| 171. |
- Hrastinski, Stefan, et al.
(författare)
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Tutoring online tutors : Using digital badges to encourage the development of online tutoring skills
- 2018
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Ingår i: British Journal of Educational Technology. - : John Wiley & Sons. - 0007-1013 .- 1467-8535. ; 49:1, s. 127-136
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Tidskriftsartikel (refereegranskat)abstract
- Online tutors play a critical role in e-learning and need to have an appropriate set of skills in addition to subject matter expertise. This paper explores how digital badges can be used to encourage the development of online tutoring skills. Based on previous research, we defined three digital badges, which are examples of essential tutoring skills.These skills were self-assessed during two weeks by online tutors in K-12 mathematics, who also wrote a self-reflection based on their experience. The digital badges motivated tutors to reflect on online tutoring practices. The tutors described that they gained a more detailed understanding of the tutoring process when continuously analyzing ongoing conversations. However, it was a challenge for the tutors to balance the private activity, reflection on tutoring skills, and the social activity, communication with the K-12 students. It is essential to take into account when tutors will have time to reflect, for example, by scheduling time for reflection or enabling opportunities for reflection that is flexible in time. A challenge for further research is to better understand the potential benefits of different types of badges
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| 172. |
- Hummelgård, Christine, et al.
(författare)
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Physical and electrochemical properties of cobalt doped (Ti,Ru)O-2 electrode coatings
- 2013
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Ingår i: Materials Science & Engineering B: Solid-State Materials for Advanced Technology. - : Elsevier BV. - 0921-5107 .- 1873-4944. ; 178:20, s. 1515-1522
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Tidskriftsartikel (refereegranskat)abstract
- The physical and electrochemical properties of ternary oxides Ti0.7Ru0.3-xCoxO2 (x = 0.093 and x = 0) have been investigated and compared. Samples of three different thicknesses were prepared by spin-coating onto polished titanium to achieve uniform and well-defined coatings. The resulting electrodes were characterized with a variety of methods, including both physical and electrochemical methods. Doping with cobalt led to a larger number of micrometer-sized cracks in the coating, and coating grains half the size compared to the undoped samples (10 instead of 20 nm across). This is in agreement with a voltammetric charge twice as high, as estimated from cyclic voltammetry. There is no evidence of a Co3O4 spinel phase, suggesting that the cobalt is mainly incorporated in the overall rutile structure of the (Ti,Ru)O-2. The doped electrodes exhibited a higher activity for cathodic hydrogen evolution compared to the undoped electrodes, despite the fact that one third of the active ruthenium was substituted with cobalt. For anodic chlorine evolution, the activity was similar for both electrode types. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.
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| 173. |
- Hummelgård, Christine, et al.
(författare)
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Spin coated titanium-ruthenium oxide thin films
- 2013
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 536, s. 74-80
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Tidskriftsartikel (refereegranskat)abstract
- Substrates of different roughness spin coated with Ti0.7Ru0.3O2 films have been evaluated as model system for fundamental studies of the industrially and scientifically interesting (Ti, Ru)O-2 based electrodes. The approach allowed for much more accurate control over the material synthesis than the traditionally used brush-, dip-, or spray-coating, on titanium-metal substrates. It moreover yielded well-defined samples suitable for basic studies of the surface properties that are of fundamental importance for understanding the electrochemical functionality of the electrode. We have compared the films on silicon substrates to films prepared by spin coating the same material on titanium-metal substrates. Samples have been characterized using atomic force microscopy (AFM), X-ray diffraction, scanning electronmicroscopy (SEM), and cyclic voltammetry. The samples displayed a uniformity of the films appropriate for AFM characterization. The smoother the substrate the less cracks in the coating. Using easily broken silicon wafers as substrate, a straightforward sample preparation technique was demonstrated for cross-section SEM. In addition, using high spinning velocities we have deposited the oxide films directly on silicon-nitride grids, thin enough to allow for studies with transmission electron microscopy without further sample preparation.
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| 174. |
- Hyll, Kari, et al.
(författare)
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Flow imaging characterisation of morphological changes of chemical pulp due to refining
- 2016
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Ingår i: Nordic Pulp & Paper Research Journal. - : SPCI. - 0283-2631 .- 2000-0669. ; 31:3, s. 411-421
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Tidskriftsartikel (refereegranskat)abstract
- The influence of the refining process on the morphological changes of a chemical softwood pulp was investigated. The Voith LR40 industrial-like laboratory low consistency refiner was used, where the pulp was refined with five refining segments with differences in bar widths, groove widths, and cutting angles. The refined pulp was characterized with a fibre analyser with a spatial resolution of approximately 4 μm/pixel and a wide size range. The fines fraction of the refined pulp was also characterized with an imaging flow cytometer with a spatial resolution of 0.33 μm/pixel and a narrower size range. The fibre analyser measurements showed that the mean length, width, and aspect ratio of the fines decreased monotonically with accumulated refining energy. The imaging flow cytometer with its higher spatial resolution showed little change in fines morphology with accumulated refining energy. The morphology of the fines was more dependent on the applied specific refining energy than the design of the refining segment. However, a segment with much finer grooves and bars, initially designed for hardwood, gave significantly less fibre shortening, fines generation, external fibrillation, kink, and fines that were more fibrillar, compared to the other segments.Grant: The authors of this work would like to thank Prof. Lars Mattsson, Thomas Grahn, and Eva Ålander for fruitful discussions. The discussions with Lorentzen & Wettre were of great assistance. The financial support of the Swedish Energy Agency and the Önnesjöstiftelsen to the PhD project, and of the Fibre and Stock Design research programme to this evaluation study is gratefully acknowledged.
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| 175. |
- Högberg, Hans-Erik, et al.
(författare)
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Biocatalysis as a useful tool in pheromone synthesis. Enantiomerically pure building blocks from baker's yeast reductions and enzyme catalysed resoluti
- 1994
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Ingår i: Catalysis Today. - : Elsevier BV. - 0920-5861. ; 22:3, s. 591-606
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Tidskriftsartikel (refereegranskat)abstract
- Biocatalytical methods are presented which provide useful building blocks for pheromone synthesis. Examples of the utility of this approach are the preparation of building blocks for the synthesis of stereochemically pure isomers of pine sawfly pheromones and some other pheromones. Enantiom- erically pure ( 98% ee) 2-methyl-1-alkanols 2 were obtained via baker's yeast reduction of suitable α,β-unsaturated aldehydes, and by using lipases from Pseudomonas to effect resolution by transesterification of suitable racemic precursors to 2-methyl-1-alkanols 2 which gave high enantiomeric ratios E > 100. The resolution by esterification mediated by lipase from Candida rugosa of racemic 2-methylalkanoic acids also gave high enantiomeric ratios E> 100 after having improved the reaction conditions by regulating water activity, by choice of the appropriate complimentary substrate alcohol and by adjusting the initial equivalents of the latter present at the start. Also discussed is the separation of diastereomers of diprionol 1, which is naturally occurring in the pine sawfly Neodiprion sertifer, where it is the direct precursor of its pheromone.
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| 176. |
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| 177. |
- Högberg, Lovisa, 1983-
(författare)
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Building Sustainability : Studies on incentives in construction and management of real estate
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis summarizes the results from several studies with connection to sustainability in construction and management of real estate. Here, the concept sustainability includes environmental, social and economic dimensions and focus is on the actors with the best possibilities to impact real estate, namely the real estate owners and the developers. The thesis consists of six papers. Real estate owners’ perception of and incentives and strategies for sustainability was studied in four ways: incentives for energy efficiency and other sustainability issues in connection to renovation (papers I and II), factors that characterize firms with an ambitious approach to energy efficiency (paper V) and economic incentives for energy efficiency (paper VI). Developers’ behavior and impact on sustainability was studied in two ways: how developers’ planning and construction methods may influence energy consumption for future residents (paper III) and how developers relate to requirements for building environmental certification levels (paper IV).The first paper aims to clarify how housing firms see and treat energy efficiency matters in connection to renovation of multi-family buildings constructed during the 1960’s and 70’s. Interviews with housing firms resulted in four ideal housing firm types illustrating that housing firms have more or less incentives to improve energy efficiency. The second paper aimed to study a model for renovation of buildings in a residential area in peripheral Stockholm and to assess how it considers environmental, social and economic sustainability as well as technical concerns.Paper V builds on the results in paper I and aims to identify factors, on a firm level as well as in the surroundings of the firm, that characterize housing firms who own multi-family buildings from the 1960’s and 70’s and who have an ambitious approach to energy efficiency.Paper VI uses information from energy performance certificates to study whether better energy performance increases the selling price of single-family homes, which would increase owners’ incentives to improve energy efficiency.Paper III takes its starting point in an indicated shift in developers’ planning and construction practices for laundry facilities in owner-occupied multi-family buildings. The paper aims to clarify whether a shift has actually occurred from communal laundry rooms to in-unit laundry appliances and to illuminate the impact this could have on residents’ energy consumption for laundry. Paper IV reports the study of how developers who have adopted the environmental certification system LEED relate to the requirements for specific certification levels and how updated requirements risk undermining developers’ incentives for sustainable construction.
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| 178. |
- Högberg, Lovisa
(författare)
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Incentives for energy efficiency measures in post-war multi-family dwellings
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Energy efficiency is an important question to society as well as to individuals and firms. Improving energy efficiency in the building sector is considered an important means to climate mitigation. For real estate owners energy is also a central expenditure item and reducing energy consumption may directly reduce operation costs while at the same time serve as insurance against future energy price increases. Since new buildings only add a few percent annually to the building stock, the potential to reduce total energy consumption primarily lies within the existing building stock. The building stock is ageing and the post-war part of the stock that is in need of renovation is growing. This has been suggested as a window of opportunity to improve energy efficiency, but so far the results have been few. Several factors have been put forward to explain the so called energy efficiency gap – the difference between actual and optimal energy efficiency – one of which is split incentives. What adds to complexity in this case is that distinct differences have been observed in the level of ambition between the real estate companies that have renovated so far. Some companies have undertaken extensive renovation and energy efficiency measures, whereas other companies have done little more than urgent maintenance measures. It seems that real estate owners in general don´t have strong economic incentives to improve energy efficiency in connection to renovation – but what can then explain the differences between strategies? This licentiate thesis examines the incentives among real estate owners to improve energy efficiency, particularly in post-war, multi-family buildings in need of renovation. The purpose is to add knowledge about decisions concerning measures that improve energy efficiency - in terms of incentives, barriers and different motives for real estate owners’ strategies and actions. Results show that real estate owners lack strong economic incentives to invest in energy efficiency in multi-family buildings and the level of investment is dependent on the different motivations, grouped in three levels of ambition, that real estate companies have. One important conclusion is that the heterogeneity between companies that was exposed in the interviews and survey implies that they will not respond similarly to policy stimuli. The heterogeneity should thus be considered when designing policy measures so that public and company resources can be allocated as efficiently as possible, as there are many challenges facing owners of post-war residential buildings. Another conclusion is that from an economic point of view it is important to take the interaction between different measures into account, e.g. between physical measures and measures focusing on changing household behavior.
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| 179. |
- Högberg, Lovisa, et al.
(författare)
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Incentives for improving energy efficiency when renovating large-scale housing estates : A Case Study of the Swedish Million Homes Programme
- 2009
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 1:4, s. 1349-1365
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Tidskriftsartikel (refereegranskat)abstract
- Sweden has adopted ambitious energy savings objectives for buildings, but at the current rate of energy efficiency investments the objectives are unlikely to be reached. In this article we report the early findings of how real estate owners reason and act in energy efficiency investment decisions. Based on the results from interviews with the real estate companies, the companies have been divided into four ideal types that illuminate the differences in energy efficiency ambition and strategies; the Strict Profit Maximizing Company, the Little Extra Company, the Policy Led Ambitious Company and the Administration Led Ambitious Company. The different strategies will determine how the companies respond to incentives to invest in energy efficiency, and affect the overall result in the energy efficiency work. The ideal types hence are important to have in mind when designing policies to increase energy efficiency.
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| 180. |
- Högberg, Lovisa
(författare)
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Individual metering and charging in rental housing : creating the right incentives for energy saving?
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Changing user behavior by individually metering and charging tenants for their use of heating and hot water has been put forward as a means to reduce energy consumption in the building sector. This would give the tenant incentives to save energy, but at the same time weakens the landlord’s incentives for improving energy efficiency in the building, since she is no longer responsible for energy costs. These split incentives problems should be possible to avoid if there is a net gain from improving energy efficiency and/or installing individual metering that could be shared between the parties. The aim of this article is to problematize the concept of individual metering, to show through simulations that there are ways to avoid the split incentives problem involved, and to show that it should be possible to design contracts that give both landlord and tenant incentives to save energy. The results indicate that few energy efficiency investments will manage to bear their own investment costs, given how low the present value of the energy savings is at given energy prices. The results also show how split incentives may hinder the energy efficiency investments, but that there are conditions under which such investments and/or individual metering may increase welfare for landlord, tenant or both. Without negotiations this gain will not be reached, but through co-operation this welfare gain could be split which would benefit both landlord and tenant and this should be considered when designing contracts. Finally the findings highlight the importance to take into account the interaction of different means to save energy to avoid over-investment.
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