Singularity Structures of Linear Inviscid Damping in a Channel

This paper studies singularity structures of the linear inviscid damping of two-dimensional Euler equations in a finite periodic channel. We introduce a recursive definition of singularity structures which characterize the singularities of the spectrum density function from different sources: the free part and the boundary part of the Green function. As an application, we demonstrate that the stream function exhibits smoothness away from the channel's boundary, yet it presents singularities in close proximity to the boundary. The singularities arise due to the interaction of boundary and interior singularities of the spectrum density function. We also show that the behavior of the initial data and background flow have an impact on the regularity of different components of the stream function

Human Capital and Risky Asset Allocation

Much research has been done to examine the relation between investors\u27 human capital and their financial asset allocation. While some showed that the value of human capital should be taken into consideration to make financial asset allocation decisions on the composition of investing portfolios, most argued not. In this paper, we selected the monthly return of 9 industrial ETFs from June of 2007 to July 2011, used the present value of total future income as estimate of human capital, and relied on the Mean-Variance Optimal Asset Allocation framework to reexamine if human capital will impact investors optimal financial portfolios. Based on our tests, we found significant connection between human capital and risky asset allocation, which resulted in significant change to weights allocated to the risk assets to create a Mean-Variance optimal portfolio

The influence of contact area between implant and its adjacent teeth on finite element analysis

The aim of this work is to investigate the influence of contact area between the first molar implant and its adjacent teeth on finite element analysis. Five types of finite element contact models containing implant and its adjacent teeth were established: non-contact model (C0), contact models with different contact area (C1, C2, C3, C4). An occlusal force was applied to finite element models to calculate the stress of implant and bone interface on mandible. Compared with the group C0, the stress of alveolar bone surrounding the implant in other groups decreased 88.08 % at most, but the stress of cancellous bone surrounding the natural teeth increased 59.42 %. In summary, a proper small contact area can not only reduce the stress concentration on the implant region, but also can avoid an excessive stress in the periodontal ligament and alveolar bone around the natural teeth. The finite element results revealed that it is effectively to distribute the load implant suffered, especially to reduce the stress generated by the lateral load when the first molar implant has a small contact with its adjacent teeth

An Action Study on Morning Reading Activity on Campus Among College English Learners

Having gone through fierce competition and standardized university entrance exam, most of the undergraduates are conversant at English reading and listening, but by and large weak at speaking and writing. At present, there is still considerable room for improvement in English speaking training in the university of China. For instance, students in mounting numbers become nonchalant about improving their speaking on account of the fear of making mistakes, the pronunciation mistakes “fossilization”, the lack of intrinsic motivation and confidence in expression, the scarcity of professional oral English trainees and all-in English environment for students to immerge themselves in. However, as is universally acknowledged, speaking skill should be given more priority in an era of globalization and intercultural communication which is gaining paces. Thus, teachers should try their utmost to prepare students better for their future study and provide them with more opportunities to see and explore the world with no obstacles in language.As the online study goes viral and the vibrant and fast upgradation and innovation of learning method speed up, the factors contributing to student’s learning motivation have subjected to great change. Thus, it is necessary to analyze and delve into the current research condition and future possibilities. Besides, in general, the study on the English learning motivation of undergraduates in China still stays at superficial level and its major contents and principles are applied and fabricated, leading to the lack of features of the time and creativity. This paper is going to put emphasis on and analyze “Morning Reading Activity” on campus, focusing on improving speaking ability of university students based on the past learning and teaching experience and researches. This article is designed to expound on English speaking learning and training in details by the following two questions: (1) How to apply affective filter hypothesis put forward by Steven Krashen in speaking activity? (2) How to exercise motivation principle in the activity

Research on Internet Technology Innovation and Information Security Challenges in New Vehicle Energy Sector

With the rapid proliferation and advancement of new energy vehicles, Internet technology has garnered significant attention and application in this field. This study focuses on innovations in Internet technology in the domain of new automotive energy and the associated information security challenges. The innovations in Internet technology relevant to new energy vehicles, including Telematics, intelligent driving, and remote control, are initially explored. Subsequently, the information security challenges brought about by these innovations are analyzed, encompassing various aspects such as data privacy breaches, remote attacks, and malware infections. The significance of information security in the development of new energy vehicles is emphasized. Solutions and suggestions, including the strengthening of encryption technology, the establishment of a robust security framework, and the enhancement of user education and awareness, are put forward. In conclusion, the current state of research on Internet technology innovation and information security challenges is summarized, and it is suggested that future research should delve deeper into the trajectory of Internet technology development in the field of new energy vehicles, along with the attendant information security challenges, to provide theoretical and practical support for promoting the healthy development and secure application of the new energy vehicle industry