Advice seeking network structures and the learning organization

Organizational learning can be described as a transfer of individuals’ cognitive mental models to shared mental models. Employees, seeking the same colleagues for advice, are structurally equivalent, and the aim of the paper is to study if the concept can act as a conduit for organizational learning. It is argued that the mimicking of colleagues’ advice seeking structures will induce structural equivalence and transfer the accuracy of individuals’ cognitive mental models to shared mental models. Taking a dyadic level of analysis authors revisit a classical case and present novel data analyses.The empirical results indicate that the mimicking of advice seeking structures can alter cognitive accuracy. It is discussed the findings’ implications for organization learning theory and practice, addressed the study’s limitations, and suggested avenues for future research

Sliding Contact Dynamic Force Spectroscopy Method for Interrogating Slowly Forming Polymer Cross-Links

Dynamic Single Molecule Force Spectroscopy (SMFS), conducted most commonly using AFM, has become a widespread and valuable tool for understanding the kinetics and thermodynamics of fundamental molecular processes such as ligand-receptor interactions and protein unfolding. Where slowly forming bonds are responsible for the primary characteristics of a material, as is the case in crosslinks in some polymer gels, care must be taken to ensure that a fully equilibrated bond has first formed before its rupture can be interpreted. Here we introduce a method, sliding contact force spectroscopy (SCFS), which effectively eliminates the kinetics of bond formation from the measurement of bond rupture. In addition it permits bond rupture measurements in systems where one of the binding partners may be introduced into solution prior to binding without tethering to a surface. Taking as an exemplar of a slowly forming bond the ‘eggbox’ junction crosslinks between oligoguluronic acid chains (oligoGs) in the commercially important polysaccharide alginate, we show that SCFS measures accurately the equilibrated bond strength of the crosslink when one chain is introduced into the sample solution without tethering to a surface. The results validate the SCFS technique for performing single molecule force spectroscopy experiments, and show that it has advantages in cases where the bond to be studied forms slowly and where tethering of one of the binding partners is impractical

Were the 2022 Summer Heatwaves a Strong Cause of Europe’s Excess Deaths?

During the 2022 summer, Europe experienced heatwaves with record temperatures, and a study has argued that they caused about 62,000 deaths between 30 May and 4 September. The total number of excess deaths during the same period was about 137,000, indicating that the heatwaves were a substantial contributor. Not ruling out that explanation entirely, this paper argues that it was unlikely a strong cause. First, if the heatwaves were a strong cause of numerous deaths, one would assume that the older and deprived were relatively likely to die. However, during the 2022 summer heatwaves in England, which were claimed to have caused about 2900 deaths, the oldest age cohort did not have a higher excess death rate than the middle age cohort, and the excess death rate actually decreased with deprivation status. Moreover, Iceland had among Europe’s highest excess death rates during the summer, which cannot be attributed to heatwaves. During June, July, and August 2022, comparable southern hemisphere countries furthermore had high excess death rates, which cannot be attributed to heatwaves either, as it was during their winter. Also, Europe’s excess death rate was higher during the 2022–2023 winter than during the 2022 summer, and intuitively not attributed to heatwaves, but neither to cold weather, as that winter was abnormally mild. Finally, the paper discusses the puzzling issue that about 56% more women than men, relative to the population, presumably died from the heatwaves.publishedVersio

Protective films on molten magnesium

Molten magnesium will oxidize uncontrollably in an atmosphere of air. To inhibit this, a protective gas is used to cover the melt. The gas most commonly used today is SF6. Fluorine is known to be the active component of the gas. There is a major problem with SF6, and that is that it has a strong Global Warming Potential (GWP). The GWP of SF6 is 23 900 times that of CO2. The aim of the present work is to understand the mechanism of the protection of molten magnesium. Hopefully, this allows us to find less problematic alternatives to the use of SF6 gas. The present work was performed with three different experimental units: - A furnace was especially built to expose molten magnesium to various atmospheres. - A hot stage made it possible to study the surface of the molten or solid sample under the microscope at high temperature with SF6 or with other gases in the atmosphere. - Finally, the solubility of fluorine in magnesium was measured at temperatures from 700°C to 950°C. To obtain a basic knowledge of magnesium melt protection, molten magnesium was exposed to various combinations of gases. Both SF6 and SO2 in air protects molten magnesium well from oxidation. It is also known that pure CO2 has a protective effect. In these experiments, it was tested whether SF6 and SO2 in other carrier gases than air will be protective. Nitrogen, argon and CO2 were used as carrier gases. Also, air was added to CO2 to see how much air the CO2 can contain and still be protective. An important conclusion for SF6 and SO2 is that air is necessary to build a protective film on the melt surface. Inert gases like nitrogen and argon will obviously not oxidize the metal, but since no film forms on the melt, the metal will keep on evaporating. A CO2 atmosphere can contain at least 20% air, and still be protective. Problems employing CO2, are that the metal surface gets discolored, which is at least a cosmetic problem, and that C may be introduced into the metal, which may give corrosion problems. The hot stage placed under an optical microscope made it possible to observe the magnesium sample as it was heated under an atmosphere of SF6 in air, pure CO2 and 1% SO2 in air. The samples were held at temperatures from 635°C to 705°C for varying holding times. The partial pressure of SF6 was varied between 0.5 and 5%. The samples produced were excellent for further studies with Transmission Electron Microscope (TEM), Field Emission Scanning Electron Microscope (FESEM), microprobe and Focused Ion Beam Milling (FIB). The examinations showed that a thin, dense film was formed. Magnesium fluoride particles formed on the interface between the metal and the oxide film in some cases. It is suggested that then the magnesium oxide is saturated with fluorine. The fluorine diffuses through the oxide layer and forms magnesium fluoride at the interface between MgO and Mg. In other cases, it is seen that a matrix rich in fluorine forms in between larger oxide grains. Combinations of these two situations are also seen. Proposed explanations for the protective behavior of SF6 are: -the formation of a second phase, that is magnesium fluoride, which helps to give a Pilling-Bedworth ratio close to one. -the formation of a MgO matrix containing F. The thickness of the films formed with SF6 is found to be proportional to the square root of time. The proportionality constant depends on temperature and the partial pressure of SF6 in the gas. Samples in CO2 heated above the melting point did not keep their initial shape. The films formed with CO2 are probably therefore not as strong as the films formed in SF6 since these samples managed to keep their initial shape even after they had melted. The surfaces after exposure to CO2 were black and uneven. Formation of MgCO3 has not been confirmed in this work. Also thermodynamic calculations indicated that MgCO3 does not form. It was not possible to tell experimentally whether the sulphur found in the samples exposed to SO2 is bound as magnesium sulphide or magnesium sulphate or even dissolved in MgO, although it may look like two different phases are present with a slightly different sulphur content. Thermodynamic calculations do not indicate that MgSO4 should form. It was considered to introduce fluorine directly into the melt as an alternative to the use of SF6. In this case formation of MgF2 would limit the content of fluorine in the molten magnesium. Therefore, the solubility of fluorine in molten magnesium has been studied by melting magnesium in a magnesium fluoride crucible. Samples were taken at various temperatures from 700°C up to 950°C. Three different analytical methods were employed to measure the fluorine content: The Sintalyzer method, Glow Discharge Mass Spectrometry (GD-MS) and Secondary Ion Mass Spectrometry (SIMS). The various analytical methods did not all give the same results. However, it is suggested that the SIMS results are the most reliable. The value for the dissolution of fluorine, 1/2 F2 (g) =F (in mass%) is then: ΔG°3/2 = (- 329 000 + 65 000) - (83+64)T ΔGo for the equilibrium between magnesium and magnesium fluoride, MgF2 = Mg (l) + 2F is found to be: ΔGo = (471 000 ± 131 000) - (350±130) T Iron is found to have no effect on the solubility of fluorine in molten magnesium. The solubility of fluorine does not seem to be sufficiently high for direct dissolution of fluorine into the melt to be an alternative to SF6. Iron is found to have no effect on the solubility of fluorine in molten magnesium. The solubility of fluorine does not seem to be sufficiently high for direct dissolution of fluorine into the melt to be an alternative to SF6

Long-term hydrothermal Scheduling with aggregate and individual Reservoirs

This thesis is a comparative analysis of two commensurable models used in long-term hydrothermal scheduling. The first model is the EMPS model, which is the most prevalent tool for long-term planning in the Norwegian power industry. The second model is known as the SOVN model, which is currently under development at SINTEF Energy Research. A tighter market coupling to the continental European power system with an increasing penetration of intermittent and non-storable renewable energy, requires models that better represent the flexibility of the Nordic hydropower system, since the reservoir aggregation of the EMPS model has proven inadequate to fully handle this. SOVN aims to circumvent this through a detailed simulation of the hydropower system, where the production at each individual power plant is optimized through a complex SLP algorithm using Benders decomposition. Moreover, the SOVN model does not require the same substantial user input as EMPS, which can help minimizing some of the uncertainty of the results. The first part of this thesis covers the Nordic hydropower system, power system economics and the general framework for long-term hydrothermal scheduling. In the two subsequent chapters the EMPS and SOVN models are thoroughly introduced, both conceptually and mathematically. The analytical part of this thesis is initiated with a review of the case scenarios and power system data: The analysis addresses a confined power system in Northern Norway, where adjacent markets are represented as exogenous price files. The first part of the analysis examines the influence on the performance of SOVN by changing the settings in the SOVN.ctrl file. The remaining analysis investigates the power system in extreme surplus situations, by introducing increased wind power development in the region, given as discrete scenarios between 265 and 4,835 MW installed capacity. In the most moderate of these cases, the share of unregulated production, i.e. production with zero opportunity cost, in EMPS and SOVN is 28.71% and 7.81%, respectively. With 4,835 MW installed wind energy these shares are increased to 44.06% and 9.28%. That is, not only does SOVN minimize its forced production, it also reduces the impact of surplus situations on its operational liberty. Consequently, spillage in SOVN is also significantly reduced: The total percentage of spillage to optional production in the three southernmost subareas, is more than 6% in EMPS and approximately 1% in SOVN. Power surplus results in lower wholesale prices for both models, and bottlenecks in the grid evoke price gaps between adjacent market. In the most extreme case, SOVN reduces the mean price gap with 3.04 EURO/MWh relative to EMPS and maintains a more uniform price structure across all markets. The occurrence of extremely low prices is reduced significantly. There is still room for improvement regarding the socioeconomic performance of SOVN, whose results were slightly weaker than those in EMPS. Moreover, the pumping pattern of the SOVN model seems somewhat arbitrary and contradicts basic market logic, partly due to the significant drop in prices in time steps where the pumps are being used, relative to cases with no pumps. Overall, the results from SOVN show consistently improved ability to allocate production such as to maintain a high level of operational flexibility. The heuristic drawdown allocation of the EMPS model seems less capable of providing the individual plants with the correct market signals, which results in higher levels of spillage and forced production. Comparing the output of individual plants in the two models generally shows that the less regulated plants, i.e. plants with only a few months storage capacity, increase their output in SOVN. These plants are generally the most prone to spillage and forced production, and it seems that these properties are incorporated in their respective water values. Likewise, plants with greater storage capacity and capability show higher tendency to withhold their water, which follows from increased water values. The more uniform price structure across all coupled markets is also an indication of the SOVN model s ability to utilize the transfer capacity more efficiently. The results show a higher utilization of the transfer capacity away from surplus areas, which indicates an improved market handling

(Dis)Embodied Cognition: Phenomenology, Spirit(ual)ism, and Performance in Proust

A psychical researcher among Marcel Proust’s contemporaries called belief in the paranormal “the Dreyfus case of science.” References to spirit-life abound in Proust’s fiction, but critics have resisted readings that attend seriously to the numerous references in À la recherche du temps perdu to reincarnation, spirit-possession, and, especially, mediumship. The paper reads them through the lens of long-standing critical controversies, particularly concerning the relationship of Proust’s aesthetics and ontology with those of Henri Bergson and Maurice Merleau-Ponty. The paper accepts Nathalie Aubert’s finding in her 2011 essay “Proust et Bergson: La mémoire du corps” that Proust’s insistence on embodiment validates the reluctance of critics since Georges Poulet to connect him with Bergson and makes him, in a sense, a phenomenologist avant la lettre. The paper argues, however, that for Proust a phenomenological interpretation neglects some varieties of experience, and it investigates ways metaphors, particularly in the context of musical performance, drawn from spiritualism inflect his phenomenology and address its limitations

Review of Here Lies Hugh Glass: A Mountain Man, a Bear, and the Rise of the American Nation\u3c/i\u3e By Jon T. Coleman

Jon T. Coleman’s Here Lies Hugh Glass attempts to apply flesh to the corporeal body of Hugh Glass through the use of nineteenth-century hyperbole and twentieth-century reinvention. As such, Coleman weaves narratives of fiction and fact together, giving the reader a disjointed summation of Glass’s life, a life Coleman suggests is more Homer Simpson than Homer’s Odysseus. We see a character emerge in 1823 who is wounded in a battle with the Arikaras and survives a mauling by a female grizzly bear, only to meet his end ten years later at the hands of Arikaras along the banks of the Yellowstone River. Beginning in 1825 with James Hall, the first person to write of Hugh Glass’s ordeal, Coleman reveals a series of chroniclers less interested in the man than the scars he carried

Alginate sequencing: Block distribution in alginates and its impact on macroscopic properties

PhD i bioteknologiPhD in Biotechnolog

VIV Fatigue Investigation for Subsea Planar Rigid Spools and Jumpers

Master's thesis in Offshore Technology: Marine and Subsea TechnologyToday, most new field developments consist of a subsea production system. Rigid spools and jumpers are important parts of these systems as they accommodate pipeline expansion and contraction due to changes in pressure and temperature, or due to movements of structural members. As rigid spools and jumpers are located near the sea bottom and normally consist of significant free spans, they could be subjected to seabed currents. These seabed currents, if large enough, can lead to vortex induced vibrations (VIV), which will lead to fast accumulation of fatigue damage. As failure of a rigid spool or jumper will have severe environmental and economic consequences, a proper fatigue assessment should be done to ensure sufficient fatigue life and avoid fatigue failure. The complex geometry of rigid spools and jumpers means that the flow field and hence the vortex shedding will be complex. Currently, there are no proven design guideline or software available for assessing VIV response of a rigid spool/jumper. Moreover, the available design guidelines or software do not normally account for the torsional stiffness of the structure. Hence, they do not consider the fatigue damage due to torsional stresses. The objective of this study is to benchmark the prediction of the global response of a "M" shaped rigid jumper and investigate methods to account for torsional stress in fatigue analysis. A validation study has been performed to evaluate the use of the semi-empirical program, i.e. VIVANA, and a response model approach based on DNV-RP-F105 (2006) to predict the VIV response of rigid spools and jumpers. These two VIV prediction approaches have been used to predict the VIV response of an “M” shaped rigid jumper exposed to varying current speeds hitting the jumper plane at two different angles. The two prediction methods have been evaluated against the existing experimental data. When the current hits the jumper plane at a 10° angle, VIVANA seems to give fairly good predictions on the response frequency/mode and maximum displacement amplitude for most current speeds. The response model approach, on the other hand, seems to give large overpredictions of the displacement amplitude for most current speeds at this current direction. When the current has a 90° angle relative to the jumper plane, both VIVANA and the response model approach give good predictions with respect to the maximum jumper response. iii The results from the validation study are further used to calculate the fatigue damage of the rigid jumper. A methodology presented in Nair et al. (2011) is used to calculate the torsional stresses. This methodology is based on using the stress assessment method and the fatigue assessment method given in DNV-RP-F105 (2006), which originally is for stresses due to bending (i.e. flexural stresses), to also calculate the stresses due to torsion. Then the fatigue damage is calculated using two different methods. In method 1, the fatigue damage due to flexural stress ranges and the fatigue damage due torsional stress ranges are calculated separately. In method 2, the first principal stress range is used to calculated the fatigue damage. For all current speeds and both current directions, method 2 gives higher fatigue damage for current velocities where the torsional stress contribution is large. Method 2 is also somewhat less time-consuming than method 1