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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

如何叛逃張愛玲--朱天文與胡蘭成的文學關係 / Separate the world of Chang, Eileen -- literature relations between Zhu,Tien-wen and Hu,Lan-cheng.

羅郁玫, Lo, Yu Mei Unknown Date (has links)
朱天文由於家學淵源,很早即接觸了父親口中所說的好的作品-張愛玲的文本,而張愛玲的才氣與華麗的文字很讓朱天文著迷,而朱天文早期的作品的確是深受張愛玲的影響,然而,學者將張愛玲的文學地位抬至極高,且整理出受到張愛玲所影響的作家名單,當然,朱天文亦名列其中。本章主要是整理出所謂「張派」的研究名單,究竟是何種文風特色的作家作品被列名,主要的論者有哪些?他們又是持何種觀點呢?而回到朱天文早期的創作文本,張愛玲是否真的對朱天文造成莫大的影響?面對張愛玲,朱天文又有何種看法以及觀感,這對於其文學實踐又產生了什麼作用呢? 真要談朱天文,就得從三三時期開始說起,從創辦、集刊名稱、體例,以及週遭活動開始觀察,胡蘭成的文章思想以及啟蒙又對其產生如何的影響。 在黃錦樹評論朱天文的文章當中,點出《荒人手記》是對胡蘭成的致意,並引用胡蘭成〈來寫朱天文〉文中的比喻,將朱天文與日本祭祀的巫女相比併,究竟朱天文在文學創作上呈現何種特色呢?本文將回歸朱天文的創作文本,並藉由審視黃錦樹與王德威的說法,並且參考張瑞芬的研究,探討朱究竟是向張愛玲致意或是向胡蘭成靠攏?並且透過「巫」的意象觀察朱天文的書寫以何姿態展現,以及為什麼要以「巫」的姿態書寫。 本文從朱天文的三三時期開始耙梳,觀察朱天文的文章從早期張愛玲的影響與胡蘭成的文學淵源,乃至最後成功叛逃張派作品,自成天文風格的文學創作,看這位臺灣當代重要的小說家是如何以文字煉金術士的功夫奢靡地實踐文學這華麗的修行。
192

Contributions à la simulation et à l'analyse de discrétisation de processus, et applications.

GOBET, Emmanuel 24 November 2003 (has links) (PDF)
Nous présentons quelques contributions à la simulation et à l'analyse de discrétisation de processus, avec leurs applications notamment en finance. Nous avons regroupé nos travaux selon 4 thèmes: 1. statistique des processus avec observations discrètes; 2. couverture en temps discret en finance; 3. sensibilités d'espérances; 4. analyses d'erreurs de discrétisation. Le premier chapitre sur la statistique des processus est assez indépendant du reste. En revanche, les trois autres chapitres correspondent à une cohérence et une progression dans les questions soulevées. Néanmoins au fil de la lecture, on remarquera des liens entre les quatre parties: différentiation par rapport à des domaines et amélioration de simulation de temps de sortie, sensibilités d'espérances et statistique asymptotique avec le calcul de Malliavin, sensibilités d'espérances et analyse d'erreur etc... Les preuves des résultats s'appuient notamment sur les outils du calcul de Malliavin, des martingales, des Équations aux Dérivées Partielles et de leurs liens avec les Équations Différentielles Stochastiques.
193

Improving user comprehension and entertainment in wireless streaming media : introducing cognitive quality of service

Wikstrand, Greger January 2003 (has links)
<p>In future mobile networks service quality might be poor. A new measure is needed to be able to assess services in terms of their effectiveness and usefulness despite their lacking visual appeal. Cognitive Quality of Service is a way to measure the effectiveness in use of a networked service.</p><p>This thesis introduces Cognitive Quality of Service and puts it in relation to other ways to measure quality in streaming media. Through four studies the concept is used to improve multicast performance in a WLAN, to assess the effectiveness of simple animations compared to video, to build an application that fuses video and animations and to assess the differences between various levels of streaming video quality.</p><p>Guidelines on how to measure Cognitive Quality of Service are introduced based on a review of available literature and later analyzed in light of the studies presented in the thesis. It turns out that the guidelines are sound and should be used as a basis for assessing Cognitive Quality of Service.</p><p>Finally, the usefullness of Cognitive Quality of Service is analyzed. It turns out that it is especially useful when comparing different media, e.g. animations and video. In the video only case even bit-rate might be a useful predictor of subjective quality.</p> / <p>I framtiden kommer användare att titta på videosekvenser i trådlösa apparater, exempelvis mobiltelefoner. På grund av tekniska faktorer som störningar och på grund av kostnaden för det kommer den kvalitet som de erhåller inte att vara jämförbar med till exempel den kvalitet som kan erhållas när man tittar på tv. Trots det kan man anta att sådan video kan vara intressant och upplysande.</p><p>I avhandlingen introduceras och används begreppet Cognitive Quality of Service (CQoS) - kognitiv servicekvalitet. Begreppet definieras av att den överföring som ger den bästa förståelsen och känslomässiga reaktionen också har bäst CQoS. För att mäta CQoS bör man följa vissa riktlinjer, särskilt som det är svårt att mäta förståelse i samband med att man tittar på video.</p><p>Författaren har tillsammans med medarbetare tittat på hur man kan förbättra förhållandena för själva radioöverföringen (studie I). Genom en algoritm som ger multicast-paket bättre skydd mot kollisioner visas att man kan erhålla förbättrad överföringskapacitet för strömmande video i ett trådlöst nätverk.</p><p>Animeringar är ett alternativ till video som kräver låg bandbredd. I ett experiment har man undersökt hur väl animeringar står sig mot video av olika kvalitet när det gäller att upplysa användaren och ge en bra upplevelse (studie II). Det visade sig att animeringar var bättre för förståelsen medan video gav en bättre känslomässig upplevelse. Vanare åskådare föredrog videon medan ovanare åskådare föredrog animeringarna.</p><p>Frågan som ställdes var då hur man kunde kombinera respektive mediums fördelar för att få en så bra blandning som möjligt. Å ena sidan var animeringarna billiga och lätta att förstå medan videon var dyrare och mer intressant. Ett prototypgränssnitt skapades. Där kunde användaren själv välja vilken mix mellan de två alternativen som skulle visas (studie III). Det visade sig att försökspanelen föredrog video och dessutom ville ha mer information om spelare och match.</p><p>Trots animationernas förträfflighet kan man anta att det ändå är video som kommer att dominera i framtiden. En sista studie genomfördes för att se om man kunde finna liknande resultat vid olika kvalitetsgrader i video som man tidigare hade funnit mellan video och animeringar (studie IV). Det visade sig att så länge man höll sig till ett format var sambanden enklare. Mer var helt enkelt bättre upp till en viss gräns där det inte tillförde mer att öka överföringsresurserna för videon.</p><p>Sammanfattningsvis visar studierna att CQoS kan ge värdefull designkunskap. I synnerhet när man jämför olika presentationsformer som i det här fallet animeringar och video. Nästa steg blir att gå vidare med att applicera CQoS i tvåvägskommunikation, särskilt i Conversational Multimedia (CMM)– ungefär bildtelefoni – där det är särskilt goda möjligheter att sammanställa en för omständigheterna anpassad mediamix.</p>
194

Business and the grid : economic and transparent utilization of virtual resources /

Weishäupl, Thomas. January 2006 (has links)
Univ., Diss.--Wien, 2006.
195

Prieigos prie bevielio tinklo resursų valdymas panaudojant vietos informaciją / Wireless LAN location-based access control

Petrauskienė, Rasa 01 September 2011 (has links)
Tobulėjant mobilioms technologijoms vietos informacija tapo svarbi prieigos valdymui. Šiame darbe analizuojamos vietos informacijos derinimo su autentifikacijos ir prieigos valdymo mechanizmais galimybės. Darbe išskirti vietos informacijos įvedimo į autentifikacijos, prieigos valdymo ir atskaitomybės procesus privalumai. Pristatomas vietos informacija paremtas prieigos prie tinklo resursų valdymo modelis, kuris leidžia padidinti teisingo autentifikavimo tikimybę bei išplėsti prieigos valdymo galimybes. Suprojektuota prieigos prie bevielio tinklo valdymo sistema, pritaikyta veikti kelių aukštų pastate. Modelis yra suderinamas su OGC (Open GeoSpatial Consortium) ir Geo-RBAC (RBAC modelio išplėtimu), į jį įtraukti kitų tipų vietos informacija pagrįsti požymiai. Darbe pristatomi prieigos valdymo išplėtimai: periodiškumo algoritmas ir erdvinių požymių įvertinimo algoritmas, naudojantis susiejimo funkcijas ir įvertinantis vietos nustatymo patikimumą. Pasiūlyto prieigos valdymo modelio veikimas įvertinamas eksperimentais, nurodomi jo galimi pažeidžiamumai. / Location-based Access Control LBAC techniques allow taking users’ physical location into account when determining their access privileges. The analysis of possibilities of integrating location information into access control and authentication is provided. I show the advantages of using location information for authentication and access control. I present location-based access control model that can increase the probability of correct authentication. I design wireless LAN location-based access control system that is used in building of several floors. The model is compliant with OGC (Open GeoSpatial Consortium) and Geo-RBAC (the extent of RBAC model); it integrates other types of location-based features. I describe the periodicity algorithm of location-based access control and design the policy enforcement algorithm that uses location mapping functions and the evaluation of confidence. The model is evaluated by testing the speed of the system and computer resources used by the system. The vulnerabilities of location-based access control are discussed in the context of sniffing, highjacking, DoS and warmhole attacks.
196

An indoor-location sensing system using WLAN and ultrasonic/radio technologies

Hyun, Eugene Jaiho 20 August 2008 (has links)
Ubiquitous location-aware systems and services are becoming a reality as made evident by the widely known Global Position System (GPS). However, indoor location-aware sensing systems are not yet commercially viable since: (i) for a GPS-based system, the signals attenuate and can multipath indoors causing weak signal and poor location (ii) for a Radiolocation-based system, the propagation of radio signals are complex and difficult to model. In this paper, we present RadLoco, a location-sensing system that uses IEEE 802.11 Wireless LAN survey techniques to create a radio Received Signal Strength (RSS) map of the propagation environment. To provide accurate location estimation, we make use of a kernel-window estimation algorithm that is used to approximate the probability density function of RSS measurement and location. Unlike parametric estimators, this non-parametric kernel approach requires less knowledge of the distributions of location and measurements, and also makes use of the prior knowledge of mobile terminal location to reduce the estimation error. The novelty of the system is an innovative radio/ultrasonic sensory network which allows for rapid data collection whereas the standard technique of defining a grid of survey points with measuring rulers, chalk, and tape would require a great amount of manpower. Using this sensory network, a 2000m sq. office building is surveyed in four hours by a single technician. Our experimental results indicate the mobile terminal is located on the correct oor with over 98% accuracy and with a mean error of less than 2.5m from the true location.
197

Received signal strength calibration for wireless local area network localization

Felix, Diego 11 August 2010 (has links)
Terminal localization for indoor Wireless Local Area Networks (WLAN) is critical for the deployment of location-aware computing inside of buildings. The purpose of this research work is not to develop a novel WLAN terminal location estimation technique or algorithm, but rather to tackle challenges in survey data collection and in calibration of multiple mobile terminal Received Signal Strength (RSS) data. Three major challenges are addressed in this thesis: first, to decrease the influence of outliers introduced in the distance measurements by Non-Line-of-Sight (NLoS) propagation when a ultrasonic sensor network is used for data collection; second, to obtain high localization accuracy in the presence of fluctuations of the RSS measurements caused by multipath fading; and third, to determine an automated calibration method to reduce large variations in RSS levels when different mobile devices need to be located. In this thesis, a robust window function is developed to mitigate the influence of outliers in survey terminal localization. Furthermore, spatial filtering of the RSS signals to reduce the effect of the distance-varying portion of noise is proposed. Two different survey point geometries are tested with the noise reduction technique: survey points arranged in sets of tight clusters and survey points uniformly distributed over the network area. Finally, an affine transformation is introduced as RSS calibration method between mobile devices to decrease the effect of RSS level variation and an automated calibration procedure based on the Expectation-Maximization (EM) algorithm is developed. The results show that the mean distance error in the survey terminal localization is well within an acceptable range for data collection. In addition, when the spatial averaging noise reduction filter is used the location accuracy improves by 16% and by 18% when the filter is applied to a clustered survey set as opposed to a straight-line survey set. Lastly, the location accuracy is within 2m when an affine function is used for RSS calibration and the automated calibration algorithm converged to the optimal transformation parameters after it was iterated for 11 locations.
198

Untersuchung von Methoden zur Laufzeitmessung in Wireless LAN Netzwerken zum Zwecke der Positionsbestimmung

Haustein, Mario 17 May 2011 (has links) (PDF)
Ortsbasierte Dienste erfreuen sich in den letzten Jahren starker Beliebtheit. Für deren Umsetzung sind sog. Lokalisierungsdienste notwendig, welche eine Ortung von Mobilgeräten erlauben. Das GPS stellt den wohl populärsten Lokalisierungsdienst dar, ist jedoch innerhalb von Gebäuden nur sehr beschränkt einsetzbar. In der Vergangenheit wurden deshalb Methoden vorgeschlagen, die zur Positionsbestimmung auf die Messung der Empfangsfeldstärke von WLAN-Aussendungen zurückgreifen. Im Rahmen der Diplomarbeit soll untersucht werden, ob sich ebenfalls eine Postionsbestimmung anhand von Laufzeiten der WLAN-Signale umsetzen lässt. Bedingung hierbei ist, dass der Lokalisierungsdienst - eine reine Softwarelösung darstellt und keine Modifikationen an Hard- oder Firmware voraussetzt und - die Lokalisierung ohne für diese Zwecke ausgelegte Spezialhardware umsetzbar ist. Diese Anforderungen sollen sicherstellen, dass der zu entwickelnde Lokalisierungsdienst mit bereits installierter, handelsübliche Hardware umsetzbar ist. Es sind in Frage kommende Verfahren zur Bestimmung der Signallaufzeit zu erörtern. Für die Laufzeitmessung in Frage kommenden Zeitquellen sollen zugänglich gemacht und auf ihre Tauglichkeit untersucht werden. Durch Messreihen ist zu untersuchen, ob mit den vorgeschlagenen Messverfahren eine Lokalisierung möglich ist und in welchem Rahmen sich die zu erwartende Genauigkeit bewegt. Die in dieser Arbeit beschriebenen Konzepte sollen im Rahmen einer Proof of Concept Anwendung implementiert werden. Die Software soll unter dem Gesichtspunkt der Wiederverwendbarkeit entwickelt werden, um eine spätere Nutzung im Rahmen anderer Projekte zu ermöglichen.
199

Vida na rede : uma análise antropológica da virtualidade

Dornelles, Jonatas January 2008 (has links)
Essa tese de doutorado tem o caráter antropológico e é o resultado de uma investigação sobre a virtualidade gerada pelo ciberespaço, que é materializado na Rede de computadores da Internet e as atuais tecnologias digitais e informáticas. Foram pesquisadas três instâncias empíricas em que a dimensão virtual se consolida como condição de interação social: praticantes de jogos virtuais em ambientes de Lan House; usuários da plataforma virtual do Orkut; e, o espaço virtual 3D disponibilizado pelo software Second Life. O trabalho analítico e comparativo considerou as especificidades de cada situação investigada e as recorrências passíveis de generalização. O objetivo do estudo foi responder às perguntas de como os indivíduos contemporâneos lidam com trânsito regular entre as dimensões do on-line (virtual) e do off-line (real), assim como investigar em que medida suas vidas são afetadas pela alternância constante entre esses modos espacial e temporalmente diferentes de comunicação e de interação social. Seguindo o caráter antropológico do estudo foi possível reconstruir os diversos sentidos dados pelos sujeitos ao que seria uma “vida” virtual conectada à “vida” real, que deve ser considerada a condição contemporânea de existência e de representação da realidade dos segmentos investigados. / This PhD thesis has an anthropological character and it is the result of an investigation on the virtuality generated by the cyberspace that is materialized in the Internet and the current digital technologies and computer sciences. Three empirical instances were researched which the virtual dimension consolidates as condition of social interaction: players of virtual games in Lan House atmosphere; users of the virtual platform of Orkut; and, the virtual 3D space showed by the Second Life software. The analytic and comparative work considered the specific elements of each situation investigated and the possible agreement among them. The objective of the study was to answer to the questions of how contemporary individuals work with the regular traffic among the virtual and real dimensions, and how they lives are affected by the constant alternation between those different forms of time and space communication and social interaction. Following the anthropological character of the study, was possible to reconstruct the several meanings given by the subjects to the "virtual life" connected to the "real life", that should be considered as being the contemporary condition of existence and representation of the reality by the investigated segments.
200

Redes locais e downsizing de sistemas de informação: um estudo em bancos brasileiros

Diniz, Eduardo Henrique 06 April 1994 (has links)
Made available in DSpace on 2010-04-20T20:15:02Z (GMT). No. of bitstreams: 0 Previous issue date: 1994-04-06T00:00:00Z / Ao optar por redes locais (LAN - Local Area Networks) de microcomputadores, em lugar de ampliar os investimentos nos sistemas de grande porte que já possuem instalados, diversas empresas do setor bancário no Brasil estão adotando o conceito de downsizing, expressão que identifica a política de redução do porte dos equipamentos de informática utilizados para executar o processamento de informações corporativas. A adoção deste tipo de política, longe de ser uma ocorrência episódica, tem características de tendência geral para o setor nos próximos anos. Este trabalho faz uma investigação do alcance dessa tendência no setor bancário brasileiro e uma análise dos fatores que têm impulsionado a implementação de diferentes estratégias de downsizing de sistemas de informação.

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