Time Series Imputation via L1 Norm-Based Singular Spectrum Analysis

Missing values in time series data is a well-known and important problem which many researchers have studied extensively in various fields. In this paper, a new nonparametric approach for missing value imputation in time series is proposed. The main novelty of this research is applying the L1 norm-based version of Singular Spectrum Analysis (SSA), namely L1-SSA which is robust against outliers. The performance of the new imputation method has been compared with many other established methods. The comparison is done by applying them to various real and simulated time series. The obtained results confirm that the SSA-based methods, especially L1-SSA can provide better imputation in comparison to other methods

Designing for oral storytelling practices at home: A parental perspective

Storytelling at home is typically an oral practice that supports parents and children to make sense of their family identity. Parents play a key role in crafting the story plot and facilitating the child’s participation in the storytelling process. Yet in the context of digital technology, interaction design researchers have tended to focus on children and how digital storytelling tools can support them in their learning. Adopting a “family lens” the aim of this research is to understand the character of oral storytelling practice and identify opportunities for digital storytelling design. The findings outline a co-design workshop that involved a team of designers and parents, who regularly engaged in oral storytelling. Grounded in a systematic video analysis of the workshop alongside a reflection of the design decisions that unfolded, we contribute four new design opportunities centring on the themes of flexibility, shared experience, minimalism, and autobiographical memories. These opportunities can guide interaction design researchers interested in designing new digital oral storytelling tools for families

Mandelbrot- and Julia-like Rendering of Polynomiographs

Polynomiography is a method of visualization of complex polynomial root finding process. One of the applications of polynomiography is generation of aesthetic patterns. In this paper, we present two new algorithms for polynomiograph rendering that allow to obtain new diverse patterns. The algorithms are based on the ideas used to render the well known Mandelbrot and Julia sets. The results obtained with the proposed algorithms can enrich the functionality of the existing polynomiography software

An ontology-based tool for automated configuration and deployment of technical building management services

In this work we present the architecture and a reference implementation of a software tool to automate the configuration and deployment of services for fault detection and diagnosis which can assist to improve operational building performance. We use an ontology as an intermediate meta-data layer to integrate the BIM information and the static BMS data required to automate this process. The contribution aspect resides in the demonstration of the approach which is based on the core concept of a tailored pairing of a fault detection and diagnosis service and an ontology query specifically designed by experts. Suggestions for the architecture are provided on how to embed the ontology in the overall framework. We present results from a first prototype to detect faults in real trend data of an air handling unit using rule-based analytics

Experimental investigation on the effect of wear flat inclination on the cutting response of a blunt tool in rock cutting

A vast majority of experimental researches focuses on the cutting action of a sharp cutter, while there has been limited experimental work devoted to the study of the contact process at the wear flat-rock interface. The specific objective of this study is to determine the effect of the wear flat inclination angle ( β ) with respect to the cutter velocity vector ( vv ) on both the contact stress ( σ ) and friction coefficient ( μ ) mobilized at the wear flat-rock interface. An extensive and comprehensive set of cutting experiments was carried out on thirteen different sedimentary quarry rock samples using a state-of-the-art rock cutting equipment. A unique cutter holder was purposely designed and manufactured along with a precise experimental protocol implemented in order to change the back rake angle and therefore the inclination β by steps of 0.10∘ . The experimental observations confirm the existence of three regimes of frictional contact (identified as elastic, elasto-plastic and plastic) for all rock samples. Further, the results suggest that the scaled contact stress is predominantly controlled by a dimensionless number η=E∗tanβq with E∗ the plane strain elastic modulus and q the rock strength

Differential Methylation of the HPV 16 Upstream Regulatory Region during Epithelial Differentiation and Neoplastic Transformation

High risk human papillomaviruses are squamous epitheliotropic viruses that may cause cervical and other cancers. HPV replication depends on squamous epithelial differentiation. Transformation of HPV-infected cells goes along with substantial alteration of the viral gene expression profile and preferentially occurs at transformation zones usually at the uterine cervix. Methylation of the viral genome may affect regulatory features that control transcription and replication of the viral genome. Therefore, we analyzed the methylation pattern of the HPV16 upstream regulatory region (URR) during squamous epithelial differentiation and neoplastic transformation and analyzed how shifts in the HPV URR methylome may affect viral gene expression and replication. HPV 16 positive biopsy sections encompassing all stages of an HPV infection (latent, permissive and transforming) were micro-dissected and DNA was isolated from cell fractions representing the basal, intermediate, and superficial cell layers, each, as well as from transformed p16INK4a-positive cells. We observed fundamental changes in the methylation profile of transcription factor binding sites in the HPV16 upstream regulatory region linked to the squamous epithelial differentiation stage. Squamous epithelial transformation indicated by p16INK4a overexpression was associated with methylation of the distal E2 binding site 1 leading to hyper-activation of the HPV 16 URR. Adjacent normal but HPV 16-infected epithelial areas retained hyper-methylated HPV DNA suggesting that these viral genomes were inactivated. These data suggest that distinct shifts of the HPV 16 methylome are linked to differentiation dependent transcription and replication control and may trigger neoplastic transformation

Polynomials over quaternions and coquaternions: a unified approach

This paper aims to present, in a unified manner, results which are valid on both the algebras of quaternions and coquaternions and, simultaneously, call the attention to the main differences between these two algebras. The rings of one-sided polynomials over each of these algebras are studied and some important differences in what concerns the structure of the set of their zeros are remarked. Examples illustrating this different behavior of the zero-sets of quaternionic and coquaternionic polynomials are also presented.(undefined)info:eu-repo/semantics/publishedVersio

A Survey of Air-to-Ground Propagation Channel Modeling for Unmanned Aerial Vehicles

In recent years, there has been a dramatic increase in the use of unmanned aerial vehicles (UAVs), particularly for small UAVs, due to their affordable prices, ease of availability, and ease of operability. Existing and future applications of UAVs include remote surveillance and monitoring, relief operations, package delivery, and communication backhaul infrastructure. Additionally, UAVs are envisioned as an important component of 5G wireless technology and beyond. The unique application scenarios for UAVs necessitate accurate air-to-ground (AG) propagation channel models for designing and evaluating UAV communication links for control/non-payload as well as payload data transmissions. These AG propagation models have not been investigated in detail when compared to terrestrial propagation models. In this paper, a comprehensive survey is provided on available AG channel measurement campaigns, large and small scale fading channel models, their limitations, and future research directions for UAV communication scenarios