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1
Blumenthal, Cecilia, and Elin Jacobsson. "Fonologi hos svenska förskolebarn med typisk utveckling." Thesis, Linköpings universitet, Logopedi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93376.
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The present study aims to investigate the phonological development of typically developing monolingual Swedish speaking children aged three to four years. The result could be used in the standardization of a new phonological test material for clinical speech and language pathology assessments. One-hundred and thirty four children aged three and four years (73 girls and 61 boys) were assessed with the new material. The children were tested in kindergartens in three communities in southeastern Sweden. Their assessments were audio recorded, transcribed phonetically and analyzed with Percentage Phonemes Correct (PPC) and Percentage of Words Correct (PWC). An analysis of speech error patterns of substitutions of phonemes, reduction of consonant clusters and word structural deviations was conducted. The data recorded from the children were divided and analyzed in four semi-annual intervals and two annual intervals. The result shows a clear developmental trend with children in the older age group having a higher PPC and PWC than the younger children. Significant differences were found between the groups in annual intervals. Significant differences could only be demonstrated between the youngest age group and the other groups at semi-annual intervals. No significant gender differences were observed. Most of the errors of individual phonemes and consonant clusters among children in all age groups were distortions rather than substitutions, but the younger children simplified consonant clusters more often.
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Berglund, Josefin, and Kaisa Hasselquist. "Fonologi hos svenska 5- och 6-åringar med typisk språkutveckling : Referensmaterial till det fonologiska testmaterialet LINUS." Thesis, Linköpings universitet, Logopedi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-109068.
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A new phonological test, LINUS, for Swedish-speaking children between the ages of three and seven, has been developed at the speech and language pathology department at Linköping University. The aim of the present study was to create a reference manual for the long version of the new test. The participants in the present study were children between the ages of five to seven in a medium-sized municipality in the Northern part of Kalmar County, Sweden. In total, 124 native Swedish-speaking children (58 girls and 66 boys) with typical language development participated. The children were divided into two age groups, 5;0-5;11;31 and 6;0-6;11;31 years. The collected data was analysed with respect to acquisition of phonemes and word structure processes. Percentage of correctly produced words (PWC), consonants (PCC) and vowels (PVC) were calculated.All phonemes, except /s/, were established in both age groups. The phoneme /s/ was found to be either substituted or distorted. Among the 5-year old children /s/ was established for 84%, substitutions of /s/ were found in 7% and distortions were found in 23%. Among the 6-year old children /s/ was established for 88%. Substitutions of /s/ were found in 3% and distortions in 16% of the 6-year old children. The phoneme /r/ proved to be a borderline case for acquisition in the younger age group (91%). The most common word structure process in both groups was assimilation. A significant difference between the two age groups was found for assimilation (p=0,022), with lower occurrence in the older group. Two-consonant clusters (CC) and three-consonant clusters (CCC) were not frequently reduced, although it was found that CC-clusters were reduced more frequently than CCC-clusters. Both the age groups had high percentages of correctly produced words, consonants and vowels. The analysis revealed the following results: PWC for 5-years olds was 93% and 6-years olds 97%. PCC for 5-year olds was 98% and for 6-year olds 99%. PVC for both age groups was 100%. An age difference was shown for PWC, but not for the other measures. No gender differences were found.Ett nytt fonologiskt testmaterial, LINUS, är framtaget för svensktalande barn. I föreliggande studie har referensmaterial till den långa versionen av det nya testet insamlats bland barn 5-7 år i en mellanstor kommun i norra Kalmar län. Totalt deltog 124 barn (58 flickor och 66 pojkar) med svenska som modersmål och typisk språkutveckling. Barnen delades upp i två åldersintervall, 5;0-5;11;31 och 6;0-6;11;31 år. Det insamlade materialet analyserades avseende etablering av fonem och konsonantkombinationer, samt förekomst av ordstrukturprocesser. Andelsmått för korrekt uttalade ord (PWC), konsonanter (PCC) och vokaler (PVC) beräknades.Samtliga fonem, utom /s/, var etablerade i båda åldersgrupperna. Fonemet /s/ realiserades med substitutioner eller kvalitativt marginella avvikelser (KMA). I 5-årsgruppen var /s/ etablerat för 84% av deltagarna. Bland 5-åringarna förekom substitutioner av /s/ hos 7% och KMA förekom hos 23%. I 6-årsgruppen var /s/ etablerat till 88%, och det förekom substitutioner hos 3% av 6-åringarna, och KMA förekom hos 16%. Fonemet /r/ visade sig vara ett gränsfall avseende etablering för den yngre åldersgruppen (91%). Den vanligaste ordstrukturprocessen för båda grupperna var assimilationer. Signifikanta skillnader mellan de två åldersgrupperna återfanns avseende assimilationer, p=0,022. Förekomsten av assimilationer minskade med stigande ålder. Tvåkonsonantskombinationer (CC) och trekonsonantskombinationer (CCC) visade sig ej vara påverkade av förenklingar i någon större grad. Dock visade sig CC-kombinationer vara mer utsatta för förenklingar än CCC-kombinationer. Båda åldersgrupperna hade höga andelar korrekt uttalade ord, konsonanter och vokaler. De två grupperna fick följande resultat: PWC för 5-åringar var 93% och 6-åringar 97%. PCC var 98% respektive 99% för grupperna. PVC var 100% för båda åldersgrupperna. Åldersskillnader kunde ses för PWC, dock inte för de andra måtten. Inga könsskillnader noterades.
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Andersson, Ingrid, and Andrea Stenlund. "Stereotypiska könsmönster inom revisionsbranschen : En bildanalys av PwC." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79195.
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Clinton, Jonathan. "Fem vuxnas perspektiv på filosofiska samtal i skolan." Thesis, Södertörns högskola, Institutionen för kultur och lärande, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-22941.
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Previous research on philosophy for children in schools has almost exclusively focused on how it is perceived by students. The aim of this study is to focus on how it is perceived by five teachers and other adults involved in implementing philosophy for children in schools, in total four teachers participated and one adult who worked with implementing took part in the study. The theoretical background is composed of Olga Dysthes view that knowledge is not only constructed but that the object that one intends to gain knowledge of has to be interacted with and how she applies this view dialogues in the classroom. The study was conducted by interviewing the participants. The results found that the teachers saw philosophy for children as something more than a tool to work with questions that were important to students, they were also viewed as a way to work with language and building solidarity within the class. Some of the informants also expressed views that they were certain that the discussions would end in the students aquiring the values that the school represented but that if this was not the case they would have to step in to steer the conversation towards these values. The study also found ambiguity towards the role of teachers as fascilitators of these discussions. There was a concern that the teacher as fascilitator could result in the students either returning to normal classroom behaviour or that they would alter what they said to fit what they were expecting the teacher to hold as the right answer. However the positive sides to having a teacher fascilitator was that these would know the class better and better be able to establish an environment that is suited for a philosophical discussion.
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Mayiwar, Lewend, Gino Nano, and Glenn Donnestenn. "The Process of Retaining Knowledge: A Case Study of PwC." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-32917.
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Tracking and capturing tacit knowledge of individuals in a way that can be leveraged by a company is one of the fastest growing challenges in knowledge management. In addition, the dynamism and changing role of today’s economy brings with it many challenges left with organizations to face. As employee turnover is caused by many uncontrollable factors, this paper aims at exploring how organizations can reduce its negative impact by creating and retaining critical knowledge, rather than suggesting ways in which employee turnover can be reduced.
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Grudeborn, Johanna, and Hanna Rigvald. "Intensiv behandling för två förskolebarn med fonologiska svårigheter." Thesis, Linköpings universitet, Institutionen för klinisk och experimentell medicin, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148744.
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Children with phonological disorder are at risk of developing reading and writing impairments. Phonological difficulties may also influence a child’s social interaction and it is for this reason that effective treatment of phonological disorder is important. One factor that may influence treatment efficacy, is treatment intensity. There has been little research done in Sweden, on the effects of intensity of phonological intervention. Further research into phonological intervention is therefore needed to determine which treatment intensity is the most effective. The aim of this study is to evaluate the possible effects of intensive treatment of two preschool children with phonological disorder. The research questions focus on the nature of the possible effects of phonological treatment and if they lead to generalization, and whether caregivers notice any changes in their children’s speech. A single-subject design was used with three baseline measurements, followed by treatment and two follow up measurements. The treatment was given three times a week over the course of three weeks, and every treatment session lasted for approximately 40 minutes. The results of the baseline and follow ups were calculated with Percentage Consonants Correct (PCC), Percentage Words Correct (PWC), and the percentage of manner of articulation correct. Both participants displayed improvements between the baseline and the second follow up, in all the measurements. Changes could be seen in the target phonemes both in new positions and in new words, but also in untrained phonemes. The caregivers of both participants experienced an improvement in their children's speech. How the estimated intensity affected the results is unclear. However, the results indicated that intensive treatment led to generalization and that it showed effect. Thus, the results of the present study could have clinical relevance.Förskolebarn med fonologiska svårigheter riskerar att få läs- och skrivsvårigheter i skolåldern och påverkan på det sociala samspelet. Det är därför viktigt med effektiv fonologisk intervention, som kan påverkas av intensiteten. Det finns sparsamt med svenska studier om intensitetens påverkan vid fonologisk intervention. Föreliggande studie syftar till att utvärdera eventuell effekt av intensiv behandling hos två förskolebarn med fonologiska svårigheter. Frågeställningarna innefattar hur den eventuella effekten av fonologisk behandling ser ut, om den leder till generalisering, samt om vårdnadshavarna upplever någon förändring. Studien hade en single-subject design med tre baslinjemätningar och två uppföljande mätningar. Fonemtestet LINköpingsUnderSökningen (LINUS) användes vid samtliga mätningar. Behandlingen genomfördes vid nio tillfällen, tre gånger i veckan i tre veckor. Varje behandlingstillfälle var cirka 40 minuter långt. Resultatet av LINUS-testningen beräknades med Percentage Consonants Correct (PCC), Percentage Words Correct (PWC) och andel korrekt artikulationssätt och analyserades även kvalitativt. Resultaten jämfördes mellan de olika mätningarna. Båda deltagarna uppvisade förbättringar för samtliga mått mellan baslinjemätningarna och den sista uppföljande mätningen. Förändringar kunde ses av tränade ljud till nya ord och positioner samt av ljud som inte tränades i behandling. Vårdnadshavarna till de deltagande barnen upplevde att deras barns tal hade förbättrats efter behandlingen. Det är svårt att uttala sig om vilken inverkan den uppskattade intensiteten hade på behandlingsutgången. Resultatet indikerar dock att intensiv behandling hade effekt och att den ledde till generalisering, och skulle således kunna vara till nytta i klinisk verksamhet.
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Seyom, Sara. "Inre- och yttre motivation med SDT : En studie av PwC Uppsala." Thesis, Högskolan i Gävle, Avdelningen för ekonomi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-11606.
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Muñoz, Faúndez Mariana, and Figueroa Juan Ignacio Lerdon. "Implementación de UEN en el área de consultoría y asesoría empresarial en PWC : gobiernos corporativos." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/146045.
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TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN ADMINISTRACIÓNMariana Muñoz Faúndez [Parte I], Juan Ignacio Lerdon Figueroa [Parte II]
evidencia a nivel internacional ha demostrado que la adopción de mejores prácticas de gobierno corporativo dentro de las organizaciones está fuertemente relacionada con su trascendencia y crecimiento sostenido.i A partir de lo anterior, este plan de negocios está relacionado a los cambios y requerimientos actuales del mercado sobre el tema de GC, donde se observa el impacto en Chile de tres compañías que fueron líderes en sus industria; como La Polar (Chile, 2011), Inverlink (Chile, 2003) y Enron (EE.UU., 2001). La experiencia internacional indica que las buenas prácticas de GC fortalecen los órganos de dirección y control de las empresas, al tiempo que definen reglas entre los actores, e incrementan el nivel de transparencia y rendición de cuentas frente a grupos de interésii. Por tanto, PwC Chile detecta una oportunidad de negocio para ampliar su portafolio de servicios, donde propone incorporar una UEN asociada a la asesoría y consultoría de GC, que pretende contribuir a los clientes en la formulación del mejoramiento de la eficiencia en sus procesos a nivel corporativo, ayudar al desarrollo de una gestión de riesgos que permitan prevenir y/o mitigar situaciones, e incentivar a los miembros del GC para se capaciten en estos temas. Todo lo anterior, con la propuesta promover las buenas prácticas en los GC de las principales empresas del país. También, mediante este servicio se busca que las empresas obtengan resultados positivos sin descuidar la sustentabilidad, la perdurabilidad y velando por producir externalidades positivas sobre el entorno. Es así, como se ha realizado la evaluación financiera en UF asociada a la implementación de la UEN, proyecto que entrega un valor presente neto (VPN) ascendente a UF295.930, con una TIR de 137% y tasa de descuento de 7,87%. Esto es atractivo para el inversionista, ya que los retornos esperados del proyecto superan los costos y otros desembolsos para llevar a cabo el mismo. Cabe mencionar, que la UEN ofrece este servicio de GC integrado, siendo pionero dentro de las 4 grandes firmas auditoras, lo que está relacionado de manera directa con la estrategia de PwC de ser líder en la oferta a clientes y en la calidad entregada en cada uno de los servicios diferenciados
2018-12-01
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Laver, John Poynton, and n/a. "The Public Works Committee : an anlysis and evaluation of the Australian Commonwealth's Parliamentary Standing Committee on Public Works." University of Canberra. Management, 1990. http://erl.canberra.edu.au./public/adt-AUC20060816.155712.
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This dissertation analyses the origin, purposes, nature, operation
and achievements of the Commonwealth's Parliamentary Standing
Committee on Public Works (Public Works Committee - PWC),
and assesses its utility to parliament. The PWC originated in
1913 as a permanent committee of parliamentarians established to
examine government proposals for public works, and report on
them to parliament. Its purpose is to provide detailed data on
works proposals in order to allow informed voting. In the process
parliament also achieves a degree of control over government
- ministers and public servants. Unlike most parliamentary
audit of government expenditure, the PWC scrutinises proposals
before works are built. It is a joint, statutory, scrutiny
committee.
The proper role for parliamentary committees in general is the
checking of government, through influence, criticism, scrutiny,
and publicity. The PWC is assessed against this role through an
analysis of its legislation and operation, and interviews with
involved parliamentarians and bureaucrats. Criteria used include
adequacy of evidence obtained, precision and clarity of
reports, and degree of influence on government and acceptance of
recommendations. In these terms the PWC has little effect in
controlling policy making by the executive government - cabinet
and ministers. Moreover, specific amendment of its act together
with the consequential effects of nominally unrelated
legislation, have reduced the scope of Committee activities to
an estimated less than half of all Commonwealth public works.
This trend is continuing under current policies of corporatising
departmental activities and excluding the resulting statutory
corporations from PWC examination. These moves prevent parliament
playing its proper role in the governance of the country.
However, within the ambit of its powers, the PWC generally rates
highly against the above criteria, and exerts a significant
degree of parliamentary control over government administration -
the public service - in the implementation of public works.
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Dahl, Maria, and Kristina Hellberg. "Kvinnor i karriären : en jämförande studie om hur det är att som kvinna arbeta på revisionsbyrå i Nederländerna respektive Sverige." Thesis, Högskolan i Borås, Institutionen Handels- och IT-högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18590.
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Då uppsatsförfattarna tillbringade en termin som utbytesstudenter på Hogeschool Inholland i Rotterdam, Nederländerna uppstod ett intresse för kulturella skillnader mellan länder. Författarna, som i grund och botten anser att Nederländerna och Sverige är två relativt lika länder, stötte med jämna mellanrum på diverse kommentarer gällande kvinnors situation i arbetslivet, vilket gjorde att uppmärksamhet riktades mot det området. Uppsatsen syftar med det här som bakgrund till att utveckla de tankegångar som väcktes under tiden i Nederländerna och svara på frågan:”Hur skiljer sig upplevelsen av att vara kvinna på revisionsbyrå i Sverige respektive Nederländerna?”Diskussionen kring frågeställningen förs med sex intervjuer som underlag, tre genomförda i Nederländerna och tre i Sverige på revisionsbyrån Öhrlings PricewaterhouseCoopers. Utgångspunkten för de samtal som fördes med respondenterna ligger i Hofstedes teorier om kulturella dimensioner. Det insamlade empiriska materialet har bearbetats narrativt och sammanställts i en fiktiv mailkonversation.Syftet med uppsatsen är att lyfta fram tankar och attityder kring frågeställningen och locka till reflektion hos läsaren. Processen har präglats av ett hermeneutiskt förhållningssätt och en abduktiv ansats. En kvalitativ metod genomsyrar studien och datainsamlingen skedde genom kvalitativa intervjuer, vilket bidragit till att det är respondenters egna åsikter och attityder kring frågeställningen som framförs.Tre områden har visat på skillnader länderna emellan. Det första området gäller den så kallade ”up-or-out” kulturen, vilken innebär att avancera eller lämna företaget. Den här kulturen har stor påverkan på medarbetarna i Nederländerna, men kan inte sägas förekomma i Sverige. I Nederländerna är det inte accepterat att stanna på en viss hierarkisk nivå, utan den anställde måste hela tiden sträva uppåt. I Sverige är det godtaget att välja att bli kvar på en viss nivå och inte ha avancemang som främsta karriärsmål.Det andra området handlar om hur mycket tid som läggs ner på arbetsrelaterade aktiviteter utöver direkta arbetsuppgifter. Överlag verkar ett heltidsarbete på revisionsbyrå innebära fler timmar än de 40 timmar per vecka som är praxis. Utöver det här ansåg respondenterna i Nederländerna att det var viktigt för karriären att spendera en del av sin fritid på arbetsrelaterade aktiviteter. Syftet med det är att skaffa sig ett brett nätverk, vilket är viktigt för möjligheten till snabbt avancemang.Det tredje området rör möjligheten att kombinera karriär och familjebildande. Under forskningsprocessen har det framkommit att i allmänhet anser inte de kvinnor vi talat med att deras kön påverkar det dagliga arbete något nämnvärt. Ett område skiljer dock länderna åt. Kvinnorna i Nederländerna tvingas, på grund av regelverk och attityder kring föräldraledighet, i många fall välja mellan karriär och familjebildande. I Sverige upplevs det ej som om valet att bilda familj utesluter möjligheten att göra karriär.Det är författarnas förhoppning att uppsatsen ska locka till reflektion och eftertanke hos läsaren. Vi hoppas även att vi genom vår framställning av det empiriska materialet kan bidra till ett alternativt synsätt på frågeställningen.Uppsatsnivå: D
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Lundström, Emelie, and Martyna Nasilowska. "Revisionens digitalisering : en kvalitativ studie om hur digitaliseringen har påverkat revisionsprocessen och revisorsrollen." Thesis, Högskolan Kristianstad, Fakulteten för ekonomi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-21093.
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Dagens studier visar på att revisionsbranschen förändras i takt med digitaliseringens framfart, vilket gör det därför omöjligt för revisionsbyråer att välja bort digitaliseringen. Tidigare forskning påvisar att revisionsbranschen är en av de branscher som blivit mest påverkad av digitaliseringens framfart, eftersom flera arbetsuppgifter har ersatts av den nya tekniken. Syftet med studien har varit att undersöka hur revisionsprocessen samt revisorsrollen har påverkats av den allt mer digitaliserade arbetsmiljön. För att uppnå studiens syfte har en kvalitativ metod använts där fem medarbetare på PwC har intervjuats. Empirin analyseras sedan med hjälp av studiens insamlade teori i syfte att besvara studiens två frågeställningar. Därefter har en innehållsanalys utförts där funna samband ur den insamlade empirin ställts mot studiens teori. Studiens resultat påvisar att digitaliseringen redan har bidragit till förändringar i revisionsprocessens olika faser. Vidare har digitaliseringen påverkat revisorsrollen där revisorn har fått en mer betydande roll för revisionen. Fortsättningsvis påvisar den insamlade empirin att digitaliseringen har resulterat i ett effektivare arbetssätt samt att trovärdigheten på revisionen har ökat. Avslutningsvis förutspår digitaliseringens utveckling att fortsätta och dessutom påverka värdeskapandet i revisionsbranschen. Vidare tyder teorin och empirin på att det kommer skapas mervärde genom att revisorerna således kommer fokusera på att skapa värde för kunden. Slutligen förväntas digitaliseringen påverka efterfrågan på revisionen och vilka egenskaper som behövs hos en revisor, vilket är sociala och tekniska egenskaper samt bedömningsförmågan.There are studies that indicate big changes concerning audit industries as the digitalization continues to develop. It is known that the audit offices can no longer ignore the fact that digitalization has taken an important role in our society. Previous research shows that the audit industry is one of the many industries that has been affected by digitalization, this because many of the tasks have been replaced by new technology. The purpose of this study has been to investigate how digitalization has affected the audit industry. In this report, a qualitative method has been used where five employees by PwC have been interviewed. The empiricism that was collected during the interviews was analyzed through the use of the theories presented with the aim of answering the study’s two main questions. Subsequently, an analysis of the content was performed where correlations found by the collected empiricism were compared to the theories of the study. The result of the study was that the digitalization has already contributed to changes in the phases of the audit process and the auditor role. Furthermore, the digitalization has resulted in a more efficient way and increased the credibility of the audit. The development of digitalization has been predicted to continue and also affect value creation in the audit industry. The collected theory and empiricism show that the auditors focusing more on creating value for the customers. Finally, digitalization is expected to have an impact on the demand for the audit and its qualities.
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Lange, André De Bastiani. "Retificador PFC monofásico PWM bridgeless três-níveis de alto desempenho." Florianópolis, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/100858.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia ElétricaMade available in DSpace on 2013-06-25T23:20:04Z (GMT). No. of bitstreams: 1 307896.pdf: 8014354 bytes, checksum: e7f5c5f26cf0e245f5bbdc82d9fe7865 (MD5)
Este trabalho apresenta uma nova topologia de retificador monofásico com fator de potência e rendimento elevados, com o objetivo de adaptar-se aos requisitos de sistemas de conversão modernos. O conversor se caracteriza por integrar as etapas de retificação e conversão CC-CC em um único estágio e por operar com três níveis de tensão para o controle da corrente de entrada. A estrutura possibilita a redução das perdas em condução e de comutação, bem como a redução do volume de dispositivos magnéticos. Uma operação eficiente do retificador é obtida com uma técnica de modulação adequada, também foco deste trabalho. Duas técnicas de controle para o retificador foram analisadas e implementadas em um controlador digital de sinais de baixo custo. Uma análise de estabilidade é apresentada para a técnica de autocontrole de corrente considerando-se os efeitos dos atrasos de transporte da implementação digital. Um novo controlador adaptativo e metodologia de projeto são propostos para permitir a operação do conversor em ampla faixa de variação de carga utilizando esta técnica. A verificação experimental é realizada através de um protótipo de 3 kW desenvolvido em laboratório, para o qual se utilizou uma metodologia de projeto que minimiza o volume de material magnético utilizado no indutor boost.
This work presents a novel single-phase rectifier topology with high power factor and high efficiency, aiming to fulfil modern conversion systems requirements. This converter is characterized by integrating the rectifying and DC-DC conversion stages into a single stage and operates with three voltage levels for controlling the input current. The topology enables low conduction and commutation losses and reduced volume of magnetic devices. Efficient rectifier operation is achieved with a suitable modulation technique, which is also within the focus of this work. Two control techniques for the rectifier have been analysed and implemented in a low-cost digital signal controller. A stability analysis is presented for the current self-control technique considering the effects of the transport delays found in the digital implementation. A new adaptive compensator and design method are proposed to allow the converter to operate with wide load variation range using this technique. Experimental verification is performed with a 3 kW labprototype employing a boost inductor optimized design that minimizes magnetic material volume.
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Gustafsson, Johanna, and Karolin Ryberg. "Redovisning till verkligt värde av förvaltningsfastigheter : En rättvisande bild?" Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Företagsekonomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15092.
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Syfte: Syftet är att analysera hur redovisning till verkligt värde av förvaltningsfastigheter påverkar den rättvisande bilden av ett företag. Bakgrund: Värdering av anläggningstillgångar till anskaffningsvärde har länge varit vägledande i Europa. Trots att denna metod är tillförlitlig anses den inte ge en rättvisande bild av företaget. Detta kan istället värdering till verkligt värde anses göra då detta sätt att redovisa skapar relevans i redovisningen. Denna redovisningsmetod är dock förknippad med minskad tillförlitlighet, stora svängningar i resultat och för sin konjunkturförstärkande effekt. Redovisning till verkligt värde har fastighetsbranschen använt sig av sedan införandet av IAS/IFRS 2005. Branschen kännetecknas av frekventa och starka svängningar i värdet på förvaltningsfastigheterna, vilka helst ska värderas till verkligt värde. Detta föranleder frågan hur rättvisande fastigheternas värden egentligen är. Metod: Analysen av problemområdet har skett genom en kvalitativ metod och en deduktiv ansats. Befintlig teori har jämförts med empiriskt material som har insamlats via intervjuer. Intervjuerna har varit icke-standardiserade och utförts med fyra auktoriserade revisorer från de fyra största revisionsbolagen i Sverige och en värderingsexpert. Slutsats: Verkligt värde av förvaltningsfastigheter medför positiva effekter till den rättvisande bilden främst genom att bidra med relevans och jämförbarhet. Med aktieägare som primära användare av den finansiella informationen kan verkligt värde även antas vara begriplig. Värderingsmetoden har däremot en negativ påverkan på den rättvisande bilden genom omfattande brister i tillförlitlighet. Relevansen i redovisning till verkligt värde kan dock kompensera för dessa brister. Detta torde innebära att redovisning till verkligt värde bidrar till en rättvisande bild av ett företag.Purpose: The purpose is to analyse how fair value accounting of investment property affect the true and fair view of a company. Background: Valuing fixed assets at historical cost has for a long time been the preferred choice in Europe. Although this method is reliable it is not considered to contribute to a true and fair view of a company. This can however fair value accounting (FVA) be considered to do as it creates relevance in the financial reports. On the other hand, FVA can also be associated with reduced reliability, volatility in profits and procyclicality. FVA was first adopted by the investment property industry in 2005 when IAS/IFRS was imposed in Sweden. This industry is characterised by its volatile property values, which are preferably to be valued at fair value. This raises the question of whether the values of the investment properties really are fair? Method: In order to answer the purpose a qualitative method was used. The deductive approach enabled a comparison between existing theories and empirical material gathered through in-depth interviews. The interviews were non- standardised and conducted with four authorised auditors from the four largest auditing firms, and a fair value expert. Conclusion: FVA of investment property contributes to the true and fair view of a company in terms of relevance and comparability. Since shareholders are the primary users of financial information FVA can also be considered understandable. The valuation method does however have a negative affect on the true and fair view due to considerable deficiencies in reliability. If relevance can be considered to make up for these deficiencies, it can be argued that FVA contributes to the true and fair view of a company.
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CALLAPINO, German Garabito. "Empilhamento sísmico pela composição de ondas planas." Universidade Federal do Pará, 1997. http://repositorio.ufpa.br/jspui/handle/2011/5784.
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DAAD - Serviço Alemão de Intercâmbio Acadêmico / Deutscher Akademischer Austauschdiens
No presente trabalho de tese é apresentada uma nova técnica de empilhamento de dados sísmicos para a obtenção da seção de incidência normal ou afastamento fonte-receptor nulo, aplicável em meios bidimensionais com variações laterais de velocidade. Esta nova técnica denominada Empilhamento Sísmico pela Composição de Ondas Planas (empilhamento PWC) foi desenvolvida tomando como base os conceitos físicos e matemáticos da decomposição do campo de ondas em ondas planas. Este trabalho pode ser dividido em três partes: Uma primeira parte, onde se apresenta uma revisão da técnica de empilhamento sísmico convencional e do processo de decomposição do campo de ondas produzido a partir de fontes pontuais em suas correspondentes ondas planas. Na segunda parte, é apresentada a formulação matemática e o procedimento de aplicação do método de empilhamento sísmico pela composição de ondas planas. Na terceira parte se apresenta a aplicação desta nova técnica de empilhamento na serie de dados Marmousi e uma analise sobre a atenuação de ruído. A formulação matemática desta nova técnica de empilhamento sísmico foi desenvolvida com base na teoria do espalhamento aplicado a ondas sísmicas sob a restrição do modelo de aproximação de Born. Nesse sentido, inicialmente se apresenta a determinação da solução da equação de onda caustica para a configuração com afastamento fonte-receptor finito, que posteriormente é reduzido para a configuração de afastamento fonte-receptor nulo. Por outra parte, com base nessas soluções, a expressão matemática deste novo processo de empilhamento sísmico é resolvida dentro do contexto do modelo de aproximação de Born. Verificou-se que as soluções encontradas por ambos procedimentos, isto é, por meio da solução da equação da onda e pelo processo de empilhamento proposto, são iguais, mostrando-se assim que o processo de empilhamento pela composição de ondas planas produz uma seção com afastamento fonte-receptor nulo. Esta nova técnica de empilhamento basicamente consiste na aplicação de uma dupla decomposição do campo de ondas em onda planas por meio da aplicação de dois empilhamentos oblíquos (slant stack), isto é um ao longo do arranjo das fontes e outro ao longo do arranjo dos detectores; seguido pelo processo de composição das ondas planas por meio do empilhamento obliquo inverso. Portanto, com base nestas operações e com a ajuda de um exemplo de aplicação nos dados gerados a partir de um modelo simples, são descritos os fundamentos e o procedimento de aplicação (ou algoritmo) desta nova técnica de obtenção da seção de afastamento nulo. Como exemplo de aplicação do empilhamento PWC em dados correspondentes a um meio com variações laterais de velocidade, foi aplicado nos dados Marmousi gerados segundo a técnica de cobertura múltipla a partir de um modelo que representa uma situação geológica real. Por comparação da seção resultante com a similar produzida pelo método de empilhamento convencional, observa-se que a seção de afastamento nulo desta nova técnica apresenta melhor definição e continuidade dos reflectores, como também uma melhor caracterização da ocorrência de difrações. Por último, da atenuação de ruído aleatório realizada nos mesmos dados, observa-se que esta técnica de empilhamento também produz uma atenuação do ruído presente no sinal, a qual implica um aumento na relação sinal ruído.
In this thesis we present a new seismic data stacking method called Plane Wave Composition (PWC). This method, applicable in a bidimensional medium with lateral velocity gradients, is developed on the basis of physical and mathematical concepts on the plane wave decomposition of spherical wave fields. In the initial part of this work, we present a review on the conventional stacking method and on plane wave decomposition of the point-source seismograms. The stacking by plane wave composition is a method which produce a normal incidence (or zero offset) section by the application of the following main processes: A double plane wave decomposition, achieved by a slant stack along the shot array and another slant stack along the receiver array, followed by a plane wave composition achieved by an inverse slant stack. The PWC stacking method is theoretically formulated here on the basis of the scattering theory applied to seismic waves, within the constraint of the Born approximation. Initially, starting with the acoustic wave equation, for a finite source-receiver configuration, a solution for the direct single scatter (Born) model is derived. That result is reduced for the coincident source-receiver (zero offset) configuration. Afterward, the mathematical expression of PWC stacking method is solved replacing the observed data function by the scattered field obtained by the Born approximation. For most clarity, the algorithm to obtain the zero offset seismic section by the PWC stacking method is described by applying it to the data corresponding to a simple model. A successful application is performed using the Marmousi seismic data set, corresponding to a geological complex model. Finally, in the same data set, a noise analysis shows that this method increase the signal-noise ratio in the seismic trace. Thus, it has been showed that the PWC stacking method is an efficient alternative to process seismic data of complex models.
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Thériault, Mathieu. "Étude de l'interaction de ERR[alpha] et de ses corégulateurs dans le carcinome colorectal." Mémoire, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/6364.
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Le récepteur relié au récepteur à l'estrogène alpha (ERR?) est un récepteur orphelin de la superfamille des récepteurs nucléaires impliqué dans la régulation du métabolisme énergétique. II cause l'expression de gènes impliqués dans les différentes voies métaboliques et peut ainsi augmenter le potentiel de production d'énergie des cellules. Fidèle à son état d'orphelin, l'activité de ERR? ne semble pas être régulée via la liaison d'un ligand, mais plutôt via la présence des corégulateurs. Les corégulateurs sont des protéines ayant pour fonction d'assister ou de nuire à l'action des récepteurs nucléaires et autres facteurs de transcription dans l'expression de leurs gènes cibles. L'étude de l'interaction entre ERR? et ses corégulateurs s'avère donc être incontournable pour la compréhension de son rôle dans les divers processus où il est impliqué et dans les pathologies auxquelles il est associé comme le cancer qui est un dérèglement cellulaire causé par des altérations génétiques, et est caractérisé par une prolifération incontrôlée de cellules au sein d'un organisme. Pour qu'une cellule devienne cancéreuse, elle doit acquérir des mutations précises au niveau du génome causant des modifications dans la régulation de différents processus. Un de ces processus est le métabolisme énergétique. Le but de ma maîtrise était d'identifier et d'étudier les corégulateurs de ERR? (PGC-1?, PGC-1? et PRC) et leur modulation de gènes cibles de ERR? dans le contexte du métabolisme énergétique du cancer. L'expression de ERR? et des trois membres de la famille PGC-1 a été mesurée par qPCR sur des tissus colorectaux sains et cancéreux appropriés. L'expression de ERR? ne semble pas significativement différente suivant l'apparition de la pathologie, alors que l'expression des coactivateurs PGC1-? et PGC-1? s'avère moins élevée dans les tissus cancéreux par rapport aux tissus sains. L'expression de PRC est plus grande dans le cancer colorectal. Ces résultats suggèrent que PRC pourrait posséder un rôle, exclusif à sa famille, dans le carcinome colorectal. Afin de trouver de nouveaux corégulateurs de ERR?, nous avons procédé à une expérience de double hybride sur levure qui a permis d'identifier 6 nouveaux partenaires d'interactions du récepteur : La leucine aminopeptidase 3 (LAP3), le synaptic nuclear envelope protein 1 (SYNE1 /nesprinl ), le proteasome macropain 26S subunit ATPase (PSMC5), la DEAD box polypeptide 1 (DDXI), le ring finger protein 2 (RNF2/Ring2) et l'interferon-related developmental regulator IFRD1. Leurs fonctions connues peuvent toutes être associées à l'action de ERR?, soit en régulant sa dégradation ou son activité. En particulier, nos résultats pour 1FRD1 montrent que son expression est supérieure dans la presque totalité des cancers colorectaux étudiés par rapport aux tissus sains adjacents. On peut ainsi supposer que cette protéine possède une fonction encourageant la carcinogenèse. De plus, des essais luciférases ont montré qu'IFRD1 augmente l'activité du récepteur nucléaire ERR?. Le partenariat entre ERR? et IFRD I pourrait donc être pertinent lors de la carcinogenèse colorectale. ERR?, PGC-1, PRC, IFRD1.
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Palmgren, Erik. "Den Gropkeramiska kulturens framträdande : en kritisk analys gällande tre av de främsta teorierna kring den Gropkeramiska kulturens framträdande i Nordeuropa." Thesis, Högskolan på Gotland, Institutionen för humaniora och samhällsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1850.
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In this essay the author has chosen to analyze the similarities and differences between some of the northern Europe’s late Mesolithic and Neolithic cultures. The research is of a processual standpoint and the information is mainly gathered from secondary sources as well as ethnological studies. The material collected has been analyzed in both a processual and a post-processual manner to most accurately study the foundations of the three primary theories describing the Pitted Ware Culture’s origin. During the course of the study the author also found a possible fourth alternative, and the possibility of exogamy as a factor in the emerge of the Pitted Ware Culture has also been questioned. This work has prompted for a rigorous collection of information to be able to properly present all theories strong and weak points, without bias for any theory. The conclusion of these studies is that it is very hard to pinpoint exactly what it is that has given the Pitted Ware Culture its typical cultural traits, although a possible sequence of events has been presented in this text.
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Durif, Charlotte. "Elaboration de membranes non-oxydes de type SiBC pour la maîtrise de la contamination dans les réacteurs à eau pressurisée." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT179/document.
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Ce travail de thèse a porté sur le développement de membranes céramiques pour la filtration de colloïdes issus de la corrosion dans le circuit primaire des REP. La voie des polymères précéramiques a été mise en œuvre par la synthèse d’un polyborocarbosilane (PBC) à partir d’allylhydridopolycarbosilane conduisant à une céramique de type SiBC. Des billes de PMMA mono disperses d’une taille de 1,5 et 0,3 µm ont été préparées pour servir d’agent porogène pour créer une porosité contrôlée. Des objets micro-cellulaires 3D de forme circulaire ont été élaborés par pressage uni-axial avec ajout de billes de PMMA commercial pour servir de support macroporeux. Une étude de cristallinité à haute température (> 1000 °C) a été réalisée, montrant son influence sur la stabilité du matériau. La couche sélective a été préparée par dip-coating à partir de différentes formulations de barbotine contenant du PBC et les billes de PMMA élaborées. La stabilité physico-chimique des supports micro-cellulaires a été étudiée grâce à des essais de vieillissement en micro-autoclave en milieu primaire simulé. La résistance à la filtration a été testée grâce à un essai sur un dispositif de filtration connecté à un moyen d’essai de laboratoire permettant de simuler les conditions des REPThis work has been focused on the development of ceramic membranes for the filtration of colloids resulting from corrosion in the primary loop of PWR. SiBC ceramics were synthesized by the preceramic polymers route from a polyborocarbosilane (PBC) obtained from allylhydridopolycarbosilane. Single-dispersed PMMA beads with a size of 1.5 and 0.3 μm were prepared to be used as a porogen agent to lead to a controlled porosity of the selective layer. 3D micro-cellular objects with a circular shape were developed by uni-axial pressing with the addition of commercial PMMA beads to serve as a macroporous support. A crystallinity study at high temperature (> 1000 ° C) was carried out showing its influence on the stability of the material. The selective layer was prepared by dip-coating from various slurry formulations containing PBC and the prepared PMMA beads. The chemical and physical stability of the microcellular supports was studied by ageing tests in a simulated primary water chemistry. The filtration resistance was tested by means of tests on a filtration device connected to a laboratory loop which simulates the conditions of the PWRs
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Plammootil, Suma Mary. "Herstellung und Etablierung von 4-Hydroxytamoxifen aktivierbaren PKC[alpha]- [PKC alpha]-, PKC[beta]1- [PKC beta1] und PKCd--Fusionsproteinen [PKC delta-Fusionsproteinen]." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971703302.
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Santos, Junior Luciano Pereira dos. "Uma fonte chaveada de 50kW com corre??o de fator de pot?ncia para alimenta??o de uma tocha de plasma Indutiva utilizando t?cnicas de controle digital." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15308.
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Previous issue date: 2009-04-17This work deals with the development of an experimental study on a power supply of high frequency that provides the toch plasmica to be implemented in PLASPETRO project, which consists of two static converters developed by using Insulated Gate Bipolar Transistor (IGBT). The drivers used to control these keys are triggered by Digital Signal Processor (DSP) through optical fibers to reduce problems with electromagnetic interference (EMI). The first stage consists of a pre-regulator in the form of an AC to DC converter with three-phase boost power factor correction which is the main theme of this work, while the second is the source of high frequency itself. A series-resonant inverter consists of four (4) cell inverters operating in a frequency around 115 kHz each one in soft switching mode, alternating itself to supply the load (plasma torch) an alternating current with a frequency of 450 kHz. The first stage has the function of providing the series-resonant inverter a DC voltage, with the value controlled from the power supply provided by the electrical system of the utility, and correct the power factor of the system as a whole. This level of DC bus voltage at the output of the first stage will be used to control the power transferred by the inverter to the load, and it may vary from 550 VDC to a maximum of 800 VDC. To control the voltage level of DC bus driver used a proportional integral (PI) controller and to achieve the unity power factor it was used two other proportional integral currents controllers. Computational simulations were performed to assist in sizing and forecasting performance. All the control and communications needed to stage supervisory were implemented on a DSP
O presente trabalho trata do desenvolvimento de um estudo experimental sobre uma fonte de alimenta??o de alta freq??ncia que alimentar? a tocha pl?smica a ser implementada no projeto PLASPETRO, o qual consta de dois conversores est?ticos desenvolvidos com o uso de transistores - Insulated Gate Bipolar Transistor (IGBT). Os drivers utilizados no controle dessas chaves s?o acionados por um controlador de sinal digital - Digital Signal Processor (DSP) atrav?s de fibras ?pticas a fim de reduzir problemas com interfer?ncia eletromagn?tica - Electromagnetic interference (EMI). O primeiro consiste de um est?gio pr?-regulador na forma de um conversor CA-CC boost trif?sico com corre??o de fator de pot?ncia, tema principal deste trabalho, enquanto o segundo consiste na fonte de alta frequ?ncia propriamente dita. Um inversor s?rie-ressonante composto por 4 (quatro) c?lulas inversoras operando a uma frequ?ncia de cerca de 115 kHz cada, em modo de comuta??o suave, alternando-se para fornecer ? carga (tocha de plasma) uma corrente alternada com uma frequ?ncia de 450 kHz. O primeiro est?gio tem a fun??o de fornecer ao inversor s?rie-ressonante uma tens?o CC de valor controlado a partir da rede de alimenta??o disponibilizada pelo sistema el?trico da concession?ria, al?m de corrigir o fator de pot?ncia do sistema como um todo. Esse n?vel CC de tens?o no barramento de sa?da do primeiro est?gio ser? utilizado para o controle da pot?ncia transferida pelo inversor ? carga, podendo variar desde 550Vcc at? um valor m?ximo de 800Vcc. Para controlar o n?vel de tens?o do barramento CC utilizou-se um controlador Proporcional Integral (PI) e para atingir o fator de pot?ncia unit?rio utilizou-se dois outros PIs para controle das correntes em referencial estacion?rio. Simula??es computacionais foram realizadas para auxiliar no dimensionamento e previs?o de performance. Todo o controle e comunica??es necess?rias ao est?gio supervis?rio foram implementadas em um DSP
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Seman, Vladimír. "Analýza PPC systémů při různých PPC kampaních." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-15459.
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Pay per click (PPC) advertising over the past few years has gained importance and companies invest larger amounts of money into it. There are more PPC systems in the market from which to choose for advertising. Which PPC system is appropriate to use for a specific campaign? This thesis consists of four chapters (excluding introduction and conclusion). The first chapter clarifies terms, talks about the basic characteristics of the subject and gives an idea of the importance of the topic (position of pay per click in the market of internet advertising). The second chapter characterizes three PPC systems (and their principles) which the author considers to be the most important in the Slovak market. The third chapter is important for the characterisation of different types of PPC campaigns. In it the author used his own classification of PPC campaigns. Two case studies are analysed in the fourth chapter. According to them an evaluation of the suitability of selected PPC systems is made (using induction method). The first three chapters are based on an analysis of available literature, the fourth part on the author's own experiences.
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Liu, Kefeng. "E-PIC." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-125876.
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For many off-road drive lovers, planning a journey to Tibet is an ultimate dream. However, the eco-system there is quite sensitive and fragile. In this project I try to design a sustainable vehicle that could make us enjoy an expedition to Tibet while protecting such precious environment. Research about future trends, about the environmental conditions, about emerging powertrain technologies and the Jeep brand helped me to establish my design concept. Package study, ideation sketches and clay modelling were used to develop both styling and functionality aspects of the vehicle. Digital modelling supported the fabrication of a quarter scale model. Storytelling was used to explain the concept and the situations that Jeep E-pic drivers could meet during their expedition. The result is a self-powered all-terrain vehicle designed to carry two occupants and their expedition gear and equipped with various tools to handle eventual maintenance and rescue situations.
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Plo, Isabelle. "Activation des voies anti-apoptotiques par les ligands de mort et les médicaments antitumoraux." Toulouse 3, 2002. http://www.theses.fr/2002TOU30048.
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Velazquez, Alberto. "Microstructure and thermal stability of PVC and chemically modified PVC." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74243.
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This thesis describes a study of the effect of microstructure on the thermal stability of poly(vinyl chloride), PVC, vinyl chloride-ethylene, VC-E, and vinyl chloride-propylene, VC-P, copolymers obtained by chemical modification of PVC. The VC-E copolymers, with an ethylene content between 1.1 and 21 mole %, are random copolymers with approximately the same degree of polymerization as the original PVC. A decrease in the number of defect sites is observed with extent of reaction. Concomitantly, the syndiotacticity increases. The VC-P copolymers, with propylene content of ca. 0.1%, also have less labile chlorines than the homopolymer since these react preferentially.The thermal stability of solid state samples was studied, at temperatures between 150 and 190$ sp circ$C under a nitrogen atmosphere, using a conductimetric method to measure evolved HCl. The thermal stability of the modified samples is improved relative to that of the initial homopolymers. For the VC-E copolymers, a linear relationship is observed between the rates of degradation and the number of labile chlorines, total double bonds and the degree of syndiotacticity. The role of syndiotacticity on the thermal degradation behavior is confirmed in results obtained with two unmodified PVC samples, with a similar number of defect sites but different syndiotacticity. The more syndiotactic resin shows a higher thermal stability. The average polyene sequence length is independent of the ethylene concentration. Thus, the ethylene units do not interfere in the development of polyene sequences.
The VC-P copolymers also show improved thermal stability as compared to that of PVC. However, the improvement is less than that of the VC-E copolymers, due to a lower extent of substitution of labile sites.
PVC previously saturated with HCl shows a markedly increased rate of degradation reflecting the autocatalytic role of HCl. For the PVC coated samples, a decrease in the degradation rates with decreasing PVC film thickness is observed due to more efficient removal of HCl. The PVC mixtures with Chromosorb W or silica gel exhibit a decrease in the dehydrochlorination rate constants with decreasing PVC content. The inert substrate acts as a diluent and avoids agglomeration of the samples and thus facilitates the removal of HCl.
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Gaßmann, Luise [Verfasser], Rüdiger [Akademischer Betreuer] Görtz, Rüdiger [Gutachter] Görtz, and Lukas [Gutachter] Pfeifer. "Scherwellenelastographie (Acoustic radiation force impulse) bei autoimmunen und cholestatischen Lebererkrankungen (AIH, PBC, PSC, Overlap-Syndrom) / Luise Gaßmann ; Gutachter: Rüdiger Görtz, Lukas Pfeifer ; Betreuer: Rüdiger Görtz." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1213979285/34.
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Bjärhusen, Jonas, and Jan-Olof Martinsson. "PWM Effekt Audioförstärkare." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2637.
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The purpose with the report is to show that it is possible to design a class-D amplifier, using a programmable FPGA mounted on a developing card from Xess and a H-bridge. The FPGA was programmed in VHDL which is the language the software from Xilinx use to implement a logical function into the FPGA The logical function corresponds to a modeling of the music signal and the modeling can be described as a comparator which compare the music signal with a triangle wave and as a out signal produce a pulse width modulated (PWM) signal. The report is also a review and evaluating of two different modulating technologies, AD- modeling and BD-modeling. A detailed part about how the H-bridge was designed and how it works. The result of this project is a working audio amplifier to a significant lower price than the products in todays market.
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MELLO, RODRIGO SILVA. "PLC CHANNEL MODELLING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6687@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROO crescente interesse na utilização das redes de distribuição de energia elétrica como uma alternativa para o fornecimento de serviços de telecomunicações, tem motivado a pesquisa e o desenvolvimento de sistemas capazes de superar as características hostis deste ambiente como canal de comunicação. Com esta finalidade, este trabalho procura estimar o comportamento da rede PLC através da modelagem da função de transferência do canal, para a faixa de freqüência de 300 kHz a 30 MHz, por meio de um conjunto de parâmetros, os quais podem ser deduzidos da medição da resposta em freqüência. Dois modelos são apresentados para descrever a resposta em freqüência complexa de típicos canais power line, cobrindo todos os efeitos que os caracterizam, tais como o efeito de propagação por multipercursos causado pelas inúmeras reflexões nas junções da rede e o desvanecimento seletivo em freqüência. Os experimentos revelam que estes modelos apresentam todas as características principais da rede PLC podendo representar ferramentas úteis e efetivas na prática, oferecendo a possibilidade de realizar pesquisas para diferentes topologias de rede, a fim de estudar seu impacto no sistema de comunicação pela rede de energia elétrica. Além disso, propõem-se modelos de ajuste da função de transferência do canal a dados empíricos pelo método dos mínimos quadrados.
The crescent interest on the utilization of the low voltage power distribution grid as an alternative to provide services of telecommunication has motivated the systems development able to surpass the hostile characteristics of this environment as a communication channel. Therefore, this work seek to estimate the behavior of PLC network (Power Line Communication) through the modelling of the channel transfer function, to the range of 300 kHz to 30 MHz, by means of a set of parameters, which can be derived from the measure of the frequency response. Two models are presented to describe the complex frequency response of power line channels, covering all effects that define them, for example, the multipaths propagation generated by uncountable reflections on the network connections and selective fading in the frequency. The results of experiments show that these models present the most important characteristics of PLC network, representing useful and effective tools in the practice, offering the possibility to do researches to different network topologies, in order to study the impact of these effects on the PLC system. Moreover, they`re proposed channel transfer function adjustment models through empiric data and the least square method.
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Novák, Pavel. "Úzkopásmový PLC modem." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242170.
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The theses is focused on the use of PLC technology. The aim of the thesis is creating device which communicates in a narrowband transmission frequency band. Transmission of communication between plc elements runs through the low voltage distribution network. The frequency and phase modulations are used in order to change the character of data signal. Transmitter and receiver parameters are subjects to the CENELEC standard. The theses gives more attention to the area of hardware build communication element rather than the area of programming.
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Ferreira, Fernando Hilton Teixeira. "Automa??o residencial microcontrolada para transmiss?o de dados via rede el?trica." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br/handle/123456789/20019.
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Este trabalho trata da especifica??o e da implementa??o de um protocolo para controlar a comunica??o entre dois microcontroladores (PICs), utilizando como meio de transmiss?o a rede el?trica, tornando a comunica??o mais segura e economicamente vi?vel. O Protocolo foi implementado em linguagem de programa??o C, tendo como refer?ncia alguns protocolos desenvolvidos para uso automobil?stico. Foi implementado tamb?m um circuito para testar a comunica??o PLC e o Protocolo.
This work deals with the specification and the implementation of a protocol for controlling communication between two programmable interface microcontrollers (PIC), using power line communication (PLC), making communication more secure and economically viable. The Protocol was implemented in C language, with reference to some protocols developed for automotive use. A circuit to test the communication between the PLC and the Protocol was also implemented.
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Searle, J. R. "Titanium dioxide pigment photocatalysed degradation of PVC and plasticised PVC coatings." Thesis, Swansea University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638788.
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Due to its ubiquitous presence in paints of all colours, titanium dioxide represents the primary pigment used in Organically Coated Steel (OCS) for construction applications. However the semi-conducting nature of TiO2 translates into a possibility of inducing photodegradation when exposed to Ultra Violet (UV) radiation such as that present in sunlight. Initial research concentrated on developing a test procedure of the photoactivity of these pigments within a PVC binder. Model coatings, using pigments of known performance, have been tested to evaluate the success of this rapid test technique and excellent correlation has been shown. Building on this, Chapter 4 details a unique cell that has been designed, constructed and tested resulting in a more versatile testing environment. This cell has been used to examine the photostability of 4 commercially available pigments while present within a standard emulsion paint binder. Chapters 5 and 6 detail work performed on Plasticised PVC paint films and the resultant effects this has on the kinetics of photodegradation as monitored via the evolution of CO2. Also incorporated into this design is the ability to identify and quantify volatile organic components that are evolved during the degradation process, thus providing information regarding the photodegradation mechanism occurring within the film. It has been found that in these model films, the addition of plasticiser increases the rate of photogenerated CO2 and also produces volatile components that can be directly related to the parent plasticiser molecule. There is some evidence to suggest that for certain plasticisers, a sacrificial protection mechanism is at work, resulting in increased CO2 evolution but decreased attack on the binder matrix. Finally in Chapter 7, a number of complimentary techniques are employed to assess the effect that TiO2 photocatalysed PVC degradation has on the underlying substrate material. The techniques include electrochemical impedance spectroscopy (EIS), electro-generated chemiluminescence (ECL) and 3-D scanning vibrating electrode technique (3-D SVET). Photodegradation leads to porosity development in coatings and eventual through coating penetrative defects lead to corrosion.
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Skrášek, Tomáš. "Úzkopásmová PLC komunikace se standardy G3-PLC, PRIME a IEEE-1901.2." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-220388.
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Diploma thesis is about narrowband PLC communication standards. The theoretical part describes details of all available OFDM standards including G3-PLC, PRIME, IEEE-1901.2 and G.hnem. The practical part deals with PRIME and G3-PLC standards. In this part is also compared OFDM technology with system of single carrier frequency in environment with real interferences. The last part describes developement of two firmwares for PLC modems Texas Instruments TMDSPLCKIT-V3, which allow UART communication and remote data collection. The thesis also includes Windows application developed to display and save collected data.
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Buchwald, Theresa [Verfasser], Clemens [Akademischer Betreuer] Forster, Clemens [Gutachter] Forster, and Andreas [Gutachter] Kremer. "Untersuchung neuronaler Konnektivitäten von Patienten mit Cholangitis (PBC&PSC) bei chronischem Juckreiz – eine fMRT-Studie / Theresa Buchwald ; Gutachter: Clemens Forster, Andreas Kremer ; Betreuer: Clemens Forster." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2021. http://d-nb.info/1238358268/34.
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Nylander, Karl, and Wallin Erik Trulsson. "Skiftet Mot PWA Inom Applikationsutveckling : En analys av PWA vs. native applikation." Thesis, Malmö universitet, Institutionen för datavetenskap och medieteknik (DVMT), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-43169.
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With mobile usage on the rise developers are more than ever faced with the issue of developing for multiple platforms. With Google's introduction of Progressive Web Applications (PWA) it is possible to build app-like web applications that can run on any platform. This study aims to investigate if PWA is mature enough to replace an already developed native iOS application. Specifically it aims to investigate if a PWA can achieve the same functionality and security as a native application, as well as what technologies are needed to do so. To verify this question an iOS application called iHug developed by a software company called Cloud Enablers was used as a reference point. With this reference a Minimum Viable Product (MVP) copy was developed as a PWA to verify that the functionality could be achieved. This PWA was not intended to replace the existing native application, but instead coexist with it. That means that the PWA must be able to communicate with the original application. In addition an investigation was done to see what measures needed to be taken to achieve security. The results showed that the same functionality was achievable, as was the security. Even though the results are promising, due to the native application not being developed with a PWA in mind there was a lot of extra work that had to be done to replicate certain functionalities and SDK choices. On this basis, while it is certainly possible to achieve the same functionality it is much harder to do so when the counterpart was not developed to be able to communicate with a PWA.
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Rosa, Luca. "Studio di un alimentatore a singolo stadio per lampade a scarica di gas." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3525/.
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Hu, Jian 1971. "Deadbeat contolled PWM converter." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30251.
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The thesis has evaluated the suitability of Digital Deadbeat Control of the Sinusoidal Pulse Width Modulation-Voltage Source Converter (SPWM-VSC) for electric power utility applications.The Digital Deadbeat Controlled SPWM-VSC operates as a current controller where short circuit faults are not destructive. In addition, it eliminates the L-R mode at the ac terminals of the SPWM-VSC. The thesis considers methods to immunize the control from system and parameter uncertainties. A novel closed-loop Digital Deadbeat Control has been proposed. A Phase Lock Loop (PLL) suitable for this application is developed.
Together with the PLL, the Digital Deadbeat Controlled SPWM-VSC has been shown to be capable of (1) independent control of current Id and Iq, (2) near sinusoidal current waveforms, (3) broad operation frequency range.
Digital simulation is used in the thesis to prove the performance of the Digital Deadbeat Controlled SPWM-VSC.
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Selden, Suzanne M. "PHC : unravelling a maze." University of Sydney, 2009. http://hdl.handle.net/2123/5976.
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Doctor of Philosophy(PhD)The thesis explores the complexities of primary health care in a setting characterised as being both isolated and remote, and in the process identifies factors critical for developing successful PHC programs in such settings and more broadly. The four questions underpinning the study are 1) is a PHC approach relevant to the chosen small remote Australian community; 2) to what extent was a PHC approach being implemented; 3) what are the barriers and enablers to developing and implementing a PHC approach; and 4) what are the crucial factors for PHC programs in similar communities. The first chapter provides the background to the study, beginning with the range of descriptions of primary health care and the many themes needed to understand how it plays out in a small community. The Menindee community and some of the local health service players are introduced. Chapter Two explores complexity theory and complex adaptive systems and its relevance to organisations and managing change, particularly in complex environments. Chapter Three examines the evolution of primary health care, its philosophy, principles and elements as both a model of health care and of development. Chapter Four addresses social determinants, the life course and the long-term effects of inequity, before considering current factors that impact on health and health services. These include the beginning and end of the life course and those in the ‘middle’ where the effects of the obesity and diabetes epidemics are being played out at a younger age. The chapter concludes by noting common themes across the three chapters. Chapter Five describes the research design and methods. A case study using mixed methods was chosen and the theoretical framework provides an exploration of complexity and transdisciplinarity. What changed during the course of the study, questions of scope and its limitations are stated. Chapter Six is a quantitative analysis of the study community, which examines community demographics, the life course, a summary of adult and child health, and service use. These enable an understanding of the community profile, its uniqueness and its similarity to other communities that might benefit from a comprehensive PHC approach. The questions to be explored in the qualitative phase are identified. Chapter Seven is a qualitative study of the community in the midst of change. An individual interview guide approach was used and representatives from the community, local and regional health service providers were interviewed. Chapter Eight provides a synthesis of the two studies as they address themes from the complexity, PHC and social inequity literature. Five themes had particular significance to the study community: social determinants and Indigenous health; community size, resilience and change; chronic disease programs and prevention; vulnerable groups; and a complex adaptive systems perspective. The second section answers the four study questions. The thesis concludes with a discussion of PHC rhetoric and reality, the relevance of the study and its limitations, and issues requiring further research when considering primary health care in smaller communities.
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Hu, Jian. "Deadbeat controlled PWM converter." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0032/MQ64227.pdf.
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Vess, Lora Elizabeth. "The politics of PVC /." Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2007. http://hdl.handle.net/1794/6195.
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Thesis (Ph. D.)--University of Oregon, 2007.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 252-277). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.
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Büttner, Rene. "PTC Mathcad Prime 3.1." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-172536.
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Simmler, Urs. "PTC Creo Simulate 3.0." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-171761.
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葉錦添 and Kam-tim Ip. "Professional services in PRC." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31265674.
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江垂燊 and Shui-sun Kong. "Building superhighways in PRC." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31267981.
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Goldberg, Paul W. "PAC-learning geometrical figures." Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/10918.
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The thesis studies the following problem: given a set of geometrical figures (such as planar polygons), each one labelled according to whether or not it resembles some 'ideal' figure, find a good approximation to that ideal figure which can be used to classify other figures in the same way. We work within the PAC learning model introduced by Valiant in 1984. Informally, the concepts under consideration are sets of polygons which resemble each other visually. A learning algorithm is given collections of members and non-members of a concept, and its task is to infer a criterion for membership which is consistent with the given examples and which can be used as an accurate classifier of further example polygons. In order to formalise the notion of a concept, we use metrics which measure the extent to which two polygons differ. A concept is assumed to be the set of polygons which are within some distance of some fixed central polygon. In the thesis we work most extensively with the Hausdorff metric. Using the Hausdorff metric we obtain NP-completeness results for several variants of the learning problem. In particular we show that it is hard to find a single geometrical figure which is close to the positive examples but not to the negative examples. This result holds under various assumptions about the specific geometrical figures under consideration. It also holds for several metrics other than the Hausdorff metric. Despite the NP-completeness results mentioned above we have found some encouraging positive results. In particular, we have discovered a general technique for prediction. (Prediction is a less demanding learning model than PAC learning. The goal is to find a polynomial-time algorithm which takes as input a sample of labelled examples and is then able to predict the status of further unlabelled examples in polynomial time).
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Wüst, Michael, and Steffen Förster. "PTC Mathcad Prime : Überblick." Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-142117.
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Zirakiza, Brice. "Forêts Aléatoires PAC-Bayésiennes." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/29815/29815.pdf.
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Dans ce mémoire de maîtrise, nous présentons dans un premier temps un algorithme
de l'état de l'art appelé Forêts aléatoires introduit par Léo Breiman. Cet algorithme
effectue un vote de majorité uniforme d'arbres de décision construits en utilisant l'algorithme
CART sans élagage. Par après, nous introduisons l'algorithme que nous avons
nommé SORF. L'algorithme SORF s'inspire de l'approche PAC-Bayes, qui pour minimiser
le risque du classificateur de Bayes, minimise le risque du classificateur de Gibbs
avec un régularisateur. Le risque du classificateur de Gibbs constitue en effet, une fonction
convexe bornant supérieurement le risque du classificateur de Bayes. Pour chercher
la distribution qui pourrait être optimale, l'algorithme SORF se réduit à être un simple
programme quadratique minimisant le risque quadratique de Gibbs pour chercher une
distribution Q sur les classificateurs de base qui sont des arbres de la forêt. Les résultasts
empiriques montrent que généralement SORF est presqu'aussi bien performant
que les forêts aléatoires, et que dans certains cas, il peut même mieux performer que
les forêts aléatoires.In this master's thesis, we present at first an algorithm of the state of the art called Random Forests introduced by Léo Breiman. This algorithm construct a uniformly weighted majority vote of decision trees built using the CART algorithm without pruning. Thereafter, we introduce an algorithm that we called SORF. The SORF algorithm is based on the PAC-Bayes approach, which in order to minimize the risk of Bayes classifier, minimizes the risk of the Gibbs classifier with a regularizer. The risk of Gibbs classifier is indeed a convex function which is an upper bound of the risk of Bayes classifier. To find the distribution that would be optimal, the SORF algorithm is reduced to being a simple quadratic program minimizing the quadratic risk of Gibbs classifier to seek a distribution Q of base classifiers which are trees of the forest. Empirical results show that generally SORF is almost as efficient as Random forests, and in some cases, it can even outperform Random forests.
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Björklund, Johan. "PLC Back-up system." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17701.
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The purpose of this bachelor thesis was to investigate the PLC systems used in ABBs breaker factory in Ludvika and to create a system specification suitable to be used in the procurement of a back-up solution for this workshop. This work involved information gathering from different sources, such as archives, physical installations and interviews of maintenance personnel and operators. The results included the requested system specification (in Swedish) including suggestions for pilot test installations and evaluations. The work also resulted in an extensive listing of all PLC systems with placement, typedesignations, expansion modules and other pertinent information. This information ismade available as a macro enabled multipage Microsoft Excel document. A summary and suggestions for follow up work is also included.
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Joss, Victoria. "Surface treatments of PVC." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398489.
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Kong, Shui-sun. "Building superhighways in PRC /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18873352.
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Ip, Kam-tim. "Professional services in PRC /." [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13497807.
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Renbi, Abdelghani. "Improved PWB test methodologies." Licentiate thesis, Luleå tekniska universitet, EISLAB, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18253.
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Printed Wiring Board (PWB) and Printed Circuit Board Assembly (PCBA) testing aims to ensure an error free board after the etching and the assembly processes. After the etching process, several types of errors might occur such as opens and bridges, which are already, showstoppers in Direct Current (DC) applications. Mouse bites, spurs and others such as weak traces, which can be problematic in Radio Frequency (RF) and high-speed signals applications. Loading expensive component on defective boards can be economically catastrophic especially for high volume production. The rule of ten which has been reported by the production experts says that the defect costs ten times when detected in the next testing phase. Bare board also needs to be tested for the characteristic impedance correctness due to the process variations and the compounding raw material tolerances that can cause characteristic impedance mismatches. Although testing the characteristic impedance is not in interest in some application, sampling the characteristic impedance for a specific design is one way to test the manufacturing process stability for better tuning, otherwise PWBs might differ from each other even within the same batch. In addition to the possibility of defective PWB, the assembly process is never perfect to achieve 100 % of PCBA yield due to the possible errors in the process steps such as paste application, pick and place operations and soldering process which might lead to bridges, opens, wrong or miss oriented components.For low volume production, flying probes test technology is cost efficient as compared to bed-of-nails. The performance of the flying probes system depends on the test algorithm, the mechanical speed and the number of probes. To reduce the initial and maintenance costs of the probing technology and to accelerate the test time, Paper A introduces a new indirect method to test PWB continuity and isolation testing using a single probe for testing both continuity and isolation at the same time. RF signal is injected into the trace under test, instead of a DC current. The phase shift between the incident and the reflected signals is measured as it carries the information about the correctness of the trace when compared with a reference value of the same trace in the correct board. The method shown an important capability for detecting PWB defects such as as opens, DC and RF bridges, exceeded and different width lines. The margin in the measurement between a defective and a correct board, which depends on the type of the defect, is about 7 % to 68 %. Applying this approach to PCBA testing led to significant margins between correct and defective interconnect. The test cases in paper C shown 40 % and 33 %. Moreover, this margin has been proven to be important even for short microstrip line, which intended to connect two typical IC pins. This technique is strongly recommended to be applied to PCBA testing where probing is feasible. The approach can be applied to the complete layout testing or to boost a test strategy whose test solutions are not covering 100 % of the possible defects.By applying this test solution to bed-of-nails equipment, 50 % of the probes will be reduced, on the other hand, for a given design with NI isolated traces and NA adjacent pairs, employing this solution to flying probes system with two probes, leads to the reduction of the number of tests from (NI+NA) tests to NI tests as isolation and continuity are performed in one go. Flying probes system involves mechanical movements, which dominate the test time, reducing the number of the mechanical movements increases dramatically the test throughput. On the other hand, this method is believed to be extremely fast to test the correctness of the characteristic impedance which is prone to variations due to the instability of the PWB manufacturing process, in the same time one could employ the method to evaluate the process stability by checking after each batch of PWBs. Paper B and D provide insight into the impact of the PWB manufacturing variations on the characteristic impedance. Moreover single probe approach is believed to have a good potential for Sequential Build-Up (SBU) interconnects testing where connections between component pads and the upper layers are often impossible to test with the current test technologies.Godkänd; 2012; 20121123 (abdren); LICENTIATSEMINARIUM Ämne: Industriell elektronik/Industrial Electronics Examinator: Professor Jerker Delsing, Institutionen för system- och rymdteknik, Luleå tekniska universitet Diskutant: Associate Professor Erik Larsson, Linköpings universitet Tid: Tisdag den 18 december 2012 kl 13.00 Plats: A1514, Luleå tekniska universitet
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Vess, Lora Elizabeth 1972. "The Politics of PVC." Thesis, University of Oregon, 2007. http://hdl.handle.net/1794/6195.
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xv, 277 p. A print copy of this title is available from the UO Libraries, under the call number: SCIENCE TP1180.V48 V46 2007This dissertation examines the political, scientific, social, environmental, and health debates surrounding the use of polyvinyl chloride (commonly called vinyl), a plastic many public health advocates and activists contend has a toxic lifecycle with deleterious human and ecological impacts at every stage. Using extensive documentary research and in-depth interviews, I answer a basic question: how and why have major stakeholders politicized PVC in recent decades? I find the strength of the anti-PVC movement lies largely in its broad based constituency: it includes professionals within the health care and green building industries, as well as labor unions and environmental health advocates. However, I raise critical questions about the movement's strategy of situating itself as a market-based movement where limited analysis is given to the greater environmental and health impacts of the health care and building industries as a whole.
Adviser: Gregory McLauchlan