Search results for "Modeling"
showing 10 items of 4489 documents
Charge Transport Mechanisms in Heavy-Ion Driven Leakage Current in Silicon Carbide Schottky Power Diodes
2016
Under heavy-ion exposure at sufficiently high reverse bias voltages silicon carbide (SiC) Schottky diodes are observed to exhibit gradual increases in leakage current with increasing ion fluence. Heavy-ion exposure alters the overall reverse current-voltage characteristics of these diodes, leaving the forward characteristics practically unchanged. This paper discusses the charge transport mechanisms in the heavy-ion damaged SiC Schottky diodes. A macro model, describing the reverse current-voltage characteristics in the degraded SiC Schottky diodes is proposed. peerReviewed
Two‐sample problems in statistical data modelling
2010
A common problem in mathematical statistics is to check whether two samples differ from each other. From modelling point of view it is possible to make a statistical test for the equality of two means or alternatively two distribution functions. The second approach allows to represent the two‐sample test graphically. This can be done by adding simultaneous confidence bands to the probability‐probability (P — P) or quantile‐quantile (Q — Q) plots. In this paper we compare empirically the accuracy of the classical two‐sample t‐test, empirical likelihood method and several bootstrap methods. For a real data example both Q — Q and P — P plots with simultaneous confidence bands have been plotted…
Splines in convex sets under constraints of two‐sided inequality type in a hyperplane
2008
The problem of minimization of a smoothing functional under inequality constraints is considered in a hyperplane. The conditions of the existence of a solution are obtained and some properties of this solution are investigated. It is proved that the solution is a spline. The method for its construction is suggested. First Published Online: 14 Oct 2010
Social engagement from childhood to middle age and the effect of childhood socio-economic status on middle age social engagement: results from the Na…
2016
ABSTRACTSocial engagement has powerful effects on wellbeing, but variation in individual engagement throughout the lifecourse is wide. The trajectories may differ by gender and be affected by socio-economic status (SES). However, long-term development of social engagement is little studied and the effect of childhood SES on later-life social engagement remains obscure. We aimed to describe the social engagement development from childhood to middle age by gender and test the effect of childhood SES on middle age social engagement. Data (N=16,440, 51.3% male) are drawn from the on-going National Child Development Study, following British babies born in 1958. Social engagement was measured by …
Social Determinants of Success: Social Media, Corporate Governance and Revenue
2019
This study examined how social media (Twitter and LinkedIn) relates to the operating revenue by investigating the effect of the use of social media by the board of directors. To tackle this question, we analyzed the mediating and moderating relationship of social media on the effect of board size in operating revenue (turnover). We studied the implications of the use of social media by the board members by using structural equation modeling (SEM). The data consisted of a random sample of 100 companies listed on the NASDAQ. The study makes two main contributions. First, it shows interesting differences in the use of social media for the operating revenue. Our results suggest that while Twitt…
Network-based indices of individual and collective advising impacts in mathematics
2020
AbstractAdvising and mentoring Ph.D. students is an increasingly important aspect of the academic profession. We define and interpret a family of metrics (collectively referred to as “a-indices”) that can potentially be applied to “ranking academic advisors” using the academic genealogical records of scientists, with the emphasis on taking into account not only the number of students advised by an individual, but also subsequent academic advising records of those students. We also define and calculate the extensions of the proposed indices that account for student co-advising (referred to as “adjusted a-indices”). In addition, we extend some of the proposed metrics to ranking universities a…
ISTehnology – integrated Approach to IS Development and Benefits of its Using
2011
The system ISTechnology and benefits of its usage are analyzed in the paper. ISTechnology provides an integrated approach to business modeling and development of information systems. The system consists of a meta-model and applications. The meta-model enables defining of a platform independent business model of the organization. The applications provide the definition and interpretation of the business model. Interpretation of the business model provides functionality of the information system in the selected platform. The lessons learned confirm that the development and maintenance cost of information systems can be significantly reduced by use of the ISTechnology. The paper describes addi…
Effective Practices in Mitigating Soil Erosion from Fields
2017
Soil erosion by water is a natural process that cannot be avoided. Soil erosion depends on many factors, and a distinction should be made between humanly unchangeable (e.g., rainfall) and modifiable (e.g., length of the field) soil erosion factors. Soil erosion has both on-site and off-site effects. Soil conservation tries to combine modifiable factors so as to maintain erosion in an area of interest to an acceptable level. Strategies to control soil erosion have to be adapted to the desired land use. Knowledge of soil loss tolerance, T, i.e., the maximum admissible erosion from a given field, allows technicians or farmers to establish whether soil conservation practices need to be applied …
Computational Rationality as a Theory of Interaction
2022
Funding Information: This work was funded by the Finnish Center for AI and Academy of Finland (“BAD” and “Human Automata”). We thank our reviewers, Xiuli Chen, Joerg Mueller, Christian Guckelsberger, Sebastiaan de Peuter, Samuel Kaski, Pierre-Alexandre Murena, Antti Keuru-lainen, Suyog Chandramouli, and Roderick Murray-Smith for their comments. Publisher Copyright: © 2022 ACM. How do people interact with computers? This fundamental question was asked by Card, Moran, and Newell in 1983 with a proposition to frame it as a question about human cognition - in other words, as a matter of how information is processed in the mind. Recently, the question has been reframed as one of adaptation: how …
Numerical methods for a nonlinear impact model: A comparative study with closed-form corrections
2011
A physically based impact model-already known and exploited in the field of sound synthesis-is studied using both analytical tools and numerical simulations. It is shown that the Hamiltonian of a physical system composed of a mass impacting on a wall can be expressed analytically as a function of the mass velocity during contact. Moreover, an efficient and accurate approximation for the mass outbound velocity is presented, which allows to estimate the Hamiltonian at the end of the contact. Analytical results are then compared to numerical simulations obtained by discretizing the system with several numerical methods. It is shown that, for some regions of the parameter space, the trajectorie…