Arctic University of Norway


Arctic University of Norway

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Polanco G.,Arctic University of Norway
2016 International Symposium on Small-Scale Intelligent Manufacturing Systems, SIMS 2016 | Year: 2016

Review on control process studies and teaching methods shows that majority of the scenarios presented and discussed correspond to restricted operation conditions. So, wider and deeper understanding of the interaction between different variables of the actual system is required in order to enhanced the knowledge of new professionals. This work presents the fluid interaction of three flow streams and their characteristics inside a continuous stirred heated tank (CSHT) when it is assumed that characteristics at the exit stream are the same as the characteristics inside the CSHT. Novelty of this work is fact that all four variables: temperature, composition, liquid level inside the tank and mass flow are considered simultaneously for the three streams. Model combines all three governing equations; mass, species and energy conservation laws, for a constant section area tank using MatLab Simulink ®. Discharge velocity follows Torricelli's law. Model main constrains is defined by the assumption of having density and specific heat capacity as constants. The behaviour of the system can be determined successfully by the developed model. Interconnected temperature, exit mass flow, volume and concentration are determined. © 2016 IEEE.

Mustafa M.Y.,Arctic University of Norway
2016 International Symposium on Small-Scale Intelligent Manufacturing Systems, SIMS 2016 | Year: 2016

The design of the fuel cell plays a major role in determining their cost. It is not only the cost of materials that increases the cost of the fuel cell, but also the manufacturing techniques and the need for skilled technicians for assembling and testing the fuel cell while manufacturing. The main aim of this work is to present a conceptual design of a fuel cell with the purpose of reducing the cost of production through using conventional materials and more effective production techniques, then testing the fuel cell to validate its performance. Small-scale intelligent manufacturing system (SIMS) can be associated with the proposed concept to reduce the cost of the fuel cell. © 2016 IEEE.

Polanco G.,Arctic University of Norway
ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) | Year: 2016

Currently teaching challenges involve incorporation of new technologies or approaches to address teaching/learning process of students more attracted to technology than before. Additionally, the possibility of having student trough internet demands the use of new technological techniques in order to deliver required concepts in a successful way, especially in those cases where a practical application is involved. This work presents a computer model of the "Heat pump system" equipment located at UiT, The Artic University of Norway - Campus Narvik. This system contains the typical elements in a refrigeration system as a compressor, an evaporator, a condenser, an expansion valve, two filters and a visor. The working fluid inside the refrigerant system is Chlorodifluoromethane (CHClF2) frequently known as refrigerant R22, meanwhile the contraflow fluid in the heat exchanger is water. Golden factor of having experimental facility is the fact that the phenomenon will occur as it is, without any theoretical considerations or assumptions. So, when merging both technology and actual equipment, concepts and definitions can be demonstrated by experimental activities and also the models frequently used can be compared to the actual parameters behaviour. For instance, relation between thermodynamics properties and the mechanical variables as compressor power can be described based on the functioning of the equipment, but the realistic application of isentropic functioning of the compressor can be contrasted against the actual compressor performance, or the isobaric assumption on the heat exchanger can be compared against the heat exchanger working at particular conditions. Refrigeration cycle theoretical computer model can be built based on pressure values before and after the compressor as well as the temperatures at key points, however, actual system will have a complete set of parameter values at different location. Comparing both theoretical and actual cycles on pressure-temperature graph, efficiency of the model can be obtained in an interactive way. In this way, teaching activities will cover the necessary development of analytical thinking about the applicability of different models in different engineering application trough out a refrigeration case. Moreover computer model technique also introduces the possibility of expansion the range of possible refrigerant fluids, which can be tested without compromise the safety of the students when the materials or fluids involved could be considered as hazardous. The presented computer model includes the use of computational tool called PRODE® to calculate the properties of the flow. As result, an interactive computer model was developed as an extra help within the teaching/learning process. Copyright © 2016 by ASME.

Myhre J.N.,Arctic University of Norway | Kampffmeyer M.,Arctic University of Norway | Jenssen R.,Arctic University of Norway
ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings | Year: 2017

The density ridge framework for estimating principal curves and surfaces has in a number of recent works been shown to capture manifold structure in data in an intuitive and effective manner. However, to date there exists no efficient way to traverse these manifolds as defined by density ridges. This is unfortunate, as manifold traversal is an important problem for example for shape estimation in medical imaging, or in general for being able to characterize and understand state transitions or local variability over the data manifold. In this paper, we remedy this situation by introducing a novel manifold traversal algorithm based on geodesics within the density ridge approach. The traversal is executed in a subspace capturing the intrinsic dimensionality of the data using dimensionality reduction techniques such as principal component analysis or kernel entropy component analysis. A mapping back to the ambient space is obtained by training a neural network. We compare against maximum mean discrepancy traversal, a recent approach, and obtain promising results. © 2017 IEEE.

Piatnitski A.,Arctic University of Norway | Piatnitski A.,Russian Academy of Sciences | Ptashnyk M.,University of Dundee
Multiscale Modeling and Simulation | Year: 2017

In this paper homogenization of a mathematical model for plant tissue biomechanics is presented. The microscopic model constitutes a strongly coupled system of reaction-diffusionconvection equations for chemical processes in plant cells, the equations of poroelasticity for elastic deformations of plant cell walls and middle lamella, and Stokes equations for fluid flow inside the cells. The chemical process in cells and the elastic properties of cell walls and middle lamella are coupled because elastic moduli depend on densities involved in chemical reactions, whereas chemical reactions depend on mechanical stresses. Using homogenization techniques, we derive rigorously a macroscopic model for plant biomechanics. To pass to the limit in the nonlinear reaction terms, which depend on elastic strain, we prove the strong two-scale convergence of the displacement gradient and velocity field. © 2017 Society for Industrial and Applied Mathematics.

Mustafa A.,Arctic University of Norway | Calay R.K.,Arctic University of Norway | Mustafa M.Y.,Arctic University of Norway
Energy Procedia | Year: 2017

A techno-economic feasibility study of liquid bio-fuel production from biomass to meet the demand for public transport in small communitiesis presented. The methodology adopted in this work is based on calculating the demand of fuels required by transport sector and then estimating the amount of available biomass from various sources which can be treated to produce bio-fuels to meet the demand within the region. Depending on demand and available biomass feedstock, size and type of the gasification plant are specified. Narvik, a town in the northern part of Norway, is considered as a case study. The current demand of diesel for public transport in Narvik was calculated. The main sources of biomass in the region under consideration come basically from forests and municipal solid waste. It was found out that the potential of producing biofuel is more than three times the fuel demand for public transport, which means that excess biofuel produced can be used in other sectors such as heating. A downdraft gasifier of 6.0 MW was considered adequate to produce the required amount of biofuel. Cost analysis was performed where capital cost, operational and maintenance (O&M) costs for the biomass pre-treatment processes, the gasification plant and the gas to liquid (GTL) plant were considered in the assessment. It was concluded that the payback period of the project could be achieved within four years. The study demonstrated that biomass gasification offers small communities a means to cover their energy demand for public transport using local biomass feedstock and fulfils environmental targets of the community. © 2017 The Authors.

Karterud H.N.,University of Oslo | Risor M.B.,Arctic University of Norway | Haavet O.R.,University of Oslo
Seizure | Year: 2015

Purpose: This qualitative study explored the impact of using a biopsychosocial approach to explain the diagnosis of non-epileptic seizures (NES). Methods: Semi-structured interviews of eleven adolescents and young adults who had participated in an inpatient follow-up stay of the diagnosis were used. The interviews were taped, transcribed, and analysed using systematic text condensation. Results: Three key themes were identified: 1. "Threatened self-image": Patients initially perceived their diagnosis as being purely psychological. As they did not accept that they had mental disorders, they interpreted this as frightening and threatening, and resisted the diagnosis. 2. "Being believed and belief in oneself": Participants had many experiences of being suspected by healthcare providers of staging their seizures. Some had even begun to have doubts themselves as to whether the attacks were voluntary or not. Explaining that unconscious processes are involved in NES contributed towards increasing patients' feelings of being believed, and thereby acceptance of the diagnosis. 3. "Getting an explanation that makes sense": Some participants identified connections between their personal histories and their seizures and became seizure-free. Others found that the explanatory models gave personal meaning, but did not become seizure-free, while a few continued to doubt whether NES was the correct diagnosis. Conclusion: Being believed was the most elemental factor for coping with the condition. Using a biopsychosocial approach to explain the diagnosis may facilitate identification with the explanatory models, and thus acceptance of the diagnosis. © 2014 Published by Elsevier Ltd on behalf of British Epilepsy Association.

Silsand L.,University Hospital of Northern Norway | Ellingsen G.,Arctic University of Norway
Proceedings of the ACM Conference on Computer Supported Cooperative Work, CSCW | Year: 2016

Clinical Decision Support (CDS) Systems are considered crucial for diagnosis, treatment and care of patients. However, practical benefits of such systems have been far below expectations. This paper explores how the evolving interdependencies in organizational, clinical, political, and behavioral terms influence the design and implementation of CDS. The paper discusses how these interdependencies complicate clinical use of CDS where cross-departmental patient pathways increasingly dominate approaches to dealing with patients with complex conditions. Empirically, we report from an acute geriatric patient pathway project. The aim was to design and implement a decision-support form for triage of elderly patients in the emergency unit. The study emphasizes the intertwined collaborative nature of healthcare work, and the resulting need to consider the whole context when designing and implementing CDS tools. The contribution is to emphasize the "extended design" perspective to capture how workplace technologies and practices are shaped across multiple contexts and prolonged periods. © 2016 ACM.

Fisheries operate under fluctuating environmental conditions, targeting fish stocks that appear in varying densities in different areas, often with abrupt and unexpected local changes. Physical conditions, markets and management regulations constrain vessels in different and varying ways. These factors all contribute to forming the fleet diversity we find in most fisheries. Here, a simulation model of the Northeast Arctic cod fishery is used in order to investigate how this diversity is formed and maintained, assuming rational economic behaviour under varying combined constraints. The study also focuses on how the ability of vessels to find fish influences fleet diversity, profitability, stock development and seasonal profiles of the fishery. Results indicate that an increased ability to target the most profitable fishing grounds may influence fleet diversity positively or negatively, depending on overall exploitation level. High exploitation rates also increase the temporal fluctuations in fleet diversity and profits, which are amplified as the fish-finding ability increases. © 2016 Eide.

Ellingsen G.,Arctic University of Norway
Advances in Intelligent Systems and Computing | Year: 2015

For several years, telemedicine practitioners have struggled to establish their field as an autonomous scientific discipline, which is often reflected in diverging definitions of what telemedicine is. However, the telemedicine community depends on and draws heavily on established scientific areas such as medicine, economics, informatics and social science, which each have their own criteria for good scientific work. In addition, new technological innovations appear to pave the way for new applications within the field, thus challenging perceptions of what the field encompasses. The aim of this paper is to contribute to this debate by conceptualizing the notion of telemedicine as being something people do rather than numerous definitions of what the field is. © Springer International Publishing Switzerland 2015.

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