Overview of Ingard and Maling’s1974 Paper on Physical Principles of Noise Reduction: Energy Considerations, Noise Reducing Elements and Sound Absorbing Materials

Overview of Ingard and Maling’s1974 Paper on Physical Principles of Noise Reduction: Energy Considerations, Noise Reducing Elements and Sound Absorbing Material

Faculty and student feedback of synchronous distance education in a multi-university learning consortium

The Texas Learning Consortium (TLC) began as a partnership between the foreign language departments at 5 small, private, liberal arts universities, where each specializes in a small number of different world languages to increase the course offerings to their students without the expense of adding additional faculty on every campus. Each university offers their language courses to consortium students in a real-time, interactive, distance education format. In Fall 2017, the consortium expanded beyond foreign languages, and the first engineering course, Statics, was offered in this synchronous, distance format. As background, this paper will provide an overview of the technology used in the classrooms and some of the administrative obstacles that were overcome in scheduling, registration and information technology. The paper will also reflect on the impact of this particular technological implementation on various teaching styles in both foreign language and engineering courses, especially compared to other distance engineering education in the literature, with a purpose of analyzing the model’s suitability for expansion into other engineering courses or a fully accredited consortium based engineering program. Student and faculty satisfaction surveys will additionally provide insight as to whether this distance format is the right fit for campuses used to high-touch learning environments.Cockrell School of Engineerin

Recognizing Focal Liver Lesions in Contrast-Enhanced Ultrasound with Discriminatively Trained Spatio-Temporal Model

The aim of this study is to provide an automatic computational framework to assist clinicians in diagnosing Focal Liver Lesions (FLLs) in Contrast-Enhancement Ultrasound (CEUS). We represent FLLs in a CEUS video clip as an ensemble of Region-of-Interests (ROIs), whose locations are modeled as latent variables in a discriminative model. Different types of FLLs are characterized by both spatial and temporal enhancement patterns of the ROIs. The model is learned by iteratively inferring the optimal ROI locations and optimizing the model parameters. To efficiently search the optimal spatial and temporal locations of the ROIs, we propose a data-driven inference algorithm by combining effective spatial and temporal pruning. The experiments show that our method achieves promising results on the largest dataset in the literature (to the best of our knowledge), which we have made publicly available.Comment: 5 pages, 1 figure

Budget-Constrained Dynamics in Multiagent Systems

The paper introduces a notion of a budget-constrained multiagent transition system that associates two financial parameters with each transition: a pre-transition minimal budget requirement and a post-transition profit. The paper proposes a new modal language for reasoning about such a system. The language uses a modality labeled by agent as well as by budget and profit constraints. The main technical result is a sound and complete logical system that describes all universal properties of this modality. Among these properties is a form of Transitivity axiom that captures the interplay between the budget and profit constraints

Modularized Zero-shot VQA with Pre-trained Models

Large-scale pre-trained models (PTMs) show great zero-shot capabilities. In this paper, we study how to leverage them for zero-shot visual question answering (VQA). Our approach is motivated by a few observations. First, VQA questions often require multiple steps of reasoning, which is still a capability that most PTMs lack. Second, different steps in VQA reasoning chains require different skills such as object detection and relational reasoning, but a single PTM may not possess all these skills. Third, recent work on zero-shot VQA does not explicitly consider multi-step reasoning chains, which makes them less interpretable compared with a decomposition-based approach. We propose a modularized zero-shot network that explicitly decomposes questions into sub reasoning steps and is highly interpretable. We convert sub reasoning tasks to acceptable objectives of PTMs and assign tasks to proper PTMs without any adaptation. Our experiments on two VQA benchmarks under the zero-shot setting demonstrate the effectiveness of our method and better interpretability compared with several baselines.Comment: accepted as Findings in ACL 202

Tire Cavity Induced Structure-Borne Noise Study with Experimental Verification

Structure-borne road noise is an important factor affecting passengers’ overall riding experience. It is well-known that the fundamental acoustic resonance of the tire cavity can generate net forces on the rim, usually in the vicinity of 200 Hz. This effect can be reduced by placing sound absorbing material within the tire cavity. However, modifying the design of the tire and suspension system to decrease the cavity noise influence without the need for adding sound absorbing material would clearly be beneficial in terms of decreased cost and complexity. Previous finite element simulations have shown that tires in which even treadband circumferential flexural modes align in frequency with the vertical cavity acoustic mode exhibit relatively low cavity-related vibration levels. In contrast, when odd circumferential treadband modes align in frequency with the vertical cavity mode, cavity-related vibration levels are relatively high. This behavior follows from the fact that the contact patch imposes a zero radial velocity condition on the treadband, and when an odd mode is driven on the remainder of the treadband, one maximum in the modal distribution appears at the top of the tire, which then matches the vertical cavity mode shape and creates a net force on the rim. Here, the simulation findings were verified based on experimental measurement of hub vibration and tire dispersion relations

Finite Element Study of Acoustic Mode Force Transmission in a Loaded, Structural-Acoustical Tire Model

Concerns about tire radiation noise arise from traffic planning, environmental and pedestrian safety stand-points, while from the vehicle passengers\u27 perspective, noise transmitted to the vehicle interior is more im-portant: the latter concern is addressed in this paper. Tire vibration propagates through the vehicle suspension and causes objectionable interior noise; such noise is usually defined as structure-borne noise. Sound absorbing materials have good absorption properties at higher frequencies and are effective at eliminating airborne tire noise, which usually dominates above 500 Hz. Thus, the reduction of relatively low frequency structure-borne tire noise is a continuing focus of auto manufacturers. Among all the structure-borne tire noise sources, the tire internal cavity resonance is a very strong contributing factor, normally near 200 Hz for current tires, especially since this resonance can be easily perceived by passengers. Reduction of this mode can be achieved by insert-ing sound absorbing material within the tires. However, beyond the cost of such tires, there are durability concerns and it is difficult to repair such tires without damaging their sound absorptive properties. Thus, an improved design of the tire-rim and suspension system to decrease the structure-borne cavity noise still has many benefits. In that context, a fully-coupled structural-acoustic finite element tire model with ground contact is described here. The model was established in the Abaqus/CAE 6.13-4 environment, and was driven by forces near the contact patch. The tire surface velocities and hub center accelerations were calculated in order to study how the internal air cavity would affect the force transmissibility character of the tire structure and how the input force would influence the response of the tire system. It has been found that there can be strong coupling between circumferentially asymmetric treadband modes and the verified acoustic cavity mode which amplifies the structure-borne transmission, and which should thus be avoided