Search results for "mathematics"

The effect of visual motion stimulus characteristics on vection and visually induced motion sickness

2019

Abstract Several factors contribute to the likelihood of experiencing illusory sensations of self-motion (i.e., vection) in Virtual Reality (VR) applications. VR users can also experience adverse effects such as disorientation, oculomotor issues, or nausea known as visually induced motion sickness (VIMS). The goal of the present study was to systematically investigate three characteristics of visual motion stimuli—speed, density, and axis of rotation—and how they relate to both vection and VIMS. Two experiments were conducted. In Experiment 1, a stereoscopic stimulus containing a star field of white spheres on a black background was presented to 21 participants. The stimulus contained linea…

Cultivation of 3D Dermal Tissue by Application of Autologous Matrix

2020

Abstract The most common reasons for major skin loss are thermal trauma — burns and scalds that can result in rapid, extensive, deep wounds as well as chronic non-healing wounds. Treatment using common techniques is poor and depending on the trauma level can result in death. There is a substantial need for skin integrity restoration. The main goal of this study was to develop an autologous 3D skin model that could eventually be translated into clinical applications. The study examined a variety of factors — extracellular matrix components, cell count, culture medium modification and role of structurally and functionally high-quality 3D skin dermis layer tissue culture production. The result…

2019

Foam rolling is thought to improve muscular performance and flexibility as well as to alleviate muscle fatigue and soreness. For this reason, foam rolling has become a popular intervention in all kinds of sport settings used to increase the efficiency of training or competition preparation as well as to speed post-exercise recovery. The objective of this meta-analysis was to compare the effects of foam rolling applied before (pre-rolling as a warm-up activity) and after (post-rolling as a recovery strategy) exercise on sprint, jump, and strength performance as well as on flexibility and muscle pain outcomes and to identify whether self-massage with a foam roller or a roller massager is more…

A solution of the minimum-time velocity planning problem based on lattice theory

2018

For a vehicle on an assigned path, we find the minimum-time speed law that satisfies kinematic and dynamic constraints, related to maximum speed and maximum tangential and transversal acceleration. We present a necessary and sufficient condition for the feasibility of the problem and a simple operator, based on the solution of two ordinary differential equations, which computes the optimal solution. Theoretically, we show that the problem feasible set, if not empty, is a lattice, whose supremum element corresponds to the optimal solution.

Networks Describing Dynamical Systems

2018

Abstract We consider systems of ordinary differential equations that arise in the theory of gene regulatory networks. These systems can be of arbitrary size but of definite structure that depends on the choice of regulatory matrices. Attractors play the decisive role in behaviour of elements of such systems. We study the structure of simple attractors that consist of a number of critical points for several choices of regulatory matrices.

GPU-Based Optimisation of 3D Sensor Placement Considering Redundancy, Range and Field of View

2020

This paper presents a novel and efficient solution for the 3D sensor placement problem based on GPU programming and massive parallelisation. Compared to prior art using gradient-search and mixed-integer based approaches, the method presented in this paper returns optimal or good results in a fraction of the time compared to previous approaches. The presented method allows for redundancy, i.e. requiring selected sub-volumes to be covered by at least n sensors. The presented results are for 3D sensors which have a visible volume represented by cones, but the method can easily be extended to work with sensors having other range and field of view shapes, such as 2D cameras and lidars.

Reinforcement learning in synthetic gene circuits.

2020

Synthetic gene circuits allow programming in DNA the expression of a phenotype at a given environmental condition. The recent integration of memory systems with gene circuits opens the door to their adaptation to new conditions and their re-programming. This lays the foundation to emulate neuromorphic behaviour and solve complex problems similarly to artificial neural networks. Cellular products such as DNA or proteins can be used to store memory in both digital and analog formats, allowing cells to be turned into living computing devices able to record information regarding their previous states. In particular, synthetic gene circuits with memory can be engineered into living systems to al…

Discovering unbounded unions of regular pattern languages from positive examples

1996

The problem of learning unions of certain pattern languages from positive examples is considered. We restrict to the regular patterns, i.e., patterns where each variable symbol can appear only once, and to the substring patterns, which is a subclass of regular patterns of the type xαy, where x and y are variables and α is a string of constant symbols. We present an algorithm that, given a set of strings, finds a good collection of patterns covering this set. The notion of a ‘good covering’ is defined as the most probable collection of patterns likely to be present in the examples, assuming a simple probabilistic model, or equivalently using the Minimum Description Length (MDL) principle. Ou…

Influence of label and location of testing on acceptability of cream cheese varying in fat content

1995

The acceptability of low-, medium- and high-fat versions of a cream cheese to consumers was measured in different conditions by rating overall distance from ideal. The influence of label (unlabelled vs. commercial package) differed according to the cream cheese fat-level habits of the assessors and to the fat level of the product. In labelled testing, high-fat cream cheese was more highly accepted by high- and medium-fat users and low-fat cream cheese seemed to be further from ideal for high-fat users. The location of testing (home vs. laboratory) affected the rating of only the high-fat product: consumers are more severe on it at home than in the laboratory.

“Is there any sugar in bread?” A qualitative video analysis of student activating learning tasks in Home Economics

2021

The Norwegian Food and Health (FH) school subject aims to develop students' ability to understand the association between diet and health. Research on FH in Norway indicates that the main focus today is on cooking and the development of practical cooking skills, leaving little emphasis on activities related to the more theoretical aspects of the curriculum. To increase students’ knowledge and skills regarding nutrition and health, we aimed to evaluate three newly developed student-activating learning tasks. Three 6th grade FH classes in Southern Norway participated. Audio and video recording of the learning tasks were used to evaluate the activities. Also, data from focus group discussions …