The global classical solution to compressible Euler system with velocity alignment

In this paper, the compressible Euler system with velocity alignment and damping is considered, where the influence matrix of velocity alignment is not positive definite. Sound speed is used to reformulate the system into symmetric hyperbolic type. The global existence and uniqueness of smooth solution for small initial data is provided.Comment: 16 page

System Design of a Cheetah Robot Toward Ultra-high Speed

High-speed legged locomotion pushes the limits of the most challenging problems of design and development of the mechanism, also the control and the perception method. The cheetah is an existence proof of concept of what we imitate for high-speed running, and provides us lots of inspiration on design. In this paper, a new model of a cheetah-like robot is developed using anatomical analysis and design. Inspired by a biological neural mechanism, we propose a novel control method for controlling the muscles' flexion and extension, and simulations demonstrate good biological properties and leg's trajectory. Next, a cheetah robot prototype is designed and assembled with pneumatic muscles, a musculoskeletal structure, an antagonistic muscle arrangement and a J-type cushioning foot. Finally, experiments of the robot legs swing and kick ground tests demonstrate its natural manner and validate the design of the robot. In the future, we will test the bounding behaviour of a real legged system

Data Representativeness in Accessibility Datasets: A Meta-Analysis

As data-driven systems are increasingly deployed at scale, ethical concerns have arisen around unfair and discriminatory outcomes for historically marginalized groups that are underrepresented in training data. In response, work around AI fairness and inclusion has called for datasets that are representative of various demographic groups. In this paper, we contribute an analysis of the representativeness of age, gender, and race & ethnicity in accessibility datasets - datasets sourced from people with disabilities and older adults - that can potentially play an important role in mitigating bias for inclusive AI-infused applications. We examine the current state of representation within datasets sourced by people with disabilities by reviewing publicly-available information of 190 datasets, we call these accessibility datasets. We find that accessibility datasets represent diverse ages, but have gender and race representation gaps. Additionally, we investigate how the sensitive and complex nature of demographic variables makes classification difficult and inconsistent (e.g., gender, race & ethnicity), with the source of labeling often unknown. By reflecting on the current challenges and opportunities for representation of disabled data contributors, we hope our effort expands the space of possibility for greater inclusion of marginalized communities in AI-infused systems.Comment: Preprint, The 24th International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS 2022), 15 page

Theory Research of Value Investing Based on Market Position

This paper divides the net assets of a company into net operating assets (Equity) and net financial assets on the basis of Ohlson residual income model. Under the assumption that excess surplus income can only be generated from the net operating assets, the account of unearned revenue is selected as an efficient indicator reflecting a company’s market position and a new model of value investing theory is built based on market position. Moreover, statistics of Chinese capital market from 2003 to 2011 are used to conduct an empirical analysis to test the adjusted theoretical model. The results show that unearned revenue would significantly affect corporations’ equity value as an indicator reflecting its market position. However, an extreme value appears in its influence curve which performs as an inverted U shape. Overall, adjusted model of value investing theory built in this paper has important theoretical and practical significance in improving the development of China's capital market

bioPrint: A Liquid Deposition Printing System for Natural Actuators

This article presents a digital fabrication platform for depositing solution-based natural stimuli-responsive material on a thin flat substrate to create hygromorphic biohybrid films. Bacillus subtilis bacterial spores are deposited in the printing process. The hardware system consists of a progressive cavity pump fluidic dispenser, a numerical control gantry, a cooling fan, a heating bed, an agitation module, and a camera module. The software pipeline includes the design of print patterns, simulation of resulting material transformations, and communication with computer hardware. The hardware and software systems are highly modularized and can therefore be easily reconfigured by the user

bioPrint: an automatic deposition system for bacteria spore actuators

We propose an automatic deposition method of bacteria spores, which deform thin soft materials under environmental humidity change. We describe the process of two-dimensional printing the spore solution as well as a design application. This research intends to contribute to the understanding of the control and pre-programming the transformation of future interfaces