Søk
Viser treff 41-50 av 88
Location-based analysis and optimization of service network performance: A case study
(Peer reviewed; Book; Chapter, 2018-05-07)
The location problem of service network has been extensively focused by researchers in operational research due to the difficulty in balancing the level of service and efficiency. On the one hand, installing a large number of service facilities within the service network improves availability and responsiveness to customer demands, but it also increases the investment and operating cost. While on ...
Development of Downhole Control Valve
(Master thesis; Mastergradsoppgave, 2018-05-31)
Designing for downhole environment is a challenging process. High pressure and temperature are the main well conditions that effect the design decisions and the tool geometry. Also, the well fluids can obtain high concentration of corrosive content such H2S acid that plays major role in material selection.
The intention of this study is to develop Downhole Control Valve that can be connected to ...
Pointwise estimates for heat kernels of convolution-type operators
(Journal article; Peer reviewed; Tidsskriftartikkel, 2018-04-16)
We study the large‐time behaviour of the fundamental solution of parabolic equations with an elliptic part being non‐local convolution‐type operator. We assume that this operator is a generator of a Markov jump process, and that its convolution kernel decays at least exponentially at infinity. The fundamental solution shows rather different asymptotic behaviour depending on whether | x | ≲ t , or t ...
Review of Icing Effects on Wind Turbine in Cold Regions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-05)
This paper describes a brief overview of main issues related to atmospheric ice accretion on wind turbines installed in cold climate region. Icing has significant effects on wind turbine performance particularly from aerodynamic and structural integrity perspective, as ice accumulates mainly on the leading edge of the blades that change its aerodynamic profile shape and effects its structural dynamics ...
Engineering students' instrumental approaches to mathematics; some positive characteristics
(Journal article; Peer reviewed, 2018)
The present paper presents three deliberately chosen mathematical episodes observed in a class of engineering students taking a basic calculus course. By drawing on analyses of instrumental and relational learning strategies, the episodes are shown to illustrate instrumental approaches indicated by the students. The paper discusses positive characteristics about these approaches while further data ...
Asymptotic Behaviour of Ground States for Mixtures of Ferromagnetic and Antiferromagnetic Interactions in a Dilute Regime
(Journal article; Peer reviewed, 2018-04-30)
We consider randomly distributed mixtures of bonds of ferromagnetic and antiferromagnetic type in a two-dimensional square lattice with probability
1−p
1−p
and p, respectively, according to an i.i.d. random variable. We study minimizers of the corresponding nearest-neighbour spin energy on large domains in
Z
2
Z2
. We prove that there exists
p
0
p0
such that for
p≤
p
0
p≤p0
such ...
Framework for Modeling and Simulation of Household Appliances
(Peer reviewed; Book; Chapter, 2018-12-31)
This paper describes a framework for simulating household appliances in Simulink. Typical Norwegian household equipment have been analyzed based on their characteristic behavior, to establish the requirement for synthesizing and recreating their current waveform, harmonic currents and phase shift. Both detailed simulation of the current waveform and RMS currents for simulation over longer time periods ...
Innvirkninger av distribuert produksjon i svake distribusjonsnett, lokalisert i nordområdene. Hvordan påvirker plusskunder det omkringliggende lavspente distribusjonsnettet.
(Master thesis; Mastergradsoppgave, 2018-08-16)
I denne rapporten har virkninger av plusskunder i svake, lavspente distribusjonsnett blitt undersøkt. Gjennom en informasjonsinnsamling, ble de største utfordringer for fremtidige plusskunder identifisert. Herunder aktuelle teknologier, energiresuser, regelverk og tekniske forhold. Det ble undersøkt hvilke utfordringer et nettselskap kan forvente seg, ved introduksjon av lokal produksjon i et ...
Overview of modern teaching equipment that supports distant learning
(Journal article; Peer reviewed, 2018)
Laboratory is a key element of engineering and
applied sciences educational systems. With the development of
Internet and connecting IT technologies, the appearance of
remote laboratories was inevitable. Virtual laboratories are
also available; they place the experiment in a simulated
environment. However, this writing focuses on remote
experiments not virtual ones. From the students’ point ...
Multi-dimensional Hardy type inequalities in Hölder spaces
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018)
Most Hardy type inequalities concern boundedness of the Hardy type operators in Lebesgue spaces. In this paper we prove some new multi-dimensional Hardy type inequalities in Hölder spaces.