Aalto University

About: Aalto University is a education organization based out in Espoo, Finland. It is known for research contribution in the topics: Computer science & Context (language use). The organization has 9969 authors who have published 32648 publications receiving 829626 citations. The organization is also known as: TKK & Aalto-korkeakoulu.

Lignin for Nano‐ and Microscaled Carrier Systems: Applications, Trends, and Challenges

Abstract: To liberate society from its dependence on fossil-based fuels and materials it is pivotal to explore components of renewable plant biomass in applications that benefit from their intrinsic biodegradability, safety, and sustainability. Lignin, a byproduct of the pulp and paper industry, is a plausible material for carrying various types of cargo in small- and large-scale applications. Herein, possibilities and constraints regarding the physical-chemical properties of the lignin source as well as modifications and processing required to render lignins suitable for the loading and release of pesticides, pharmaceuticals, and biological macromolecules is reviewed. In addition, the technical challenges, regulatory and toxicological aspects, and future research needed to realize some of the promises that nano- and microscaled lignin materials hold for a sustainable future are critically discussed.

Empirical Study on the Effect of Achievement Badges in TRAKLA2 Online Learning Environment

Abstract: Achievement badges are a form of gamification that can be used to motivate users and to encourage desired actions. In this study, we describe and evaluate the use of achievement badges in the TRAKLA2 online learning environment where students complete interactive, automatically assessed exercises about data structures and algorithms. The students' activity in TRAKLA2 was logged in order to find out whether the achievement badges had an effect on their behavior. We used a between-subject experimental design where the students (N=281) were randomly divided into a treatment and a control group, with and without achievement badges. Students in the treatment group were awarded achievement badges, for example, for solving exercises with only one attempt, returning exercises early, or completing an exercise round with full points. Course grading was similar for both groups, i.e. collecting badges did not affect the final grade. Our results show that achievement badges can be used to affect the behavior of students even when the badges have no impact on the grading. Statistically significant differences in students' behavior were observed with some badge types, while some badges did not seem to have such an effect. We also found that students in the two studied courses responded differently to the badges. Based on our findings, achievement badges seem like a promising method to motivate students and to encourage desired study practices.

A tight connection between gamma-ray outbursts and parsec-scale jet activity in the quasar 3c 454.3

Abstract: We analyze the multi-frequency behavior of the quasar 3C 454.3 during three prominent γ-ray outbursts: 2009 Autumn, 2010 Spring, and 2010 Autumn. The data reveal a repeating pattern, including a triple flare structure, in the properties of each γ-ray outburst, which implies similar mechanism(s) and location for all three events. The multi-frequency behavior indicates that the lower frequency events are co-spatial with the γ-ray outbursts, although the γ-ray emission varies on the shortest timescales. We determine that the variability from UV to IR wavelengths during an outburst results from a single synchrotron component whose properties do not change significantly over the different outbursts. Despite a general increase in the degree of optical linear polarization during an outburst, the polarization drops significantly at the peak of the γ-ray event, which suggests that both shocks and turbulent processes are involved. We detect two disturbances (knots) with superluminal apparent speeds in the parsec-scale jet associated with the outbursts in 2009 Autumn and 2010 Autumn. The kinematic properties of the knots can explain the difference in amplitudes of the γ-ray events, while their millimeter-wave polarization is related to the optical polarization during the outbursts. We interpret the multi-frequency behavior within models involving either a system of standing conical shocks or magnetic reconnection events located in the parsec-scale millimeter-wave core of the jet. We argue that γ-ray outbursts with variability timescales as short as ~3 hr can occur on parsec scales if flares take place in localized regions such as turbulent cells.

Glottal inverse filtering analysis of human voice production — A review of estimation and parameterization methods of the glottal excitation and their applications

Abstract: Glottal inverse filtering (GIF) refers to methods of estimating the source of voiced speech, the glottal volume velocity waveform. GIF is based on the idea of inversion, in which the effects of the vocal tract and lip radiation are cancelled from the output of the voice production mechanism, the speech signal. This article provides a review on GIF research by examining an era spanning five decades during which this topic has been under development. The topic is handled from three main perspectives: the estimation methods of the glottal source, the parameterization techniques that have been developed to express the estimated glottal excitations in numerical forms, and the application areas of GIF. Finally, the strengths and limitations of the GIF approach are discussed.

In search of management accounting theory

Abstract: In this article we discuss management accounting theory. We discuss the motivation for and role of theory in management accounting, arguing that theories in an applied field such as management accounting should provide explanations that are useful for those we study - managers, organizations and society. We evaluate the nature of theories currently used and developed. Those theories that are considered theories by the research community are largely imported from other social sciences, but have hardly anything that makes them unique to management accounting. Those theories that do not currently deserve the status of theory attempt to explain how to apply management accounting to achieve superior performance. We argue that both forms of theories, at present, largely fail to provide valid support for practitioners. We contend that management accounting theory should help us to answer questions of what methods we should apply, how, in what circumstances, and how to change management accounting. We provide suggestions on how management accounting research could proceed to produce better theories.