Narvik University College is a state-owned university college in the town of Narvik, Norway. Established 1 August 1994, HiN has approximately 2000 students and 220 employees. The university college is divided into the Department of Technology and the Department of Health and Society. Narvik University College offers bachelor's degrees in nursing, business and administration as well as engineering, and various master's degrees in Technology. It also offers a PhD in technology. Wikipedia.
Laksa A.,Narvik University College
AIP Conference Proceedings | Year: 2015
B-splines are the de facto industrial standard for surface modelling in Computer Aided design. It is comparable to bend flexible rods of wood or metal. A flexible rod minimize the energy when bending, a third degree polynomial spline curve minimize the second derivatives. B-spline is a nice way of representing polynomial splines, it connect polynomial splines to corner cutting techniques, which induces many nice and useful properties. However, the B-spline representation can be expanded to something we can call general B-splines, i.e. both polynomial and non-polynomial splines. We will show how this expansion can be done, and the properties it induces, and examples of non-polynomial B-spline. © 2015 AIP Publishing LLC.
Pettersson A.I.,Lulea University of Technology |
Pettersson A.I.,Ericsson AB |
Segerstedt A.,Lulea University of Technology |
Segerstedt A.,Narvik University College
International Journal of Production Economics | Year: 2013
Organisations focus on reducing costs in their supply chains to increase net income. In order to reduce costs a company needs to know how to measure Supply Chain Cost (SCC). This paper is concerned with SCC and how measurements of SCC are and can be used in industry. The paper describes a suggested model for measuring SCC. Representatives from 30 companies in 10 different business sectors are interviewed about how they measure costs in their supply chains compared against this model. The focus is also on identifying the difference between SCC based on estimated standard cost compared to actual cost. A case study describes and shows the difference between measuring SCC based on calculated standard cost and measuring it based on actual cost. Our studies show that general thorough cost and supply chain analyses in many companies can be improved and further developed. © 2012 Elsevier B.V. All rights reserved.
Antypas K.,University of Tromsø |
Wangberg S.C.,Narvik University College |
Wangberg S.C.,Regional University of the North
Journal of Medical Internet Research | Year: 2014
Background: An increase in physical activity for secondary prevention of cardiovascular disease and cardiac rehabilitation has multiple therapeutic benefits, including decreased mortality. Internet- and mobile-based interventions for physical activity have shown promising results in helping users increase or maintain their level of physical activity in general and specifically in secondary prevention of cardiovascular diseases and cardiac rehabilitation. One component related to the efficacy of these interventions is tailoring of the content to the individual. Objective: Our trial assessed the effect of a longitudinally tailored Internet- and mobile-based intervention for physical activity as an extension of a face-to-face cardiac rehabilitation stay. We hypothesized that users of the tailored intervention would maintain their physical activity level better than users of the nontailored version. Methods: The study population included adult participants of a cardiac rehabilitation program in Norway with home Internet access and a mobile phone. The participants were randomized in monthly clusters to a tailored or nontailored (control) intervention group. All participants had access to a website with information regarding cardiac rehabilitation, an online discussion forum, and an online activity calendar. Those using the tailored intervention received tailored content based on models of health behavior via the website and mobile fully automated text messages. The main outcome was self-reported level of physical activity, which was obtained using an online international physical activity questionnaire at baseline, at discharge, and at 1 month and 3 months after discharge from the cardiac rehabilitation program. Results: Included in the study were 69 participants. One month after discharge, the tailored intervention group (n=10) had a higher median level of overall physical activity (median 2737.5, IQR 4200.2) than the control group (n=14, median 1650.0, IQR 2443.5), but the difference was not significant (Kolmogorov-Smirnov Z=0.823, P=.38, r=.17). At 3 months after discharge, the tailored intervention group (n=7) had a significantly higher median level of overall physical activity (median 5613.0, IQR 2828.0) than the control group (n=12, median 1356.0, IQR 2937.0; Kolmogorov-Smirnov Z=1.397, P=.02, r=.33). The median adherence was 45.0 (95% CI 0.0-169.8) days for the tailored group and 111.0 (95% CI 45.1-176.9) days for the control group; however, the difference was not significant (P=.39). There were no statistically significant differences between the 2 groups in stage of change, self-efficacy, social support, perceived tailoring, anxiety, or depression. Conclusions: Because of the small sample size and the high attrition rate at the follow-up visits, we cannot make conclusions regarding the efficacy of our approach, but the results indicate that the tailored version of the intervention may have contributed to the long-term higher physical activity maintained after cardiac rehabilitation by participants receiving the tailored intervention compared with those receiving the nontailored intervention. © Holly O Witteman.
Schlanbusch R.,Narvik University College |
Loria A.,Supelec |
Nicklasson P.J.,Narvik University College
Automatica | Year: 2012
We study attitude control of rigid bodies on quaternion coordinates under three mathematically different perspectives, depending on how the system dynamics are assumed to evolve. In the first case, we suppose that one equilibrium point is chosen a priori and a continuous controller is used under the assumption that the rigid body always spins in the same direction. In the second case, we relax the assumption that the sense of rotation is constant. Finally, a third scenario is considered in which hybrid (switching) control is used to choose the direction in which to spin, that is, both equilibria are continuously considered with regard to less energy consumption. It is showed that each of three scenarios must be treated in a different theoretical setting. A comparative study in simulations is also provided. © 2012 Elsevier Ltd. All rights reserved.
McClusky L.M.,Narvik University College
Reproduction | Year: 2013
The severe degenerative phenomena that characterises spermatogenesis in mating blue sharks involves spatially separated germ cell and Sertoli cell apoptosis. Unlike that observed in multilayered type B spermatogonial and spermatocyte cysts caspase-3-dependent apoptosis of single and multinucleate type B spermatogonia in one to three spermatogonial layered cysts resulted in their complete fragmentation, delayed phagocytic removal and displacement of the apoptotic bodies towards the perilumenar Sertoli nuclei. Changes were observed in the immunostaining patterns of proliferating cell nuclear antigen (PCNA), including subtle changes in cytoplasmic and overall intense immunostaining, labelled single and multinucleate cell (MNC) apoptotic spermatogonial masses in premeiotic cysts in different stages of the protracted death process. Initial massive MNC formation at the mitosis-meiosis transition eventually left its imprint in the spermatogenic sequence in the form of vacuolated areas in the affected and subsequent stages. Some of the latter attempted further developmental advance but eventually degenerated. The observed higher PCNA index of spermatogonia in vacuolated testes compared to testes with the MNC type of degeneration indicated that the former testicular morphology represented, in essence, the recovery phase from the pronounced MNC death earlier. Events culminating in the eventual apoptotic demise of the Sertoli cells themselves included the abortion of further development (presumably due to a suboptimal Sertoli:germ cell ratio) of those germ cells left over from the wave of MNC death that swept the cysts. Eventually the Sertoli-cell-only cysts became apoptotic as they were engulfed by the infiltrating lymphomyeloid cells from the epigonal organ associated with the mature pole of the testis. © 2013 Society for Reproduction and Fertility.
Polanco G.,Simon Bolivar University of Venezuela |
Holdo A.E.,Narvik University College |
Munday G.,Coventry University
Journal of Hazardous Materials | Year: 2010
The major concern on the management of superheated liquids, in industrial environments, is the large potential hazards involved in cases of any accidental release. There is a possibility that a violent phase change could take place inside the fluid released generating a flashing jet. This violent phase change might produce catastrophic consequences, such as explosions, fires or toxic exposure, in the installations and in the surroundings. The knowledge and understanding of the mechanisms involved in those releases become an important issue in the prevention of these consequences and the minimization of their impact. This work presents a comprehensive review of information about flashing processes. The review begins with a description of the single phase jet followed by a description of the two-phase flashing jet. The concepts and implications of the thermodynamic and mechanical effects on the behaviour of the jets are considered at the beginning of the review. Following the review is devoted to the classification of the different study approaches used to understand flashing processes in the past, highlighting various critical parameters on the behaviour and the hazard consequences of flashing jets. The review also contains an extensive compilation of experimental, theoretical and numerical data relating to these phenomena, which includes information on the distinct characteristics of the jet, since type of jet, velocity distribution, expansion angle and mass phase change all require individual estimation. © 2009 Elsevier B.V. All rights reserved.
Mcclusky L.M.,Narvik University College
Journal of Morphology | Year: 2011
The elasmobranch testis consists of spherical spermatocysts, each housing a single germ cell stage and its own clone of Sertoli cells. Because of the simple diametrical arrangement of cysts in maturational order, the testes of Squalus acanthias, Scyliorhinus canicula, and Prionace glauca are classified as the diametric shark testis type. The aim of this study was to document histologically the spermatocyst composition in the blue shark stage-by-stage and to establish whether the diametric testis type confers any uniformity regarding the expression of spermatogenesis in all sharks with this testis type. Analysis of the testes of blue sharks breeding in summer revealed extensive cyst degeneration of various forms and degrees, cyst shrinkage, and cyst disorganization with or without evidence of cell death, initially at the spermatogonia-spermatocyte transition but predominantly in spermatocyte and spermatid cysts. Animals could be grouped into two categories based on the major degenerative phenomena observed, namely those with extensive multinucleate cell (MNC) formation, and those with pronounced vacuolation in cysts. A major finding was the significant (P < 0.001) predominance of MNC formation and vacuolation in late-stage spermatogonial cysts in the respective categories of sharks. Spermatocyte cysts showed varying degrees of germ cell depletion, with or without evidence of degeneration. Normal-looking, but clearly subnormal-sized primary and secondary spermatocyte cysts with no evidence of degeneration were significantly the dominant spermatocyte cyst types in both categories. It is proposed that these subnormal-sized spermatocyte cysts could proceed into spermiogenesis. Because neighboring spermatid cysts lacked ordered bundling of spermatid heads (disorganized), a morphology significantly correlated with the vacuolation category of sharks, these results suggest that further progression into spermiogenesis was halted in such cysts. Thus, testicular degeneration in the diametric testis type is species specific in quantity and quality. © 2011 Wiley-Liss, Inc.
McClusky L.M.,Narvik University College
Cell and Tissue Research | Year: 2012
A common observation in the vertebrate testis is that new germ cell clones enter spermatogenesis proper before previously formed clones have completed their development. The extent to which the developmental advance of any given germ cell clone in any phase of spermatogenesis is dependent on that of neighboring clones and/or on the coordinating influence of associated Sertoli cells in the immediate vicinity or of others further away remains unclear. This review presents an overall synthesis of findings in an ancient vertebrate, the spiny dogfish shark and shows that, even at this phyletic level, the developmental advance of a given germ cell clone is the outcome of various processes emanating from its spatiotemporal relationship with (1) its own complement of Sertoli cells in the anatomically distinct spermatocyst and (2) Sertoli cells associated with other germ cell clones that lie upstream or downstream in the spermatogenic progression and that secrete, among others, androgen and estrogen destined for target sites upstream. Analysis of the protracted spermatogenic cycle shows the coordination in space and time of spermatogenic and steroidogenic events. Furthermore, the natural withdrawal of pituitary gonadotropin support in the dogfish causes a distinct and highly ordered gradient of apoptosis among the spermatogonial generations; this in turn is a major contributing factor to the cyclic nature of sperm production observed in this lower vertebrate. Because of the simplicity of their testicular organization, their cystic spermatogenesis and their phylogenetic position, cartilaginous fishes constitute a valid vertebrate reference system for comparative analysis with higher vertebrates. © Springer-Verlag 2012.
Calay R.K.,Narvik University College |
Wang W.C.,Narvik University College
Applied Thermal Engineering | Year: 2013
The present paper presents a high performance cooling/heating ventilation system using a rotary heat exchanger (RHE), together with a reverse-cycle heat pump (RCHP) that can be integrated with various heat sources. Energy consumption in the building sector is largely dominated by the energy consumed in maintaining comfortable conditions indoors. For example in many developed countries the building heating, ventilation and air conditioning (HVAC) systems consume up to 50% of the total energy consumed in buildings. Therefore energy efficient HVAC solutions in buildings are critical for realising CO2 targets at local and global level. There are many heating/cooling concepts that rely upon renewable energy sources and/or use natural low temperature heat sources in the winter and heat sinks in the summer. In the proposed system, waste energy from the exhaust air stream is used to precondition the outdoor air before it is supplied into the building. The hybrid system provides heating in the winter and cooling in the summer without any need for additional heating or cooling devices as required in conventional systems. Its performance is better than a typical reheat or air conditioning system in providing the same indoor air quality (IAQ) levels. It is shown that an energy saving up to 60% (heat energy) is achieved by using the proposed hybrid system in building ventilation applications. © 2013 Elsevier B.V. All rights reserved.
Schlanbusch R.,Narvik University College |
Kristiansen R.,Narvik University College |
Nicklasson P.J.,Narvik University College
Automatica | Year: 2011
In this paper we present a behavioral control solution for reconfiguration of a spacecraft formation using the Null-Space Based (NSB) concept. The solution is task based, and aims to reconfigure and maintain a rigid formation while avoiding collisions between spacecraft. A model of relative translation is derived, together with a passivity-based sliding surface controller which globally stabilizes the equilibrium point of the closed-loop system. The NSB control method is implemented by giving each task different priorities and then calculating desired velocity and a Jacobian matrix for each spacecraft and each task. The velocity vector for each task is then projected into the null-space for higher prioritized tasks to remove conflicting velocity components. Simulation results are presented, showing that each spacecraft moves into the predefined formation without breaking any rules for the higher priority tasks, and all collisions are avoided. © 2011 Elsevier Ltd. All rights reserved.