Bayesian signaling

This paper introduces private sender information into a sender-receiver game of Bayesian persuasion with monotonic sender preferences. I derive properties of increasing differences related to the precision of signals and use these to fully characterize the set of equilibria robust to the intuitive criterion. In particular, all such equilibria are either separating, i.e., the sender's choice of signal reveals his private information to the receiver, or fully disclosing, i.e., the outcome of the sender's chosen signal fully reveals the payoff-relevant state to the receiver. Incentive compatibility requires the high sender type to use sub-optimal signals and therefore generates a cost for the high sender type in comparison to a full information benchmark in which the receiver knows the sender's type. The receiver prefers the equilibrium outcome over this benchmark for large classes of monotonic sender preferences

Imitation in Heterogeneous Populations

We study a boundedly rational model of imitation when payoff distributions of actions differ across types of individuals. Individuals observe others’ actions and payoffs, and a comparison signal. One of two inefficiencies always arises: (i) uniform adoption, i.e., all individuals choose the action that is optimal for one type but sub-optimal for the other, or (ii) dual incomplete learning, i.e., only a fraction of each type chooses its optimal action. Which one occurs depends on the composition of the population and how critical the choice is for different types of individuals. In an application, we show that a monopolist serving a population of boundedly rational consumers cannot fully extract the surplus of high-valuation consumers, but can sell to consumers who do not value the good

Microchannel zeolite 13X adsorbent with high CO2 separation performance

Abstract Uniform 13X films with thicknesses of 3 and 11 µm were grown on supports in the form of steel monoliths with a cell density of 1600 cpsi and microchannels width of 0.5 mm. Sharp breakthrough fronts and a dynamic uptake of 3.4 mmol CO2 g−1 zeolite were observed in the forwarding step of breakthrough experiments for a feed of 10% CO2 in N2 with a high flow rate at 293 K and 1 bar. Numerical modeling showed that the adsorption process was very fast and that the transport of CO2 in the thin zeolite layer was the rate-limiting step, the mass transfer resistance for the 11 µm film is 2.2 times lower than zeolite 13X pellets and 100 times lower than zeolite 4A beads. Axial dispersion, pressure drop, and gas film resistance were shown to be negligible. The steel monolith support provides good mechanical strength and excellent thermal conductivity for the 13X films. The combination of properties makes this adsorbent a good performer when compared with other types of structured zeolite adsorbents in reported literatures. This microchannel adsorbent is a promising alternative to traditional adsorbents in processes of fast CO2 separation with short cycle times

Pervaporation of Ethanol/Water Mixtures Through a High-Silica MFI Membrane: Comparison of Different Semi-Empirical Mass Transfer Models

Pervaporation of binary ethanol/water solutions of 5–10 wt.% ethanol was studied experimentally through a thin supported high-silica MFI zeolite membrane of hydrophobic character in the temperature range of 30–70 °C. The fluxes obtained were very high, 2–14 kg m-2h-1 with ethanol/water separation factors of 4–7. The loss of effective driving force was significant in the supporting layers, which limited the membrane performance. The correlation between the experimental data and three different semi-empirical mass-transfer models was examined. The correlation was good especially when the driving force for mass-transfer was determined based solely on bulk feed, or the bulk feed and permeate conditions together. Somewhat lower correlation was observed when the driving force was corrected with the effect of support resistance. This was most likely due to the inaccuracies of the used mass transfer parameters in the support. The investigated semi-empirical models can be applied for initial stage process design purposes

Adsorption of butanol and water vapors in silicalite-1 films with a low defect density

Pure silica zeolites are potentially hydrophobic and have therefore been considered to be interesting candidates for separating alcohols, e.g., 1-butanol, from water. Zeolites are traditionally synthesized at high pH, leading to the formation of intracrystalline defects in the form of silanol defects in the framework. These silanol groups introduce polar adsorption sites into the framework, potentially reducing the adsorption selectivity toward alcohols in alcohol/water mixtures. In contrast, zeolites prepared at neutral pH using the fluoride route contain significantly fewer defects. Such crystals should show a much higher butanol/water selectivity than crystals prepared in traditional hydroxide (OH–) media. Moreover, silanol groups are present at the external surface of the zeolite crystals; therefore, minimizing the external surface of the studied adsorbent is important. In this work, we determine adsorption isotherms of 1-butanol and water in silicalite-1 films prepared in a fluoride (F–) medium using in situ attenuated total reflectance–Fourier transform infrared (ATR–FTIR) spectroscopy. This film was composed of well intergrown, plate-shaped b-oriented crystals, resulting in a low external area. Single-component adsorption isotherms of 1-butanol and water were determined in the temperature range of 35–80 °C. The 1-butanol isotherms were typical for an adsorbate showing a high affinity for a microporous material and a large increase in the amount adsorbed at low partial pressures of 1-butanol. The Langmuir–Freundlich model was successfully fitted to the 1-butanol isotherms, and the heat of adsorption was determined. Water showed a very low affinity for the adsorbent, and the amounts adsorbed were very similar to previous reports for large silicalite-1 crystals prepared in a fluoride medium. The sample also adsorbed much less water than did a reference silicalite-1(OH–) film containing a high density of internal defects.The results show that silicalite-1 films prepared in a F– medium with a low density of defects and external area are very promising for the selective recovery of 1-butanol from aqueous solutions

Microstructure of Bentonite in Iron Ore Green Pellets

Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compac

Impacts of climate change on global food trade networks

Countries’ reliance on global food trade networks implies that regionally different climate change impacts on crop yields will be transmitted across borders. This redistribution constitutes a significant challenge for climate adaptation planning and may affect how countries engage in cooperative action. This paper investigates the long-term (2070-2099) potential impacts of climate change on global food trade networks of three key crops: wheat, rice and maize. We propose a simple network model to project how climate change impacts on crop yields may be translated into changes in trade. Combining trade and climate impact data, our analysis proceeds in three steps. First, we use network community detection to analyse how the concentration of global production in present-day trade communities may become disrupted with climate change impacts. Second, we study how countries may change their network position following climate change impacts. Third, we study the total climate-induced change in production plus import within trade communities. Results indicate that the stability of food trade network structures compared to today differs between crops, and that countries’ maize trade is least stable under climate change impacts. Results also project that threats to global food security may depend on production change in a few major global producers, and whether trade communities can balance production and import loss in some vulnerable countries. Overall, our model contributes a baseline analysis of cross-border climate impacts on food trade networks

Resipientovervåking av utslipp fra Elstrøm renseanlegg, Skien, i 2022

Prosjektleder: Camilla H. Corneliussen HagmanPå oppdrag fra Skien kommune har NIVA laget et overvåkingsprogram for å møte kravene i utslippstillatelsen til Elstrøm renseanlegg som har neddykket utslipp til Farelva. Overvåkingen startet i 2022 og omfattet undersøkelser ved to referansestasjoner oppstrøms utslippet, to antatt påvirkede stasjoner samt en stasjon nedstrøms i større avstand til utslippet. Det ble undersøkt for begroing (heterotroft og alger), bunndyr, metaller i sedimenter og kjemisk vannkvalitet, i tillegg til planteplankton i den oppdemmede innsjøen Hjellevannet. Undersøkelsene viste ingen betydelige forskjeller mellom referansestasjonene og øvrige stasjoner, og god eller svært god tilstand for alle parametere bortsett fra bunndyr. Uegnede fysiske forhold for bunndyr ved de fleste stasjonene gjør at det ikke kan konkluderes med at dårlig tilstand for bunndyr er knyttet til påvirkning fra utslippet, men kan like gjerne være pga. mangel på egnet habitat. Det er derfor ingen ting i denne undersøkelsen som tyder på at Farelva, Hjellevannet eller Skienselva er påvirket i stor grad av utslippet til Elstrøm renseanlegg.Skien kommunepublishedVersio

Undersøkelse av innsjøresipienter fra Larvikittbruddene, fase 1 - 2022

Prosjektleder: Camilla H. Corneliussen HagmanTo innsjøer nedstrøms Larvikitt-bruddet i Tvedalen, Larvik kommune, ble i 2022 undersøkt for effekter av påvirkning fra steinbruddet på vannkvalitet, sedimenter, vannplanter og bunndyr. Undersøkelsen ble utført som en oppfølging av tidligere undersøkelser i 2007 og 2008. Resultatene tyder på at vannkvaliteten i innsjøene ikke er eutrofierte, og at turbiditeten er betydelig bedret, men at forholdene fremdeles tilsier signifikant partikkelpåvirkning i form av reduserte lysforhold for vannplanter, spesielt i Bålsrødvannet. I Torpevannet ble det funnet svært lite vannplanter uten opplagt årsak til dette, derfor kunne ikke effekter fra steinbruddet vurderes. Bunndyrundersøkelsene ga ingen opplagte svar på omfanget av evt. påvirkning fra steinbruddet. Resultatene fra 2022 tyder totalt sett på at Bålsrødvannet er mest, og fremdeles, preget av partikkelforurensning fra Tvedalen steinbrudd, men at forholdene er betydelig bedret siden 2007 og 2008.WSP Norge ASpublishedVersio

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe