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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Ernst Jünger - eine Annäherung an Drogen - Medizinische Analyse seiner LSD-Versuche / Ernst Jünger – An Approach to Drugs – A Medical Analysis of his LSD–Experiments

Coenen, Corinna Maria Odilia 29 May 2012 (has links)
No description available.
32

Desenvolvimento de métodos voltamétricos para a quantificação de LSD utilizando-se o eletrodo de pasta de carbono modificado com complexo de base de Schiff / Development of voltammetric methods for the quantification of LSD using a carbon paste electrode modified by a Schiff base complex

Maria Fernanda Muzetti Ribeiro 29 October 2015 (has links)
Nos últimos anos, vários métodos eletroanalíticos foram desenvolvidos a fim de tornarem mais práticas e acessíveis às análises químicas de substâncias entorpecentes realizadas pela polícia científica. Com a sensibilidade e seletividade compatíveis com as dos métodos instrumentais convencionais, é a portabilidade da técnica eletroanalítica que se sobressai e tem apresentado grande potencial para tais aplicações. O uso de complexos metálicos com as bases de Schiff como modificadores do eletrodo de trabalho, tornou ainda mais promissora a utilização destes métodos para a detecção e quantificação de entorpecentes. Os eletrodos de pasta de carbono também contribuem para a praticidade da eletroanalítica, uma vez que são produzidos de forma simples e barata. Desta forma, neste projeto foram desenvolvidos métodos voltamétricos para a quantificação da dietilamida do ácido lisérgico (LSD), utilizando-se o eletrodo de pasta de carbono modificado com o complexo [UO2(Ac-ophen)]·H2O. A aplicação do KCl como eletrólito suporte, em solução aquosa, diferencia estes métodos do encontrado na literatura. Nas análises, foram empregadas as técnicas de voltametria cíclica, onda quadrada e de pulso diferencial. A linearidade no aumento da corrente frente às variações da concentração do LSD possibilitou a obtenção das curvas analíticas com desvio padrão e limites de detecção e quantificação de 2,45, 0,62 e 1,02 mol L-1, respectivamente, como melhores resultados. As análises de recuperação das amostras, 103 e 108%, demostra a possibilidade da utilização destas no âmbito forense. / The development of electroanalytical methods for forensic science has been growing in recent years by the fact of their practicality and low cost. Once sensibility and selectivity values are compatible to conventional methods, as chromatography and spectrometry, the portability of this system consists on interesting advantages. The simple modification of the carbon paste working electrode with Schiff bases complexes became even more promising to use this method for the detection and quantification of narcotics. The carbon paste electrode itself contributes for the practicality of the analyses, once it is made of simple carbon powder, which can be disposable. This project aimed to develop voltammetric methods for the quantification of the lysergic acid diethylamide (LSD) using a carbon paste electrode modified with the complex [UO2(Ac-ophen)]·H2O. The use of aqueous solution of KCl as supporting electrolyte characterizes a less pollutant methodology, differently of other methods that still use toxic solvents The combination of the differential pulse and square wave voltammetries with the modified carbon paste was crucial for the detection of trace levels of the LSD. The linear response in various concentrations of LSD results on analytical curves with standard deviation, detection, and quantification limits of 2,45, 0,62, 1,02 mol L-1, respectively. And the recovery values of 103 and 108 % indicates the possibility of using this method in the forensic science
33

Detection algorithms and architectures for wireless spatial multiplexing in MIMO-OFDM systems

Myllylä, M. (Markus) 17 May 2011 (has links)
Abstract The development of wireless telecommunication systems has been rapid during the last two decades and the data rates as well as the quality of service (QoS) requirements are continuously growing. Multiple-input multiple-output (MIMO) techniques in combination with orthogonal frequency-division multiplexing (MIMO–OFDM) have been identified as a promising approach for high spectral efficiency wideband systems. The optimal detection method for a coded MIMO–OFDM system with spatial multiplexing (SM) is the maximum a posteriori (MAP) detector, which is often too complex for systems with high order modulation. Suboptimal linear detectors, such as the linear minimum mean square error (LMMSE) criterion based detection, offer low complexity solutions, but have poor performance in correlated fading channels. A list sphere detector (LSD) is a tree search based soft output detector that can be used to approximate the MAP detector with a lower computational complexity. The benefits of the more advanced detectors can be realized especially in a low SNR environment by, e.g., increasing the cell coverage. In this thesis, we consider the linear minimum mean square error (LMMSE) criterion based detectors and more advanced LSDs for detection of SM transmission. The LSD algorithms are not as such feasible for hardware implementation. Therefore, we identify the design choices that relate to the performance and implementation complexity of the LSD algorithms. We give guidelines to the LSD algorithm design and propose the proper trade-off solutions for practical wireless systems. The more stringent requirements call for further research on architectures and implementation. In particular, it is important to address the parallelism and pipelining factors in the architecture design to enable an optimal trade-off between used resources and operating speed. We design pipelined systolic array architecture for LMMSE detector algorithms and efficient architectures with given algorithm properties for the LSD algorithms. We consider the VLSI implementation of the algorithms to study the true performance and complexity. The designed architectures are implemented on a field programmable gate array (FPGA) chip and CMOS application specific integrated circuit (ASIC) technology. Finally, we present some measurement results with a hardware testbed to verify the performance of the considered algorithms. / Tiivistelmä Langattoman tietoliikenteen kehitys on ollut nopeaa viimeisien vuosikymmenien aikana ja järjestelmiltä vaaditaan yhä suurempia datanopeuksia ja luotettavuutta. Multiple-input multiple-output (MIMO) tekniikka yhdistettynä monikantoaaltomodulointiin (MIMO-OFDM) on tunnistettu lupaavaksi järjestelmäksi, joka mahdollistaa tehokkaan taajuusalueen hyödyntämisen. Optimaalinen ilmaisumenetelmä tilakanavoituun (SM) ja koodattuun MIMO-OFDM järjestelmään on maximum a posteriori (MAP) ilmaisin, joka on tyypillisesti liian kompleksinen toteuttaa laajakaistajärjestelmissä, joissa käytetään korkean asteen modulointia. Alioptimaaliset lineaariset ilmaisimet, kuten pienimpään keskineliövirheeseen (LMMSE) perustuvat ilmaisimet, ovat suhteellisen yksinkertaisia toteuttaa nykyteknologialla, mutta niiden suorituskyky on varsin heikko korreloivassa radiokanavassa. Listapalloilmaisin (LSD) on puuhakualgoritmiin perustuva pehmeän ulostulon ilmaisin, joka pystyy jäljittelemään MAP ilmaisinta sitä pienemmällä kompleksisuudella. Kehittyneemmät ilmaisimet, kuten LSD, voivat parantaa langattoman verkon suorituskykyä erityisesti ympäristössä, jossa on matala signaalikohinasuhde, esimerkiksi mahdollistamalla suuremman toiminta-alueen. Tässä väitöskirjassa on tutkittu kahta LMMSE ilmaisinta ja kolmea LSD ilmaisinta SM lähetyksen ilmaisuun. Yleisesti LSD algoritmit eivät ole sellaisenaan toteutuskelpoisia kaupallisiin järjestelmiin. Väitöskirjassa on tämän vuoksi tutkittu LSD:n toteutukseen liittyviä haasteita ja toteutusmenetelmiä ja annetaan suosituksia LSD algorithmien suunnitteluun sekä ehdotetaan sopivia toteutuskompromisseja käytännön langattomiin järjestelmiin. Haastavammat suorituskyky- ja latenssivaatimukset edellyttävät lisätutkimuksia toteutusarkkitehtuureihin ja toteutuksiin. Erityisesti rinnakkaisten resurssien käyttö ja liukuhihnatekniikka toteutusarkkitehtuureissa mahdollistavat optimaalisen kompromissin löytämisen toteutuksessa käytettyjen resurssien ja laskentanopeuden väliltä. Väitöskirjassa suunnitellaan tehokkaat arkkitehtuurit tutkituille LMMSE ja LSD algoritmeille ottaen huomioon niiden ominaisuudet. Väitöskirjassa tutkitaan algoritmien toteutusta VLSI tekniikalla ja pyritään saamaan realistinen arvio algoritmien kompleksisuudesta ja suorituskyvystä. Algoritmeille suunnitellut arkkitehtuurit on toteutettu sekä FPGA piirille että erillisenä toteutuksena ASIC teknologialla. Väitöskirjassa esitetään myös testilaitteistolla tehtyjä mittaustuloksia ja varmistetaan toteutettujen algoritmien suorituskyky.
34

Analyse structurale automatique des petites molécules organiques / Automatic structural analysis of small organic molecules

Plainchont, Bertrand 18 December 2012 (has links)
Ce mémoire traite du développement d'outils informatiques d'aide à l'analyse structurale des petites molécules organiques par Résonance Magnétique Nucléaire (RMN). Il comprend deux volets axés sur l'automatisation de tâches auxquelles les chimistes des laboratoires de synthèse organique ou d'isolement de substances naturelles sont confrontés au quotidien, à savoir l'élucidation et la vérification de structure. Le premier volet concerne des améliorations apportées au logiciel de génération de structure LSD (Logic for Structure Determination). Ce logiciel est basé sur l'interprétation des corrélations des spectres de RMN 2D pour la détermination de structures complètement ou partiellement inconnues. Les progrès récents ont pour but d'augmenter la diversité des molécules analysables et d'améliorer le traitement des corrélations ainsi que la présentation des résultats. L'intégration de LSD avec la base de données SISTEMAT permet de bénéficier de la source d'information supplémentaire que constitue la valeur des déplacements chimiques. Cet avantage se traduit par un filtrage des solutions en fonction d'éléments de sous-structure sélectionnés dans une collection de squelettes de produits naturels. Le second volet présente le développement du logiciel CASA (Computer-Aided Spectral Assignment) dont le rôle est de réaliser une vérification automatique de structure par l'attribution des résonances. Il s'appuie sur des contraintes issues des spectres de RMN 2D et sur un module de prédiction des déplacements chimiques 13C. / This thesis deals with the development of computational tools for structural analysis of small organic molecules by Nuclear Magnetic Resonance (NMR). It consists of two parts that focus on the automation of tasks that chemists working in the fields of organic synthesis or natural substance isolation daily face, namely structure elucidation and verification. The first part reports improvements of the structure generation software LSD (Logic for Structure Determination). This software is designed for the determination of completely or partially unknown structures from the interpretation of 2D NMR correlation spectra. The present work aims to increase the diversity of the molecules that can be analyzed and to improve the processing of correlation data as well as the presentation of results. The integration of LSD with the SISTEMAT database introduces chemical shifts values as an additional information source. It allows the chemist to sort the possible solutions of a problem according to the presence of known natural product skeletons. The second part presents the development of the CASA (Computer-Aided Spectral Assignment) software as a tool for automatic structure assignment. It jointly makes use of constraints from 2D NMR spectra and from the matching between experimental and predicted 13C chemical shifts.
35

Vybrané aspekty a vzorce užívání lysohlávek a LSD u pacientů v PN v Dobřanech / Selected aspects and patterns of magic mushrooms and LSD use at patients at the psychiatric hospital in Dobřany

Strejčková, Vanda January 2016 (has links)
Backrounds: Former Czechoslovakia was known for the studies of halucinogens and their use in cure in psychiatric care. In the last couple of years LSD and other halucinogens have been coming to renaissance again. Nowadays researchers are returning to these theories and they are trying to follow these studies. In the Czech Republic according to studies conducted in 2002, 2004 and 2008, there was an increase in the use of all drugs in general population. For example there was an increase of 2.5 times more of use between 2002 and 2008 (from 2.2% to 5.6%). The same increase showed the use of halucinogen mushrooms that were monitored only in 2004 and 2008. Objectives: The main point of the whole research was to map aspects and patterns of the use of magic mushrooms and LSD and monitor the outcome on these patients, also monitor their physical and psychiatric problems. The study monitors how each person deals with their use and solutions that can be used in prevention with patients especially among growing population are tried to be found. Methods and research group: The research was conducted in polystructured form of an interview with 34 patients in hospital in Dobrany (34 men and 3 women) who had had at least one piece of experience with the use of magic mushrooms or LSD and were willing for the...
36

The Psychedelic Altered State of Consciousness : An Assessment of the Current Status of Psychedelic Research

Christersson, Emma January 2019 (has links)
Classic psychedelic substances, such as lysergic acid diethylamide and the active compound in magic mushrooms, psilocybin, are being studied again in a renaissance of psychedelic research. Psychedelic substances have profound effects on perception, emotion, and cognition, as well as the capacity to induce mystical-type experiences and ego-dissolution. Recent clinical studies indicate that these substances have positive effects on patient populations and healthy participants, both acutely and long-term. Neuroimaging studies show that psychedelics alter neural integration, by the disintegration of normally stable resting state networks, and increasing network connectivity between normally anticorrelated networks. This thesis will review the phenomenological characteristics of the psychedelic-induced altered state of consciousness, the therapeutic potential of the psychedelic-induced altered state of consciousness, and neuroimaging studies on the psychedelic state. Two theoretical accounts are compared on the brain basis of psychedelic-induced altered state of consciousness. From the recent research on psychedelics a novel theory of conscious states has evolved, the entropic brain theory. This theory will be compared to the integrated information theory, a well-established theory of consciousness within cognitive neuroscience.
37

Psychedelic psychiatry: LSD and post-World War II medical experimentation in Canada /

Dyck, Erika. Wright, David, January 2005 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: David Wright. Includes bibliographical references (leaves 272-306). Also available online.
38

Waste in Lean Software Development : A Root Cause Analysis / Waste in Lean Software Development : A Root Cause Analysis

Medidi, Prasadbabu January 2015 (has links)
Context: Removal of wastes is a crucial area in lean software development. It has been found that there was little evidence on root causes of wastes in lean software development. Root causes from the state of practice had not being investigated. Furthermore, relations between wastes were now successfully exposed through root cause identifications process. Objectives: The objective of this study was to perform an in-depth investigation to identify causes which lead to wastes in Lean software development process in the context of medium to large software development. To this end, researcher also identified relationships that exist between wastes. Methods: The researcher conducted Literature review to look for evidence on waste related activities offered in peer-reviewed literature. Furthermore, the author conducted seven semi-structured interviews and used Grounded Theory method for both literature and interview data analysis. Results: The researcher identified three categories of factors of wastes. Namely, Technical, Non-technical and Global software product development. In the technical category, factors relating to different technical aspects to build a product such as required resource issues, solving complexity issues among others were identified. Similarly, factors relating to people knowledge, management issues as well as factors that bothered on communication, coordination and temporal distance were identified as non-technical and global software product development respectively. For all seven kinds of wastes the root causes were identified. / 0046734784551
39

Equalization and channel estimation algorithms and implementations for cellular MIMO-OFDM downlink

Ketonen, J. (Johanna) 17 June 2012 (has links)
Abstract The aim of the thesis is to develop algorithms and architectures to meet the high data rate, low complexity requirements of the future mobile communication systems. Algorithms, architectures and implementations for detection, channel estimation and interference mitigation in the multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) receivers are presented. The performance-complexity trade-offs in different receiver algorithms are studied and the results can be utilized in receiver design as well as in system design. Implementation of detectors for spatial multiplexing systems is considered first. The linear minimum mean squared error (LMMSE) and the K-best list sphere detector (LSD) are compared to the successive interference cancellation (SIC) detector. The SIC algorithm was found to perform worse than the K-best LSD when the MIMO channels are highly correlated. The performance difference diminishes when the correlation decreases. With feedback to the transmitter, the performance difference is even smaller, but the full rank transmissions still require a more complex detector. A reconfigurable receiver, using a simple or a more complex detector as the channel conditions change, would achieve the best performance while consuming the least amount of power in the receiver. The use of decision directed (DD) channel estimation is also studied. The 3GPP long term evolution (LTE) based pilot structure is used as a benchmark. The performance and complexity of the pilot symbol based least-squares (LS) channel estimator, the minimum mean square error (MMSE) filter and the DD space-alternating generalized expectation-maximization (SAGE) algorithm are studied. DD channel estimation and MMSE filtering improve the performance with high user velocities, where the pilot symbol density is not sufficient. With DD channel estimation, the pilot overhead can be reduced without any performance degradation by transmitting data instead of pilot symbols. Suppression of co-channel interference in the MIMO-OFDM receiver is finally considered. The interference and noise spatial covariance matrix is used in data detection and channel estimation. Interference mitigation is applied for linear and nonlinear detectors. An algorithm to adapt the accuracy of the matrix decomposition and the use of interference suppression is proposed. The adaptive algorithm performs well in all interference scenarios and the power consumption of the receiver can be reduced. / Tiivistelmä Tämän väitöskirjatyön tavoitteena on kehittää vastaanotinalgoritmeja ja -arkkitehtuureja, jotka toteuttavat tulevaisuuden langattomien tietoliikennejärjestelmien suuren datanopeuden ja pienen kompleksisuuden tavoitteet. Työssä esitellään algoritmeja, arkkitehtuureja ja toteutuksia ilmaisuun, kanavaestimointiin ja häiriönvaimennukseen monitulo-monilähtötekniikkaa (multiple-input multiple-output, MIMO) ja ortogonaalista taajuusjakokanavointia (orthogonal frequency division multiplexing, OFDM) yhdistäviin vastaanottimiin. Algoritmeista saatavaa suorituskykyhyötyä verrataan vaadittavaan toteutuksen monimutkaisuuteen. Työn tuloksia voidaan hyödyntää sekä vastaanotin- että järjestelmäsuunnittelussa. Lineaarista pienimmän keskineliövirheen (minimum mean square error, MMSE) ilmaisinta ja listapalloilmaisinta (list sphere detector, LSD) verrataan peräkkäiseen häiriönpoistoilmaisimeen (successive interference cancellation, SIC). SIC-ilmaisimella on huonompi suorituskyky kuin LSD-ilmaisimella radiokanavan ollessa korreloitunut. Korrelaation pienentyessä myös ilmaisimien suorituskykyero pienenee. Erot suorituskyvyissä ovat vähäisiä silloinkin, jos järjestelmässä on takaisinkytkentäkanava lähettimelle. Tällöinkin korkean signaali-kohinasuhteen olosuhteissa LSD-ilmaisimet mahdollistavat tilakanavoidun, suuren datanopeuden tiedonsiirron. Radiokanavan muuttuessa uudelleenkonfiguroitava vastaanotin toisi virransäästömahdollisuuden vaihtelemalla kompleksisen ja yksinkertaisen ilmaisimen välillä. Kanavaestimointialgoritmeja ja niiden toteutuksia vertaillaan käyttämällä lähtökohtana nykyisen mobiilin tiedonsiirtostandardin viitesignaalimallia. Tutkittavat algoritmit perustuvat pienimmän neliösumman (least squares, LS) ja pienimmän keskineliövirheen menetelmään, sekä päätöstakaisinkytkettyyn (decision directed, DD) kanavaestimointialgoritmiin. DD-kanavaestimaattori ja MMSE-suodatin parantavat vastaanottimen suorituskykyä korkeissa käyttäjän nopeuksissa, joissa viitesignaaleiden tiheys ei ole riittävä. DD-kanavaestimoinnilla datanopeutta voidaan nostaa viitesignaaleiden määrää laskemalla vaikuttamatta suorituskykyyn. Työssä tarkastellaan myös saman kanavan häiriön vaimennusta. Häiriöstä ja kohinasta koostuvaa kovarianssimatriisia käytetään ilmaisuun ja kanavaestimointiin. Työssä esitetään adaptiivinen algoritmi matriisihajoitelman tarkkuuden ja häiriön vaimennuksen säätämiseen. Algoritmi mahdollistaa hyvän suorituskyvyn kaikissa häiriötilanteissa vähentäen samalla virrankulutusta.
40

Orthographic Similarity and False Recognition for Unfamiliar Words

Perrotte, Jeffrey 01 December 2015 (has links)
There is evidence of false recognition (FR) driven by orthographic similarities within languages (Lambert, Chang, & Lin, 2001; Raser, 1972) and some evidence that FR crosses languages (Parra, 2013). No study has investigated whether FR based on orthographic similarities occurs for unknown words in an unknown language. This study aimed to answer this question. It further explored whether FR based on orthographic similarities is more likely in a known (English) than in an unknown (Spanish) language. Forty-six English monolinguals participated. They studied 50 English and 50 Spanish words during a study phase. A recognition test was given immediately after the study phase. It consisted of 40 Spanish and 40 English words. It included list words (i.e., words presented at study); homographs (i.e., words not presented at study, orthographically similar to words presented at study); and unrelated words (i.e., words not presented at study, not orthographically similar to words presented at study). The LSD post-hoc test showed significant results supporting the hypothesis that false recognition based on orthographic similarities occurs for words in a known language (English) and in an unknown language (Spanish). Further evidence was provided by the LSD post-hoc test supporting the hypothesis that false recognition based on orthographic similarities was more likely to occur in a known language than an unknown language. Results provided evidence that the meaning and orthographic form are used when information is encoded thereby influencing recognition decisions. Furthermore, these results emphasize the significance of orthography when information is encoded and retrieved.

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