccinium angustifolium). No-choice host range experiments were conducted with common milkweed (Asclepias syriaca), periwinkle (Vinca minor), wild raisin (Viburnum cassenoides), and lowbush blueberry. There was no significant feeding on these plant species by adult dogbane beetles. Significant decreases in foliar dry weight were achieved with 16 beetles per ramet. In Nova Scotia, beetles were present in the field for 8-12 weeks beginning in late June or early July (225-335 growing degree days). Peak beetle abundance occured at 357-577 growing degree days and varied from 4-7 beetles/m2. The fecundity and fertility, timing of pupation, and number of instars were also examined. Females deposited approximately 100 eggs over a 20 day period, with an egg viability of over 90%. Pupae were found on June 1st and June 15th. / A unique project exploring biological control of a native plant species using a native insect species
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Modelling subphonemic information flow : an investigation and extension of Dell's (1986) model of word productionMoat, Helen Susannah January 2011 (has links)
Dell (1986) presented a spreading activation model which accounted for a number of early speech error results, including the relative proportions of anticipations, perseverations and exchanges found in speech error corpora, the lexical bias effect, the phonological similarity effect, and the effect of speech rate on error rate. This model has had an immense influence on the past 20 years of research into word production, with the original paper being cited over 1,000 times. Many studies have questioned how activation should flow between words and phonemes in this model. This thesis aimed to clarify what current speech error evidence tells us about how activation flows between phonemes and subphonemic representations, like features. Does activation cascade from phonemes to features, and does it feed back? The work presented here extends previous modelling investigations in two ways. Firstly, whereas previous modelling research has tended to evaluate model behaviour using arbitrarily chosen parameter settings, we illuminate the influence of the parameters on model behaviour and propose methods to draw general conclusions about model behaviour from large numbers of simulations at orthogonally varied parameter settings. Secondly, we extend the scope of the simulations to consider output at a subphonemic level, modelling recent data acquired via acoustic and articulatory measurements, such as voicing onset time (VOT), electropalatography (EPG) and ultrasound, alongside older transcribed speech error data. Throughout the thesis, we consider whether parameter settings which lead the model to capture individual results also permit other results to be accounted for and do not cause otherwise implausible behaviour. Through manipulating parameter settings in Dell's (1986) original model, we find that increasing the number of steps before selection generally does not decrease the error rate, but rather increases it, contrary to results reported by Dell (1986). This calls into question the claim that an increase in steps before selection provides a good model of a slower speech rate. We also demonstrate that the model captures the negative correlation reported by Dell, Burger, and Svec (1997) between error rate and the ratio of anticipations to perseverations, and further predicts that there should be a negative correlation between this ratio and the proportion of errors which are non-contextual. However, our results show that no parameter setting allows the model to generate enough exchanges to match even minimum estimates from a reanalysis of multiple speech error corpus reports, without falling foul of other constraints; in particular, limits on the overall number of errors generated. We suggest that the exchange completion triggering mechanism proposed by Dell (1986) is not strong enough, and that current corpus evidence provides little support for his account of word sequencing. Focusing on single word production therefore, the second part of the thesis investigates behaviour of models with output at a subphonemic level. We find that, provided sufficient contextual errors occur at the featural level, a model in which only the identity of the selected phoneme is conveyed to the featural level can account for: (i) the phonological similarity effect found in transcribed records of speech errors (whereas in models with output at the phoneme level, feedback from features to phonemes is required); (ii) detectable influences of intended phonemes in VOT measurements of unintended phonemes, as well as the effect of error outcome lexicality on these results ( findings presented in support of cascading from phonemes by Goldrick & Blumstein, 2006); and (iii) increased similarity of EPG measurements of articulations to reference measurements of competing articulations when production of the competing onset would result in a word (McMillan, Corley, & Lickley, 2009). Initial results appear to con firm however that, in contrast, phonological similarity effects on the relationship of articulatory and acoustic measurements of productions to reference measurements (McMillan, 2008) can only be accounted for in an architecture with feedback from features to phonemes. To strengthen conclusions about articulatory evidence of lexical bias and phonological similarity effects, future work needs to consider the extremely strong effects of frequency observed in these simulations. The results presented in this thesis contribute to a greater comprehension of the behaviour of Dell's (1986) influential model, and further demonstrate that the model can be extended to account for new instrumental evidence, whilst clarifying the constraints on activation flow between phonemes and features which this new evidence imposes.
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Randomized Resource Allocaion in Decentralized Wireless NetworksMoshksar, Kamyar January 2011 (has links)
Ad hoc networks and bluetooth systems operating over the unlicensed ISM band are in-stances of decentralized wireless networks. By definition, a decentralized network is com-posed of separate transmitter-receiver pairs where there is no central controller to assign the resources to the users. As such, resource allocation must be performed locally at each node. Users are anonymous to each other, i.e., they are not aware of each other's code-books. This implies that multiuser detection is not possible and users treat each other as noise. Multiuser interference is known to be the main factor that limits the achievable rates in such networks particularly in the high Signal-to-Noise Ratio (SNR) regime. Therefore, all users must follow a distributed signaling scheme such that the destructive effect of interference on each user is minimized, while the resources are fairly shared.
In chapter 2 we consider a decentralized wireless communication network with a fixed number of frequency sub-bands to be shared among several transmitter-receiver pairs. It is assumed that the number of active users is a realization of a random variable with a given probability mass function. Moreover, users are unaware of each other's codebooks and hence, no multiuser detection is possible. We propose a randomized Frequency Hopping (FH) scheme in which each transmitter randomly hops over a subset of sub-bands from transmission slot to transmission slot. Assuming all users transmit Gaussian signals, the distribution of the noise plus interference is mixed Gaussian, which makes calculation of the mutual information between the transmitted and received signals of each user intractable. We derive lower and upper bounds on the mutual information of each user and demonstrate that, for large SNR values, the two bounds coincide. This observation enables us to compute the sum multiplexing gain of the system and obtain the optimum hopping strategy for maximizing this quantity. We compare the performance of the FH system with that of the Frequency Division (FD) system in terms of the following performance measures: average sum multiplexing gain and average minimum multiplexing gain per user. We show that (depending on the probability mass function of the number of active users) the FH system can offer a significant improvement in terms of the aforementioned measures. In the sequel, we consider a scenario where the transmitters are unaware of the number of active users in the network as well as the channel gains. Developing a new upper bound on the differential entropy of a mixed Gaussian random vector and using entropy power inequality, we obtain lower bounds on the maximum transmission rate per user to ensure a specified outage probability at a given SNR level. We demonstrate that the so-called outage capacity can be considerably higher in the FH scheme than in the FD scenario for reasonable distributions on the number of active users. This guarantees a higher spectral efficiency in FH compared to FD.
Chapter 3 addresses spectral efficiency in decentralized wireless networks of separate transmitter-receiver pairs by generalizing the ideas developed in chapter 2. Motivated by random spreading in Code Division Multiple Access (CDMA), a signaling scheme is introduced where each user's code-book consists of two groups of codewords, referred to as signal codewords and signature codewords. Each signal codeword is a sequence of independent Gaussian random variables and each signature codeword is a sequence of independent random vectors constructed over a globally known alphabet. Using a conditional entropy power inequality and a key upper bound on the differential entropy of a mixed Gaussian random vector, we develop an inner bound on the capacity region of the decentralized network. To guarantee consistency and fairness, each user designs its signature codewords based on maximizing the average (with respect to a globally known distribution on the channel gains) of the achievable rate per user. It is demonstrated how the Sum Multiplexing Gain (SMG) in the network (regardless of the number of users) can be made arbitrarily close to the SMG of a centralized network with an orthogonal scheme such as Time Division (TD). An interesting observation is that in general the elements of the vectors in a signature codeword must not be equiprobable over the underlying alphabet in contrast to the use of binary Pseudo-random Noise (PN) signatures in randomly spread CDMA where the chip elements are +1 or -1 with equal probability. The main reason for this phenomenon is the interplay between two factors appearing in the expression of the achievable rate, i.e., multiplexing gain and the so-called interference entropy factor. In the sequel, invoking an information theoretic extremal inequality, we present an optimality result by showing that in randomized frequency hopping which is the main idea in the prevailing bluetooth devices in decentralized networks, transmission of independent signals in consecutive transmission slots is in general suboptimal regardless of the distribution of the signals.
Finally, chapter 4 addresses a decentralized Gaussian interference channel consisting of two block-asynchronous transmitter-receiver pairs. We consider a scenario where the rate of data arrival at the encoders is considerably low and codewords of each user are transmitted at random instants depending on the availability of enough data for transmission. This makes the transmitted signals by each user look like scattered bursts along the time axis. Users are block-asynchronous meaning there exists a delay between their transmitted signal bursts. The proposed model for asynchrony assumes the starting point of an interference burst is uniformly distributed along the transmitted codeword of any user. There is also the possibility that each user does not experience interference on a transmitted codeword at all. Due to the randomness of delay, the channels are non-ergodic in the sense that the transmitters are unaware of the location of interference bursts along their transmitted codewords. In the proposed scheme, upon availability of enough data in its queue, each user follows a locally Randomized Masking (RM) strategy where the transmitter quits transmitting the Gaussian symbols in its codeword independently from symbol interval to symbol interval. An upper bound on the probability of outage per user is developed using entropy power inequality and a key upper bound on the differential entropy of a mixed Gaussian random variable. It is shown that by adopting the RM scheme, the probability of outage is considerably less than the case where both users transmit the Gaussian symbols in their codewords in consecutive symbol intervals, referred to as Continuous Transmission (CT).
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Interception Techniques For Direct Sequence Spread Spectrum SignalsKaradeniz, Uygar 01 December 2005 (has links) (PDF)
In this work interception and spreading sequence estimation of Direct Sequence Spread Spectrum (DSSS) signals, in low signal to noise power ratios is discussed. For interception an approach based on autocorrelation fluctuations is employed
and also symbol period is estimated from this interception process. Spreading sequence estimation is performed by using eigenanalysis of the correlation matrix and estimated symbol period. These approaches are applied on different kinds of DSSS signals including 3rd generation UMTS signal and LPI radar signals. In order to examine the channel effects such as / multipath, interference and colored noise, on the performance of applied techniques, detailed analysis results are obtained. The results are compared with the performances of alternative interception techniques.
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Coding-spreading tradeoff in CDMA systems /Bolas, Eduardo J. January 2002 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, September 2002. / Thesis advisor(s): Tri T. Ha, Jan E. Tighe, Jovan E. Lebaric. Includes bibliographical references (p. 85). Also available online.
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Magma chamber structure and Moho reflections along the East Pacific Rise /Babcock, Jeffrey Matthew, January 1997 (has links)
Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references.
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Seafloor spreading processes in protoarc-forearc settings eastern Albanian ophiolite as a case study /Phillips, Charity M.. January 2004 (has links)
Thesis (M.S.)--Miami University, Dept. of Geology, 2004. / Title from first page of PDF document. Includes bibliographical references (p. 126-129).
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