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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.
131

Racial/Ethnic Variation in Parenting Styles: The Experience of Multiracial Adolescents

House, Amanda N. 08 November 2011 (has links)
No description available.
132

A Longitudinal Examination of Maternal and Neighborhood Influences on Adolescent Risky Sexual Behaviors and STI Diagnosis

Khurana, Atika January 2009 (has links)
No description available.
133

Attention-Deficit/Hyperactivity Disorder and Creativity: The Role of Inhibitory Control

Lee, Alexis Whitney 25 January 2022 (has links)
No description available.
134

Co-creative Game Design as Participatory Alternative Media

Prax, Patrick January 2016 (has links)
The possibility of co-creation exists for all media, but game design has developed a culture that is unusually open to co-creation. This dissertation investigates significant cases of co-creation in mainstream games in order to explore how games can be co-created as alternative or critical media by their players. The core argument in the dissertation is that players co-create the design of a game only if certain conditions are met, namely: (1) player creation of a text or communication infrastructure that modifies the properties of the game and from which play emerges; (2) that this is done for a considerable group of players who share a particular practice of play; (3) that this is done not only by playing the game but by changing how others play it in a distinct creative activity, and (4), with the potential to subvert or contest the original design of the game. This situation where player creators have influence over the design of the game (but little power to enforce their interests) is problematic from the perspective of alternative or critical media, as alternative, local, production is seen as one reason for why a medium can have an alternative message. The industrial production of games as cultural commodities does limit the potential of co-creative game design for subversion because it reduces the level of participation in the creation process, thus keeping player creators relatively disempowered. Player creators do have influence on the design of the game, while at the same time having very little power to enforce their interests and design visions. The influence of player creators comes from the consumer power of millions of players who use co-created assets and who want to them to continue exiting, and this creates a mutually dependent relationship (and even partnership), between co-creators and commercial owners. The dissertation concludes that co-creative game design, despite limitations related to the industrial production of games as cultural commodities, is already happening, and shows a potential for turning games into alternative media.
135

Differences in IQ Scores, Referral Source and Presenting Problem Between Boys and Girls Diagnosed ADD-H

Harbeitner, Mary Hilado 08 1900 (has links)
The purpose of this research was to investigate the possibility that there are sex differences between ADD-H boys and girls. ADD-H boys and girls were compared on the four variables of presenting problem, referral source, intelligence test performance on the Wechsler Intelligence Scale for Children-Revised (WISC-R) and WISC-R subtest configuration. General demographics of the ADD-H boys and girls families were also examined. The subjects participating in this study were 39 girls and 41 boys from a large child outpatient facility in the Dallas/Fort Worth metroplex diagnosed as ADD-H between February 1984 and February 1986. No differences were found when comparing ADD-H boys and girls on all four variables. These results may suggest that there are no real differences in regards to presenting problem, referral source, IQ scores and subtest configuration between boys and girls diagnosed ADD-H.
136

Contribution à l'étude et à la mise en oeuvre de fonction de filtrage pour les brasseurs optiques dédiés au traitement multi-longueurs d'onde / Contribution to the study of filters for the implementation of optical cross-connect devices dedicated to WDM applications

Bendimerad, Djalal Falih 03 May 2012 (has links)
La demande croissante des réseaux optiques actuels en termes de bande passante résulte en un besoin d’exploiter la capacité offerte par la fibre optique. Un des moyens indispensable pour permettre ceci est l’utilisation du multiplexage en longueur d’onde. Il en résulte la nécessité d’utilisation de dispositifs, parmi lesquels le filtre optique, agiles en longueur d’onde et transparents par rapport aux débits. C’est dans ce contexte que notre travail se situe. La technologie utilisée est celle des filtres interférentiels en polarisation. Contraint par un cahier des charges particulier aux applications télécoms, le principal objectif consiste en l’augmentation des performances de ce type de filtre d’une part, et l’association de fonctionnalités additionnelles nécessaires dans les réseaux d’autre part. En utilisant le principe physique des interférences en polarisation, une structure est alors implémentée, suivant les contraintes liées aux trois paramètres majeurs du filtre que sont le contraste, la fonction d’égalisation et la reconfiguration de la bande passante. Par ailleurs, les architectures des filtres optiques diffèrent selon l’emplacement dans le réseau. Ainsi, si une architecture des plus simples est utilisée à la réception, au niveau des nœuds du réseau, celle-ci devient beaucoup plus complexe, s’adaptant à différents degrés de nœuds, et portent le nom de multiplexeurs optiques à insertion/extraction de longueur d’onde (ROADM). Un dispositif de ce type, basé sur les filtres biréfringents, est donc présenté. Une approche système est ensuite menée dans le but de mettre en évidence les avantages et les limitations de la technologie utilisée / The growing needs, in term of bandwidth in optical networks, increase over years. To satisfy these needs, the entire bandwidth of the optical fiber has to be exploited. In this context, the wavelength division multiplexing technique is used to allow the utilization of several wavelengths and results in considerably enhanced network bit-rate. However, such networks must use specific components which have particular wavelength-capabilities. Among these components, one of the most important and critical device is the optical filter. Our work is focused on the implementation of specific optical filters, using the polarization interference filter technology. The main purpose of this work is to enhance the filter rejection ratio, and to add new functionalities such as the amplitude equalization and the bandwidth tuning functions. After satisfying optical network expectations, another point, related to the filter utilization in the network, concern the device architecture which is determined by its network-location. A simple architecture with an input and an output is needed at the reception; meanwhile, a specific one is expected at network nodes. Thus, a new kind of devices is introduced, called reconfigurable optical add/drop multiplexers (ROADM). Therefore, such a device is implemented by the birefringent filter developed in this manuscript. Then, the developed device is placed in a transmission chain, and simulation results underline its limitations, by proceeding to comparison between this structure and typical optical filters. As conclusion of this work, some solutions and perspectives are presented, and very interesting challenges are highlighted
137

Programmation robotique en utilisant la méthode de maillage et la simulation thermique du procédé de la projection thermique / Robot off-line programming with a mesh-based method and thermal simulation of the thermal spray process

Cai, Zhenhua 27 February 2014 (has links)
L’objectif de cette étude est d’améliorer l’extension du logiciel de programmation hors-ligne RobotStudio™ existante et de développer une nouvelle stratégie pour générer la trajectoire du robot par rapport aux paramètres essentiels de projection thermique. Notamment, l’historique de la température par rapport à la trajectoire générée est prise en compte dans cette étude.L’extension logicielle Thermal Spray Toolkit (TST) intégrée dans le cadre de RobotStudio™ est spécialement développée pour générer la trajectoire du robot en projection thermique. L’amélioration de l’extension TST dans la nouvelle version de RobotStudio™ est mise au point sur deux modules principaux :PathKit : génération de la trajectoire sur des pièces complexes.ProfileKit : modélisation du cordon singulier du dépôt et prédiction de son épaisseur en fonction des paramètres opératoires.Les déficiences existantes de l’extension TST impliquent de mettre en œuvre une méthode plus avancée qui permettra de générer la trajectoire du robot en utilisant le maillage pour le calcul d’élément finis. Ainsi, l’opération de projection thermique pourra être menée. Dans cette étude, la méthodologie de maillage est introduite afin de fournir une stratégie de choix de points de trajectoire et l’obtention d’orientations de ces points de trajectoire sur la surface à revêtir. Un module dit MeshKit est donc ajouté dans l’extension TST afin de lui apporter ces fonctionnalités nécessaires.Un couplage entre la trajectoire du robot et la répartition de chaleur du substrat a été développé, ce qui permet d’étudier l’évolution de température pendent le processus de projection thermique. / The objective of this study is to improve the add-in package of off-line programming software RobotStudio™ and to develop a new strategy for generating the robot trajectory according to the kinematic parameters of thermal spraying. The computed temperature evolution relative to the generated robot trajectory on the coating surface is also considered in this study.The add-in package Thermal Spray Toolkit (TST) integrated in RobotStudio™ is developed to generate the robot trajectory for thermal spraying. The improved TST for new version of RobotStudio™ is composed of two principle modules:PathKit: generation of robot trajectory on the free-form coating surface.ProfileKit: modeling the coating profile and prediction the coating thickness based on kinematic parameters.The existing deficiency of TST leads to the development of an advanced robot trajectory generation methodology. In this study, the new approach implements the robotic trajectory planning in an interactive manner between RobotStudio™ and the finite element analysis software (FES). It allows rearranging the imported node created on the surface of workpiece by FES and in turns generating the thermal spraying needed robot trajectories.A coupling between the robot trajectory and the heat distribution on the substrate has been developed, which allows analyzing the temperature evolution during the thermal spray process, it helps to minimize thermal variations on the substrate and to select the appropriate execution sequence of trajectory.
138

當前土地增值稅改進可行性分析 / Current Land Values Taxation Improve Analysis

陳淑汾, Chen, Shu Fen Unknown Date (has links)
土地增值稅主要將自然增值收歸公有,以達地利共享的政策目標。自民國62年改採公告現值制度以來,由於制度及人為因素,使公告現值偏離市價,造成漲價歸私,同時促使土地投機,地價暴漲暴跌,財富分配不均,間接影響整個經濟社會的發展。本文的研究目的,旨在檢討我國土地增值稅稅制的缺點。提出改進方案。   本文的研究方法,蒐集自53年實施稅制以來的改革資料,配合稽徵機關的統計資料,作為分析與檢討的依據。並列舉英國、西德、義大利、紐澳及日本等六個國家的稅制,作一比較與評估,以供參考。   本文研究範圍,主要以增值稅的稅基為主。包括移轉時之現值,前次移轉現值或原規定地價、其他費用等。其中又以移轉時之現值在漲價總數額中居關鍵地位,因評價標準不同,所得的增值額差距亦大。公告現值雖然簡便,但卻偏離市價;實價課徵雖可正確衡量出稅基,若無整體規劃、估價、金融、仲介制度的配合,亦成空談。   本文除介紹土地課稅理論外,並由平均地權與漲價歸公的角度,確立土地增值稅的政策目標,據此探討我國稅制的缺失,歸納如下:   1.平均地權漲價歸公係一套完整的制度,但要付諸實施卻有很大的阻力。我國土地增值稅理念上依循平均地權的辦法,實施上又以課稅為主要方法,不但無法漲價歸公,反而弊病叢生。   2.民國43年按實價課徵的增值稅,由於客觀環境尚未成熟,法令規定不一及未建立土地估價制度,導致地價混亂,無依循標準而告失敗。   3.起而代之的公告現值,不但無法接近市價,反而促使土地投機、房地產價格波動起伏更大,資源扭曲,財富分配不均。如本文所分析的資料顯示,一般買賣案件中,平均有效稅率為46%,若加入「零稅基」的案件,其有效稅率為31.2%,亦即漲價歸私比率68.8%,此仍不包括自用住宅優惠稅率案件在內。實施結果與政策目標背道而馳。   實價課徵的採行雖較能達到「漲價歸公」,但在技術上面臨最大的困難就是如何掌握實際的買賣價格。自英、西德、義大利、紐澳及日本等國稅制的比較與評估中,可知技術上的困難可以克服。特別在鼓勵投資,抑制投機方面,英國准許扣除較高的投資成本及投資利潤;義大利對於土地建築期間的增值,不列入課稅範圍;日本更依其持有期間,劃分長期、短期、超短期,課以不同稅率。各有所長,值得借鏡。   最後,針對目前增值稅稅制,提出如下建議:   1.全面改制按實價課徵,訂定賞施的時間表及步驟。為改制前的各項配合措施,作有計劃的準備。   2.修法規定,土地買賣須經中介機構,非經此一機構不能買賣。   3.建立健全的估價制度,重視專業人員的培訓。   4.改制的過渡時期,如前次成本認定問題,費用扣除比率,房地併售價格劃分,均應審慎處理。   5.為防止土地投機,依據持有土地時間長短,課以不同稅率,或開徵「變更使用捐」以因應。加強人民誠實報稅的觀念,發揮自動勾稽的效果。
139

Technology for photonic components in silica/silicon material structure

Wosinski, Lech January 2003 (has links)
The main objectives of this thesis were to develop a lowtemperature PECVD process suitable for optoelectronicintegration, and to optimize silica glass composition forUV-induced modifications of a refractive index in PECVDfabricated planar devices. The most important achievement isthe successful development of a low temperature silicadeposition, which for the first time makes it is possible tofabricate good quality low loss integrated components whilekeeping the temperature below 250oC during the entirefabrication process. Two strong absorption peaks thatappear at1.5 mm communication window due to N-H and Si-H bonds have beencompletely eliminated by process optimization. This openspossibilities for monolithic integration with other,temperature sensitive devices, such as semiconductor lasers anddetectors, or polymer-based structures on the common siliconplatform. PECVD technology for low loss amorphous silicon inapplication to SiO2/Si based photonic crystal structures hasbeen also optimized to remove hydrogen incorporated during thedeposition process, responsible for the porosity of thedeposited material and creation of similar to silica absorptionbands. Change of the refractive index of germanium doped silicaunder UV irradiation is commonly used for fabrication of UVinduced fiber Bragg gratings. Here we describe our achievementsin fabrication of fiber Bragg gratings and their application todistributed sensor systems. Recently we have built up a laserlab for UV treatment in application to planar technology. Wehave demonstrated the high photosensitivity of PECVD depositedGe-doped glasses (not thermally annealed) even without hydrogenloading, leading to a record transmission suppression of 47dBin a Bragg grating photoinduced in a straight buried channelwaveguide. We have also used a UV induced refractive indexchange to introduce other device modifications or functions,such as phase shift, wavelength trimming and control ofpolarization birefringence.The developed low temperature technology and the UVprocessing form a unique technology platform for development ofnovel integrated functional devices for optical communicationsystems. A substantial part of the thesis has been devoted tostudying different plasma deposition parameters and theirinfluence on the optical characteristics of fabricatedwaveguides to find the processing window giving the besttrade-off between the deposition rate,chamber temperatureduring the process, optical losses and presence of absorptionbands within the interesting wavelength range. The optimalconditions identified in this study are low pressure (300-400mTorr), high dilution of silane in nitrous oxide and high totalflow (2000 sccm), low frequency (380 KHz) RF source and high RFpower levels (800-1000 W). The thesis provides better understanding of the plasmareactions during the deposition process. RF Power is the keyparameter for increasing the rate of surface processes so as toaccommodate each atomic layer in the lowest energy statepossible. All the process conditions which favor a moreenergetic ion bombardment (i.e. low pressure, low frequency andhigh power) improve the quality of the material, making it moredense and similar to thermal oxide, but after a certain pointthe positive trend with increasing power saturates. As theenergy of the incoming ion increases, a competing effect setsin at the surface: ion induced damage and resputtering. Finally, the developed technologies were applied for thefabrication of some test and new concept devices for opticalcommunication systems including multimode interference (MMI)-based couplers/splitters, state-of-the-art arrayed waveguidegrating-based multi/ demultiplexers, the first Bragg gratingassisted MMI-based add-drop multiplexer, as well as moreresearch oriented devices such as a Mach-Zehnder switch basedon silica poling and a Photonic Crystal-based coupler. <b>Keywords:</b>silica-on-silicon technology, PECVD, plasmadeposition, photonic integrated circuits, planar waveguidedevices, UV Bragg gratings, photosensitivity, arrayed waveguidegratings, multimode interference couplers, add-dropmultiplexers.
140

Demonstration of a Novel Reconfigurable Optical Add-Drop Multiplexer

Yang, Cheng-Hao 18 July 2011 (has links)
In response to the development of a next-generation networking (NGN) generalized multi-protocol label switching (GMPLS) technology is required for automatically switched optical network (ASON). Reconfigurable optical add-drop multiplexer (ROADM) is an indispensable device for the ASON, and the dense wavelength division multiplexed (DWDM) signals can be transmitted through the network under the management of the network administrator to configure dynamic customer needs and the desired quality of service (QoS). The ROADM can also increase the efficiency of utilizing the existing capacity of the optical fiber lines and can reduce or waive to set up additional optical fiber lines. This thesis studies a novel ROADM based on the arrayed waveguide grating (AWG) and the fiber Bragg grating (FBG) to overcome that the current ROADM cannot process that the input signal channels is greater than the wavelengths channels of AWG. Many types of ROADMs have been proposed and realized through different optical devices. Among these, hybrid optical circulator and FBG based ROADM is more attractive because of its low crosstalk and polarization insensitivity. However, it still suffers from many component counts and high insertion losses due to the use of many circulators and a multiplexer-demultiplexer pair. In this master thesis, we focus on demonstrating a novel ROADM and evaluating its crosstalk performance. It is found that the proposed ROADM has the advantage on extending the number of wavelength signal to make the system configurable and flexible.

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