Numerical and Experimental Studies of Blocked Force Determination on an Offset Interface for Plate and Shell Structures and Duct Acoustic Systems

Blocked force determination is an alternative to the more routine method of inverse force determination using classical transfer path analysis. One advantage of determining blocked forces is that there is no need for the source to be detached or isolated from the system. Another advantage is that calculated blocked forces are appropriate when modifications are made on the receiver side of the interface. This insures that the blocked forces are suitable for utilization in analysis models where receiver system modifications are considered. Difficulties in using the approach arise when interface locations are difficult to instrument. This thesis demonstrates that blocked forces may also be determined along a continuous interface offset from bolted connections or isolators making the method more convenient to use. This offset interface strategy is demonstrated for plate and shell structures using both simulation and measurement. Recommendations are made for selecting the number of forces and blocked force locations along this offset interface. The number of blocked forces required will be prohibitive at higher frequencies since the structural wavelength is inversely proportional to the square root of frequency. An uncorrelated blocked force method is applied at high frequencies and the predicted results are validated for different structural systems. It is shown that predicted results in one-third octave bands are accurate using the uncorrelated assumption, and that uncorrelated forces can be used to predict the effect of modifications on the receiver side of the interface. Similar approaches are then used for the analogous acoustic case where acoustic blocked sources are positioned on a cross-sectional plane inside a duct. It is demonstrated that correlated and uncorrelated assumptions can be used to predict the sound pressure level downstream of the source at low and high frequencies respectively. This is the case even if the duct system downstream of the cross-sectional plane is modified. The approach seems promising for simulating acoustic sources in heating, ventilation, and air conditioning ducts above the plane wave cutoff frequency

Les cadres symbiotiques : la présentation d'ensemble de la vidéo et de son installation

Comme un chef trouverait ridicule qu'un client qui goûte son plat lui demande de décrire la saveur et pourquoi il le fait, certains artistes ne veulent pas s’asseoir et interpréter leurs œuvres à la place du spectateur. Surtout que les artistes ont d’autres raisons de rester silencieux: peut-être que les œuvres elles-mêmes sont des objets obscurs auxquels les artistes veulent échapper ou que celles-ci répondent à des questions non résolues. Les œuvres seraient des réflexions non avouées. Cependant, une relation s’établit entre les artistes et leurs pratiques. Je la découvre à travers ma démarche de création en maîtrise, accompagnée de tous les questionnements techniques et émotionnels, que je termine avec mon exposition – Rivière absente. Pour décrire mon cheminement, je commence par une interprétation du concept de symbiose. Ce concept s'applique à l'ensemble des installations de mon exposition. Deuxièmement, j'analyse l’influence de l’animation et de la vidéo sur ma production en accordant plus d'importance à l'œuvre finale et son échange avec le spectateur qu'au médium lui-même. À la fin, j’analyse l'ensemble des sentiments et des réflexions sur la notion de nostalgie qui donne naissance à mes scénarios et à ma pratique. En plaçant cette partie à la fin, je tente de mettre en avant-plan les émotions que l'œuvre transmet tout en mettant de côté l'analyse technique

Microprocessor Design with Dynamic Clock Source and Multi-Width Instructions

This paper introduces a novel 32-bit microprocessor, based on the RISC-V instruction set architecture, is designed,utilising a dynamic clock source to achieve high efficiency, overcoming the limitations of hardware delays. In addition, the microprocessor is also aimed to operate with both base (32-bit) instructions and 16-bit compressed instructions. The testing of the design is carried out using ModelSim with an ideal result

Facial Expression Retargeting from Human to Avatar Made Easy

Facial expression retargeting from humans to virtual characters is a useful technique in computer graphics and animation. Traditional methods use markers or blendshapes to construct a mapping between the human and avatar faces. However, these approaches require a tedious 3D modeling process, and the performance relies on the modelers' experience. In this paper, we propose a brand-new solution to this cross-domain expression transfer problem via nonlinear expression embedding and expression domain translation. We first build low-dimensional latent spaces for the human and avatar facial expressions with variational autoencoder. Then we construct correspondences between the two latent spaces guided by geometric and perceptual constraints. Specifically, we design geometric correspondences to reflect geometric matching and utilize a triplet data structure to express users' perceptual preference of avatar expressions. A user-friendly method is proposed to automatically generate triplets for a system allowing users to easily and efficiently annotate the correspondences. Using both geometric and perceptual correspondences, we trained a network for expression domain translation from human to avatar. Extensive experimental results and user studies demonstrate that even nonprofessional users can apply our method to generate high-quality facial expression retargeting results with less time and effort.Comment: IEEE Transactions on Visualization and Computer Graphics (TVCG), to appea

The time we experience : understanding the phenomenologies of temporal passage and presentness

This dissertation explores what is involved in the alleged phenomenologies of the passage of time and the present, two phenomenological data that are normally cited to support the A-theory of time. It argues that the phenomenology corresponding to the purported passage phenomenology is that of dynamic changes in things’ states, and the phenomenology corresponding to the purported presentness phenomenology is that of (only) some things and events occurring simpliciter. It claims that these illusory phenomenologies are products of the feature of our perceptual experience of having a confined temporal horizon, which includes three aspects – limited access, involuntariness, and directionality. It also argues that the illusory phenomenologies of dynamic change and things and events occurring simpliciter, despite being at odds with the B-ontology, do not lend support to the A-theory of time. Furthermore, it provides insight into why our perceptual experience has a confined temporal horizon and how the intuitive beliefs that we experience temporal passage and presentness arise from the illusory phenomenologies