24,962 research outputs found
The construction of Karen Karnak: The multi-author-function
This thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
Language Change and SA-OT: The case of sentential negation
Simulated Annealing for Optimality Theory (SA-OT) updates Optimality Theory by adding a model of performance to a theory of linguistic competence. Our aim is to show that SA-OT can contribute to language change simulations. Performance "errors" are considered to be one of the causes of variation and change. We have chosen to model the evolution of sentential negation (SN). The descriptive background adopts Jespersen's Cycle, according to which the evolution of sentential negation follows three main stages (1. pre-verbal, 2. discontinuous, and 3. post-verbal). Therefore, we advance a novel model for SN, based on SA-OT. It reproduces the three pure and the two observed mixed stages, whereas it correctly predicts the lack of an intermediate stage between 3 and 1. The success of the approach corroborates the computational, performance-based approach to the data. Finally, we employ the iterated learning paradigm to reproduce historical changes in a "simulated corpus study". This enterprise turns out to be more difficult than one would naively believe.Appeared open access as: Computational Linguistics in the Netherlands Journal (CLIN), vol. 1 (2011), pp. 21-40, and is available at http://www.clinjournal.org/sites/default/files/Lopopolo.pdfA. Lopopolo and Biró, T., “Language Change and SA-OT. The case of sentential negation”, Computational Linguistics in the Netherlands Journal, vol. 1, pp. 21-40, 2011.Peer Reviewe
Semiconductor diagnostics and monitoring of chemical reactions by SIMS method
Hmotnostná spektrometria sekundárnych iónov s analýzou doby letu (TOF-SIMS) patrí vďaka vysokej citlivosti na prvkové zloženie medzi významné metódy analýzy pevných povrchov. Táto práca demonštruje možnosti TOF-SIMS v troch odlišných oblastiach výskumu. Prvá časť práce sa zaoberá lokalizáciou defektov vysokonapäťových polovodičových súčiastok, ktorá je nevyhnutná k ich ďalšiemu skúmaniu metódou TOF-SIMS. Bola navrhnutá experimentálna zostava s riadiacim softvérom umožňujúca automatizované meranie záverného prúdu v rôznych miestach polovodičový súčiastok. Druhá časť práce sa zaoberá kvantifikáciou koncentrácie Mg dopantov v rôznych hĺbkach vzoriek AlGaN. Kvantifikácia je založená na metóde RSF a umožňuje charakterizáciu AlGaN heteroštruktúr určených na výrobu tranzistorov s vysokou elektrónovou mobilitou (HEMT) alebo na výrobu rôznych optoelektronických zariadení. Sada 12 AlGaN kalibračných vzoriek dopovaných Mg, určených na kvantifikáciu hĺbkových profilov, bola pripravená metódou iónovej implantácie. Posledná časť práce demonštruje možnosti metódy TOF-SIMS vo výskume heterogénnej katalýzy. Hlavným objektom nášho výskumu je dynamika oxidácie CO na oxid uhličitý na polykryštalickom povrchu platiny za tlakov vysokého vákua. V tejto práci prezentujem prvé TOF-SIMS pozorovanie časopriestorových vzorov v reálnom čase, ktoré vznikajú v dôsledku rôzneho pokrytia povrchu Pt reaktantmi. Výsledky TOF-SIMS experimentu boli porovnané s výsledkami podobného experiment v rastrovacom elektrónovom mikroskope (SEM)
Quantitative Analysis of Surface-Immobilized Protein by TOF-SIMS: Effects of Protein Orientation and Trehalose Additive
We demonstrate the effects of protein orientation and trehalose on a quantitative analysis of surface-immobilized proteins by using time-of-flight secondary ion mass spectrometry (TOF-SIMS). As our model protein, streptavidin (SA) was quantitatively immobilized on a solid surface at different configurations by random or oriented immobilization and subsequently treated with trehalose. The resulting surface was analyzed by using TOF-SIMS and surface plasmon resonance (SPR) spectroscopy, where the secondary ion spectra from SA were compared with the surface density of the protein. In the case of oriented immobilization, the ion peak intensities measured by TOF-SIMS were correlated well with the SPR data, regardless of the presence of trehalose. Alternatively, trehalose significantly increased correlation between TOF-SIMS and SPR data for the randomly immobilized SA. It is likely that a trehalose-treated surface is less vulnerable to denaturation, thus leading to a reliable quantification of surface-immobilized proteins by TOF-SIMS. Our results show that TOF-SIMS can be used for understanding biophysical states such as orientation and denaturation of surface-immobilized proteins as well as for quantifying proteins within the field of biosensors and biochips
Semiconductor diagnostics and monitoring of chemical reactions by SIMS method
Hmotnostná spektrometria sekundárnych iónov s analýzou doby letu (TOF-SIMS) patrí vďaka vysokej citlivosti na prvkové zloženie medzi významné metódy analýzy pevných povrchov. Táto práca demonštruje možnosti TOF-SIMS v troch odlišných oblastiach výskumu. Prvá časť práce sa zaoberá lokalizáciou defektov vysokonapäťových polovodičových súčiastok, ktorá je nevyhnutná k ich ďalšiemu skúmaniu metódou TOF-SIMS. Bola navrhnutá experimentálna zostava s riadiacim softvérom umožňujúca automatizované meranie záverného prúdu v rôznych miestach polovodičový súčiastok. Druhá časť práce sa zaoberá kvantifikáciou koncentrácie Mg dopantov v rôznych hĺbkach vzoriek AlGaN. Kvantifikácia je založená na metóde RSF a umožňuje charakterizáciu AlGaN heteroštruktúr určených na výrobu tranzistorov s vysokou elektrónovou mobilitou (HEMT) alebo na výrobu rôznych optoelektronických zariadení. Sada 12 AlGaN kalibračných vzoriek dopovaných Mg, určených na kvantifikáciu hĺbkových profilov, bola pripravená metódou iónovej implantácie. Posledná časť práce demonštruje možnosti metódy TOF-SIMS vo výskume heterogénnej katalýzy. Hlavným objektom nášho výskumu je dynamika oxidácie CO na oxid uhličitý na polykryštalickom povrchu platiny za tlakov vysokého vákua. V tejto práci prezentujem prvé TOF-SIMS pozorovanie časopriestorových vzorov v reálnom čase, ktoré vznikajú v dôsledku rôzneho pokrytia povrchu Pt reaktantmi. Výsledky TOF-SIMS experimentu boli porovnané s výsledkami podobného experiment v rastrovacom elektrónovom mikroskope (SEM).Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a powerful surface science technique with high sensitivity for elemental composition. This work demonstrates TOF-SIMS abilities in three different research areas. The first part deals with the localization of high voltage dies defects, which is necessary for their further characterization by the TOF-SIMS method. For this purpose, an experimental setup with control software allowing automated measurement of leakage current tests at various die locations was proposed. The second part deals with the quantification of Mg dopant depth profiles in various AlGaN samples. The quantification is based on the RSF method and allows the characterization of doped AlGaN heterostructures for high electron mobility transistors (HEMT) or various optoelectronic devices. A set of 12 Mg doped AlGaN calibration samples for quantification of depth profiles was prepared by the ion implantation technique. The last part demonstrates the abilities of the static TOF-SIMS method in heterogeneous catalysis research. Our primary research objective is the dynamics of catalytic carbon monoxide oxidation to carbon dioxide on platinum polycrystalline microstructures at high vacuum pressures. In this work, we present the first real-time observations of spatiotemporal patterns of varying surface coverages during distinct catalyst regimes. TOF-SIMS observations were correlated with analogous scanning electron microscopy (SEM) observations of gas-phase- and temperature-induced processes on Pt surfaces.
Carol Altman Bromberg, Nicholas Sims-Williams, Ursula Sims-Williams. Iranian and Zoroastrian Studies in Honor of Prods Oktor Skjærvø
Comme le rappelle à juste titre Ursula Sims-Williams dans son portrait amical en guise d’introduction (p. 1-4), le savant norvégien Prods Oktor Skjærvø, « Aga Khan Professor of Iranian Studies » à l’Université de Harvard, a été et continue d’être un chercheur prolifique. Par sa production scientifique, il couvre en outre une remarquable diversité de langues iraniennes dans la longue durée (iranien ancien, moyen et moderne), ainsi que de religions (zoroastrisme, manichéisme et judaïsme babylon..
Seasonal SIMS δ18O record in Astarte borealis from the Baltic Sea tracks a modern regime shift in the NAO
Introduction: Astarte borealis holds great potential as an archive of seasonal paleoclimate, especially due to its long lifespan (several decades to more than a century) and ubiquitous distribution across high northern latitudes. Furthermore, recent work demonstrates that the isotope geochemistry of the aragonite shell is a faithful proxy of environmental conditions. However, the exceedingly slow growth rates of A. borealis in some locations (<0.2mm/year) make it difficult to achieve seasonal resolution using standard micromilling techniques for conventional stable isotope analysis. Moreover, oxygen isotope (δ18O) records from species inhabiting brackish environments are notoriously difficult to use as paleoclimate archives because of the simultaneous variation in temperature and δ18Owater values. Methods: Here we use secondary ion mass spectrometry (SIMS) to microsample an A. borealis specimen from the southern Baltic Sea, yielding 451 SIMS δ18Oshell values at sub-monthly resolution. Results: SIMS δ18Oshell values exhibit a quasi-sinusoidal pattern with 24 local maxima and minima coinciding with 24 annual growth increments between March 1977 and the month before specimen collection in May 2001. Discussion: Age-modeled SIMS δ18Oshell values correlate significantly with both in situ temperature measured from shipborne CTD casts (r2 = 0.52, p<0.001) and sea surface temperature from the ORAS5-SST global reanalysis product for the Baltic Sea region (r2 = 0.42, p<0.001). We observe the strongest correlation between SIMS δ18Oshell values and salinity when both datasets are run through a 36-month LOWESS function (r2 = 0.71, p < 0.001). Similarly, we find that LOWESS-smoothed SIMS δ18Oshell values exhibit a moderate correlation with the LOWESS-smoothed North Atlantic Oscillation (NAO) Index (r2 = 0.46, p<0.001). Change point analysis supports that SIMS δ18Oshell values capture a well-documented regime shift in the NAO circa 1989. We hypothesize that the correlation between the SIMS δ18Oshell time series and the NAO is enhanced by the latter’s influence on the regional covariance of water temperature and δ18Owater values on interannual and longer timescales in the Baltic Sea. These results showcase the potential for SIMS δ18Oshell values in A. borealis shells to provide robust paleoclimate information regarding hydroclimate variability from seasonal to decadal timescales
Preparation of sample cross-sections and analysis by SIMS
Táto práca sa zaoberá možnosťami štúdia polovodičových súčastok pomocou metódy SIMS s dôrazom na testovanie rôznych parametrov merania a rôznych spôsobov prípravy vzoriek. V rámci tejto práce bol navrhnutý a otestovaný držiak vzorky kompatibilný s používaným zariadením ToF-SIMS od spoločnosti IONTOF, ktorý je schopný nakláňať vzorky o definovaný uhol voči vodorovnej rovine. Tento držiak umožňuje opracovávanie vzoriek v hlavnej komore zariadenia ToF-SIMS bez nutnosti presunu vzorky medzi zariadeniami a držiakmi. Tento držiak bol použitý opracovaniu hrany vzorky TIGBT tranzistora a zobrazeniu hrany krátera predchádzajúceho merania. Na TIGBT tranzistoroch boli zobrazované vnútorné štruktúry preparované rôznymi spôsobmi. Ďalej boli optimalizované parametre merania tenckých vrstiev na molybdén-kremíkovom multivrstvovom R\"{o}ntgenovom zrkadle a na indiových multivrstvách v GaN, kde bol pozorovaný vplyv teploty vzorky behom merania SIMS na výsledné hĺbkové proifly.This thesis studies possible methods of semiconductor sample measurement by SIMS, with emphasis on testing different measurement parameters and sample preparation. Part of this master thesis deals with the design of a modified sample holder compatible with the used ToF-SIMS instrument, IONTOF company, which is capable of tilting the sample by defined angle. This holder enables sample preparation in the main chamber of the instrument without the need of transferring the sample between instruments, which limits the probability of sample contamination. This sample holder was tested by ion machining of TIGBT sample edge and by imaging of a crater edge, created in previous measurement. Edge termination structures prepared by different techniques were measured on the TIGBT samples. Further measurements with the goal of optimizing the depth resolution for thin layers were done on Molybdenum-Silicon-multilayer X-Ray Mirror. Part of the measurements was focused on comparing depth profiles measured at low temperatures. For these measurements the samples with Indium multilayers in GaN substrate were used.
Les Sims freeplay, la construction d’une ville prospère : Le reflet complexe de la société occidentale dans l'univers virtuel
Le jeu Les Sims FreePlay, héritier d'une franchise de jeux vidéo issue de l’imagination de Will Wright et développée par Maxis, s'est inscrit comme une simulation de vie captivante depuis sa première apparition en 2000. Adaptée aux plateformes mobiles par EA Games et Firemint, cette expérience ludique offre aux joueurs une immersion dans la construction et la gestion de vies virtuelles au sein d'une société simulée « simville ». Au-delà du divertissement, Les Sims FreePlay soulève des que..
Stakeholder research CoVE Water SA: CoVE Water SA the umbrella for all stakeholders
The water and sanitation sector faces well-documented issues that are challenging to address, leading to the establishment of the Platform of Vocational Excellence (PoVE) Water. This platform brings together five regional Centers of Vocational Excellence (CoVE) Water in Europe and South Africa to ensure high-quality skills and competencies in the water sector. These CoVEs facilitate collaboration among stakeholders, enabling the development of vocational education and training programs to increase awareness, responsiveness to industry needs, and address sector challenges. A few months ago, CoVE Water SA was established in South Africa to achieve the previously mentioned goals. Therefore, it is important that the following research question is answered in this initial set-up phase: What actions need to be taken to enhance the effectiveness of the CoVE Water SA? To answer this research question, several important stakeholders were interviewed. Subsequently, the interviews were analysed thematically in order to extract the most important themes and quotes, PI grids were created to assess power and interest dynamics among stakeholders, and a Social Network Analysis was conducted to understand the CoVE Water SA network and potential clusters.The research findings have unveiled key aspects for enhancing the effectiveness of CoVE Water SA. The current network in the water sector has a low density, implying that many collaborations are lacking. This leads to a high degree of interdependence within the network, resulting in a non dynamic system. The lack of collaborations, such as connections with TVET colleges, schools, farmers and local communities, results in a lack of knowledge, funding and connection to the labour market. Governmental stakeholders, like DWS, EWSeta, and BGCMA, have been identified as influential players with extensive networks and important resources, Local Authorities and Research Organizations also play important roles. Universities exhibit substantial international links, making them crucial contributors. These stakeholders have the potential to provide knowledge, collaboration, and power. These are valuable insights for CoVE Water SA, fostering network growth and effectiveness in the water sector. Furthermore, six key themes have been derived from the conducted interviews, addressing the needs of stakeholders and where CoVE can make a valuable contribution. These themes include raising awareness, reducing the skills gap in the water sector, fostering international collaborations, mitigating the labour shortage in the water sector, improving education material and establishing desired collaborations. For each theme, the interviewed stakeholders have presented their views and numerous suggestions on how CoVE Water SA can assist in addressing these issues. Additionally, stakeholders have also mentioned possible failures of CoVE Water SA, which can aid in preventing any shortcomings of the platform. Furthermore, stakeholders mentioned ongoing initiatives related to the six themes, through which they can contribute to the platform. From the Thematic Analysis, PI Grids and the SNA, a set of actions have emerged that are essential for enhancing the effectiveness of CoVE Water SA. These actions revolve around expanding and enhancing the network, organising activities and contributing to educational improvement. In terms of broadening and strengthening the network, the platform should focus on enhancing the collaborations among educational groups, building stronger relations with international institutions in Europe and Africa, involving TVETs and schools within the water network, improving stakeholder involvement and encouraging the involvement of Local Communities to increase awareness and knowledge about water issues. Furthermore, CoVE Water SA should play a role in organising activities to raise awareness of Water Resource Management. Additionally, it should assist in improving curricula, supporting students’ preparation for the workforce and making the education more practical instead of only theoretical. CoVE Water SA should also provide training and learning resources as well as comprehensive courses.However, this study recognizes several limitations that should be considered in future research and when implementing recommendations for CoVE Water SA. These limitations encompass factors like a limited scope due to resource and time constraints, minimal varied interviewee responses, and potential biases in responses. Addressing these limitations will be crucial in guiding future research and actions for CoVE Water SA.CEGM3000Civil Engineerin
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