Search results for "modelling."
showing 10 items of 1269 documents
Effects of noise on vascular function, oxidative stress, and inflammation: mechanistic insight from studies in mice
2017
Aims Epidemiological studies indicate that traffic noise increases the incidence of coronary artery disease, hypertension and stroke. The underlying mechanisms remain largely unknown. Field studies with nighttime noise exposure demonstrate that aircraft noise leads to vascular dysfunction, which is markedly improved by vitamin C, suggesting a key role of oxidative stress in causing this phenomenon. Methods and results We developed a novel animal model to study the vascular consequences of aircraft noise exposure. Peak sound levels of 85 and mean sound level of 72 dBA applied by loudspeakers for 4 days caused an increase in systolic blood pressure, plasma noradrenaline and angiotensin II lev…
Are There Any Parameters Missing in the Mathematical Models Applied in the Process of Spreading COVID-19?
2021
Simple Summary Nowadays, enhancing development of mathematical models is very important to help in the prediction of coronavirus disease 2019 (COVID1-19). However, the vast majority of published model-based predictions do not cover people who left the epidemic COVID-19 positive (alive) and they must be included in studies to guarantee a more accurate model for application in public health. The epidemic development phenomenon can be obtained with a modelling framework. Abstract On 11 March 2020, coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization (WHO). As of 12.44 GMT on 15 January 2021, it has produced 93,640,296 cases and 2,004,984 deaths. The use …
Subnational mapping of HIV incidence and mortality among individuals aged 15-49 years in sub-Saharan Africa, 2000-18: a modelling study
2021
Background. High-resolution estimates of HIV burden across space and time provide an important tool for tracking and monitoring the progress of prevention and control efforts and assist with improving the precision and efficiency of targeting efforts. We aimed to assess HIV incidence and HIV mortality for all second-level administrative units across sub-Saharan Africa. Methods. In this modelling study, we developed a framework that used the geographically specific HIV prevalence data collected in seroprevalence surveys and antenatal care clinics to train a model that estimates HIV incidence and mortality among individuals aged 15–49 years. We used a model-based geostatistical framework to e…
An exploration of digital ride-hailing multisided platforms' market dynamics: empirical evidence from the Uber case study
2020
PurposeThe purpose of this paper is to experiment a dynamic performance management (DPM) approach to explore and assess the business dynamics of digital ride-hailing platforms with a focus on both supply and demand sides, and related interplays.Design/methodology/approachThe research adopts the DPM framework supported by simulation-based experimentations for developing a systemic case interpretation of Uber Inc. and its specific business complexity.FindingsThe emerging scenario analysis reveals that changes in the commission percentage for drivers and cutting prices for customers (car hailers) by competitors have significant impacts on the car-hailing industry.Originality/valueDPM and assoc…
An Interactive Framework for Offline Data-Driven Multiobjective Optimization
2020
We propose a framework for solving offline data-driven multiobjective optimization problems in an interactive manner. No new data becomes available when solving offline problems. We fit surrogate models to the data to enable optimization, which introduces uncertainty. The framework incorporates preference information from a decision maker in two aspects to direct the solution process. Firstly, the decision maker can guide the optimization by providing preferences for objectives. Secondly, the framework features a novel technique for the decision maker to also express preferences related to maximum acceptable uncertainty in the solutions as preferred ranges of uncertainty. In this way, the d…
Burnout-related ill-being at work : Associations between mindfulness and acceptance skills, worksite factors, and experienced well-being in life
2018
The aim of this paper was to investigate the associations between mindfulness and acceptance (MAA) skills and burnout-related ill-being at work (ILLB) after eliminating the impact of worksite (WS) and general well-being in life (WELLB) factors. The results were derived from data on employees (n = 168) of varying professional backgrounds, who experienced relatively high levels of burnout. Analyses were conducted using structural equation modelling (SEM) and the Cholesky decomposition method, since these allow for the investigation of multiple measures and multiple factors in relation to one another. In relation to ill-being at work, the analyses revealed a general MAA factor as well as a spe…
Developing a framework for using structure-from-motion techniques for road distress applications
2020
On Urban road networks, road agencies need to quickly identify road pavement distresses in order to identify appropriate maintenance and rehabilitation strategies. This is integral as agencies are plagued with financial and time constraint issues. There have been several attempts over the last few years to identify new solutions and techniques to solve these issues. Several of these have shown merit and accuracy in identifying distresses. However, the techniques in many instances are not correlated to available distress identification standards. One of the considered techniques is the use of Structure-from-Motion, which tries to recreate 3D distress models for identification and analysis. T…
Discrete Choice Methods with Simulation
2016
Discrete Choice Methods with Simulation by Kenneth Train has been available in the second edition since 2009. The book is published by Cambridge University Press and is also available for download ...
Using UAV Based 3D Modelling to Provide Smart Monitoring of Road Pavement Conditions
2020
Road pavements need adequate maintenance to ensure that their conditions are kept in a good state throughout their lifespans. For this to be possible, authorities need efficient and effective databases in place, which have up to date and relevant road condition information. However, obtaining this information can be very difficult and costly and for smart city applications, it is vital. Currently, many authorities make maintenance decisions by assuming road conditions, which leads to poor maintenance plans and strategies. This study explores a pathway to obtain key information on a roadway utilizing drone imagery to replicate the roadway as a 3D model. The study validates this by using stru…
Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
AbstractBackgroundTicks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur:IxodesricinusandIxodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change.MethodsWe used species distribution modelling techniques to predict the distributions ofI.ricinusandI.persulcatus,using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Fin…