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This paper reviews literature on the rationale, challenges, and recommendations for choosing a nonequivalent comparison (NEC) group design when evaluating intervention effects. After reviewing frequently addressed threats to validity, the paper describes recommendations for strengthening the research design and how the recommendations were implemented in a current study. Next, tests were performed in order to investigate whether the added design components had contributed to increased internal validity by creating comparable cluster groups at baseline. In order to estimate the external validity or the potential generalizability of results, the statistical power of the study was calculated up front and representativeness of the participating schools in relation to other schools in Norway was examined. Baseline comparisons indicated that the addition of several design elements, such as the random invitation of multiple, stratified, and active comparison groups, may have reduced significant validity threats stemming from selection bias. The need for more accurate and reliable effect estimates in school-based evaluation research is discussed.

While it is generally assumed that the aim of teacher evaluation is to "formatively" support teachers' professional development, research finds that teacher evaluation practices are predominantly "summative". This paper describes a Norwegian governmental policy experiment aiming to overcome this fallacy through a bargaining process, where experience-based knowledge was combined with research evidence. When preparing to introduce teacher evaluation, the Ministry of Education and Research commissioned a group of researchers and a group representing practitioners to identify teacher evaluation practices that are conducive for educational quality. Drawing on experiences from the policy experiment, the article discusses three approaches to teacher evaluation: the political, the administrative and the professional. The analysis indicates that successful implementation of interventions needs a new educational infrastructure and professional school leadership. One conclusion is that teacher evaluation cannot be successfully implemented through traditional linear approaches. A more productive approach is to treat it as a wicked problem.

The decomposition of water by electricity, and the voltaic pile as a means of generating electricity, have both held an iconic status in the history of science as well as in the history of science teaching. These experiments featured in chemistry and physics textbooks, as well as in classroom teaching, throughout the nineteenth and twentieth centuries. This paper deals with our experiences in restaging the decomposition of water as part of a history of science course at the Norwegian University of Science and Technology, Trondheim, Norway. For the experiment we used an apparatus from our historical teaching collection and built a replica of a voltaic pile. We also traced the uses and meanings of decomposition of water within science and science teaching in schools and higher education in local institutions. Building the pile, and carrying out the experiments, held a few surprises that we did not anticipate through our study of written sources. The exercise gave us valuable insight into the nature of the devices and the experiment, and our students appreciated an experience of a different kind in a history of science course. (Contains 2 figures and 8 footnotes.)

Abstract: The paper describes results of experimental investigations of confined granular flow in a silo with different inserts. Over 100 experiments were carried out with dry cohesionless sand in a large metal silo with and without inserts at Tel-Tek, dept. POSTEC, in Norway. Wall pressures and flow patterns were measured during both silo filling and emptying. Three different insert types were used in the silo: double cone, cone-in-cone and inverted cone. Different positions of inserts were also investigated. Experimental results with inserts were compared with those without inserts. Some design recommendations for silos equipped with inserts were worked out. [Copyright &y& Elsevier]

Abstract: This paper compares the ignitability of Troll B crude oil weathered under simulated Arctic conditions (0%, 50% and 90% ice cover). The experiments were performed in different scales at SINTEF’s laboratories in Trondheim, field research station on Svalbard and in broken ice (70–90% ice cover) in the Barents Sea. Samples from the weathering experiments were tested for ignitability using the same laboratory burning cell. The measured ignitability from the experiments in these different scales showed a good agreement for samples with similar weathering. The ice conditions clearly affected the weathering process, and 70% ice or more reduces the weathering and allows a longer time window for in situ burning. The results from the Barents Sea revealed that weathering and ignitability can vary within an oil slick. This field use of the burning cell demonstrated that it can be used as an operational tool to monitor the ignitability of oil spills. [Copyright &y& Elsevier]

Sending text messages reminding people to vote has only been examined as a mobilization tool in three studies, two of them done in the United States. The results from these studies are mixed. We investigate this tool's effectiveness using a field experiment in a different context, municipal elections in Norway. We find strong mobilization effects among groups traditionally low in participation (immigrants and youth voters). Young native Norwegians show an intent-to-treat (ITT) effect of 4.58% points, foreign nationals who have recently established Norwegian residency show an ITT effect of 2.93% points, and among immigrants who have lived in Norway for 7 years or more the treatment effect is 2.7% points. Even among native Norwegian voters over 30, with a baseline turnout of 73%, text messages generate a 0.96% points increase in turnout. [ABSTRACT FROM AUTHOR]

A reliable simulation model to calculate the motion and force responses of wave energy converters (WECs) is imperative to ensure the reliability and long-term performance of WEC systems; these aspects are fundamental to achieving full commercialisation of wave energy. A simulation model was developed and validated concerning the simulated WEC buoy motions in a previous study; this study validated the mooring force calculations for the same model. The example WEC system comprises a buoy, a power take-off (PTO) system, and a three-leg mooring system wherein each leg is divided into two taut segments joined by a submerged float. A 1:20 physical model was built and tested in the Deepwater Offshore Basin at Shanghai Jiao Tong University. Numerical models were developed to simulate the coupled hydrodynamic and structural responses of the WEC system, primarily using potential flow theory, the boundary element method, the finite element method, and the Morison equation. The simulated and measured axial force results at the top ends of the six mooring segments were compared; the results agreed best in the lower segments of each mooring leg and in the moorings on the downwind side because of the PTO system uncertainties and the uncalibrated damping in the numerical model. Nonetheless, the numerical model reasonably predicted the moorings' accumulated fatigue damage, demonstrating that the model can be reliably used for mooring structural analyses. The study also used the validated numerical model to simulate a full-scale WEC system installed in Runde, Norway. A comparison of the results from the full-scale measurements and simulations shows that the numerical simulation model exhibited a good predictive capability for the mooring forces of the full-scale WEC system. [ABSTRACT FROM AUTHOR]

Although field experiments have documented the contemporary relevance of discrimination in employment, theories developed to explain the dynamics of differential treatment cannot account for differences across organizational and institutional contexts. In this article, I address this shortcoming by presenting the main empirical findings from a multi-method research project, in which a field experiment of ethnic discrimination in the Norwegian labour market was complemented with forty-two in-depth interviews with employers who were observed in the first stage of the study. While the experimental data support earlier findings in documenting that ethnic discrimination indeed takes place, the qualitative material suggests that theorizing in the field experiment literature have been too concerned with individual and intra-psychic explanations. Discriminatory outcomes in employment processes seems to be more dependent on contextual factors such as the number of applications received, whether requirements are specified, and the degree to which recruitment procedures are formalized. I argue that different contexts of employment provide different opportunity structures for discrimination, a finding with important theoretical and methodological implications. [ABSTRACT FROM AUTHOR]

Observations of high spatio-temporal resolution from a precipitation network across Stord Island, located off the west coast of southern Norway, are compared to state-of-the-art numerical model simulations. The 12 week long observation period shows a clear orographic precipitation signal across the 10-15 km wide island (peak elevation 750 m). The model experiment designed to capture this signal is run with 9-3-1 km nested grid and results are compared with observations at different accumulation intervals. The total amount of precipitation over the 12 week period is underpredicted, even for the 1 km grid. The maximum precipitation intensity, however, is slightly overpredicted. Time-step (5 s) precipitation from the model is also compared with observed intensities at the highest possible temporal resolution permitted by the rain collection method. The observations indicate that most of the precipitation is formed at intensities from 5 to 20 mm h−1. A smaller fraction of the precipitation is formed with intensities >20 mm h−1. The simulated precipitation at the 3 km grid did not reproduce at the correct intensities. The 1 km grid showed an improved tendency to produce the precipitation at the right intensities, but had too high maximum intensities. A test simulation where the intermediate grid had no cumulus parametrization was performed. Even though effects such as undercatchment and unresolved terrain influenced, it was concluded that the test run performed better than the control run. The investigation concluded that, in general, a 1 km grid is sufficient for capturing the most intensive precipitation event in a satisfying way. [ABSTRACT FROM AUTHOR]

In this article, the authors explore how the extrinsic cues corporate social responsibility, endorsement, and country of origin affect consumer evaluations of product quality, value, and expected product popularity for frozen Pangasius filets, a farmed fish product just recently introduced into the Norwegian market. The effects of these three variables are tested on purchase intentions. By means of a 2 × 2 × 2 factorial experiment in combination with survey data, the authors find that the three extrinsic cues under study had different effects on the evaluative variables. Furthermore, these variables all had positive and significant effects on purchase intentions. Hence, the general conclusion is that importers of new food products like Pangasius can benefit from focusing on extrinsic cues when the intrinsic cues are hard to evaluate or are unknown. Through the indirect effect on purchase intentions, extrinsic cues play an important role when consumers judge unfamiliar and new products. [ABSTRACT FROM AUTHOR]

The Proterozoic (950 Ma) Lyngdal granodiorite of southern Norway belongs to a series of hornblende–biotite metaluminous ferroan granitoids (HBG suite) coeval with the post-collisional Rogaland Anorthosite–Mangerite–Charnockite (AMC) suite. This granitoid massif shares many geochemical characteristics with rapakivi granitoids, yet granodiorites dominate over granites. To constrain both crystallization (P, T, fO2, H2O in melt) and magma generation conditions, we performed crystallization experiments on two samples of the Lyngdal granodiorite (with 60 and 65 wt % SiO2) at 4–2 kbar, mainly at fO2 of NNO (nickel–nickel oxide) to NNO + 1, and under fluid-saturated conditions with various H2O–CO2 ratios for each temperature. Comparison between experimental phase equilibria and the mineral assemblage in the Lyngdal granodiorite indicates that it crystallized between 4 and 2 kbar, from a magma with 5–6 wt % H2O at an fO2 of NNO to NNO + 1. These oxidized and wet conditions sharply contrast with the dry and reduced conditions inferred for the petrogenesis of the AMC suite and many other rapakivi granites worldwide. The high liquidus temperature and H2O content of the Lyngdal granodiorite imply that it is not a primary magma produced by the partial melting of the crust but is derived by the fractionation of a mafic magma. Lyngdal-type magmas appear to have volcanic equivalents in the geological record. In particular, our results show that oxidized high-silica rhyolites, such as the Bishop Tuff, could be derived via fractionation of oxidized intermediate magmas and do not necessarily represent primary crustal melts. This study underlines the great variability of crystallization conditions (from anhydrous to hydrous and reduced to oxidized) and petrogenetic processes among the metaluminous ferroan magmas of intermediate compositions (granodiorites, quartz mangerites, quartz latites), suggesting that there is not a single model to explain these rocks. [ABSTRACT FROM PUBLISHER]

The friction loss in a part of the rock-blasted unlined tunnel of the Litjfossen hydropower plant in Norway was determined from experimental and numerical studies. Remote sensing data from the prototype tunnel provided the input data for both the numerical model and the construction of a 1:15 scale model with an innovative milling approach. The numerical simulations were based on the solution of the Reynolds-averaged Navier–Stokes equations using the CFD program OpenFoam. Head loss measurements in the scale model were carried out by means of pressure measurements for a range of discharges and were compared against the results of the numerical model. The measured data were used to determine the Darcy–Weisbach and Manning friction factors of the investigated tunnel reach. The high-resolution remote sensing data were also used to test the applicability of existing approaches to determine the friction factor in unlined rock blasted tunnels. The results of the study show the usefulness of the chosen hybrid approach of experimental investigations and numerical simulations and that existing approaches for the determination of head losses in unlined tunnels need to be further refined. [ABSTRACT FROM AUTHOR]