Gas Storage Valuation: Price Modelling v. Optimization Methods

The existence of a financial gas market motivates the analysis of gas storage as a separate asset, using the market value context for utilization and valuation. In the recent literature, gas storage is typically analysed within a framework with a simple one-factor price dynamics that is solved to optimality. We follow a different approach, where the market is represented by a forward curve with daily granularity, the price uncertainty is represented by six factors, and where we impose a simple and intuitive storage strategy that follows from repeated maximization of the intrinsic value. Based on UK natural gas market price data, we obtain the gas storage value using our approach, and compare with results from one-factor models as well as with perfect foresight. We find that our approach captures much more of the true flexibility value than the one-factor models. Our results indicate that the appropriate framework for analyzing complex assets like gas storage is a rich representation of the price dynamics combined with a simple and intuitive decision rule.Energy; uncertainty; flexibility; exercise strategy

The Social Robot: A Study of the Social and Political Aspects of Automatic Milking Systems

We explored social and political aspects of milking robot (automatic milking system; AMS) use and expansion in dairy farming. Over 30 % of dairy farms in Norway have an AMS, and the percentage is rapidly increasing. We interviewed 26 dairy farmers with AMSs in the county of Rogaland, Norway. Primary motives for investing in milking robots are a more flexible workday, reduced physical work, and a desire to join the perceived future standard of dairy farming. Although farmers are motivated by social factors, AMS is a key element in a structural change driven by political, economic, and social factors

Social integration mechanisms to strengthen absorptive capacity in agricultural advisory service organisations

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Cloning of the β-phycocyanin gene from Anacystis nidulans

AbstractThe β-phycocyanin gene, pcyB, of Anacystis nidulans was isolated from an Escherichia coli λ-phage bank by the use of synthetic oligonucleotides derived from the 170 amino acid sequence of the β-phycocyanin protein. Two positive, overlapping λ-clones were found. Partial DNA sequencing of one of the clones gave a deduced amino acid sequence which was in full agreement with a portion of the published sequence of A. nidulans β-phycocyanin. A comparison with the published DNA sequence for β-phycocyanin from Agmenellum quadruplicatum shows a DNA sequence homology of 70.4% over the sequenced region

Comparison of the SF6D, the EQ5D, and the oswestry disability index in patients with chronic low back pain and degenerative disc disease

Background The need for cost effectiveness analyses in randomized controlled trials that compare treatment options is increasing. The selection of the optimal utility measure is important, and a central question is whether the two most commonly used indexes - the EuroQuol 5D (EQ5D) and the Short Form 6D (SF6D) – can be used interchangeably. The aim of the present study was to compare change scores of the EQ5D and SF6D utility indexes in terms of some important measurement properties. The psychometric properties of the two utility indexes were compared to a disease-specific instrument, the Oswestry Disability Index (ODI), in the setting of a randomized controlled trial for degenerative disc disease. Methods In a randomized controlled multicentre trial, 172 patients who had experienced low back pain for an average of 6 years were randomized to either treatment with an intensive back rehabilitation program or surgery to insert disc prostheses. Patients filled out the ODI, EQ5D, and SF-36 at baseline and two-year follow up. The utility indexes was compared with respect to measurement error, structural validity, criterion validity, responsiveness, and interpretability according to the COSMIN taxonomy. Results At follow up, 113 patients had change score values for all three instruments. The SF6D had better similarity with the disease-specific instrument (ODI) regarding sensitivity, specificity, and responsiveness. Measurement error was lower for the SF6D (0.056) compared to the EQ5D (0.155). The minimal important change score value was 0.031 for SF6D and 0.173 for EQ5D. The minimal detectable change score value at a 95% confidence level were 0.157 for SF6D and 0.429 for EQ5D, and the difference in mean change score values (SD) between them was 0.23 (0.29) and so exceeded the clinical significant change score value for both instruments. Analysis of psychometric properties indicated that the indexes are unidimensional when considered separately, but that they do not exactly measure the same underlying construct. Conclusions This study indicates that the difference in important measurement properties between EQ5D and SF6D is too large to consider them interchangeable. Since the similarity with the “gold standard” (the disease-specific instrument) was quite different, this could indicate that the choice of index should be determined by the diagnosis

Tiltak for å redusere sykefravær: Eiendom & Intern Service - Askim kommune

I denne rapporten ser vi nærmere på årsakene til at den kommunale virksomheten Eiendom & Intern Service i Askim kommune har fått en positiv utvikling i sykefraværet. Undersøkelsen viser at virksomheten har klart å kombinere organisasjonsutvikling, med ivaretakelse av den enkelte ansatte. Det har i virksomheten etter hvert utviklet seg en vilje til å tilrettelegge arbeidsplassen slik at de som trenger det får tilpassete arbeidsoppgaver. Den organisasjonsutviklingen som er gjennomført har medført at virksomheten har fått større muligheter til slik tilpasning og den muligheten har virksomheten utnyttet. Det er viktig å understreke at aksepten for individuell tilrettelegging finnes både hos ledelse og hos kollegaer. I rapporten konkluderer vi derfor med at både struktur, ledelse og sosialt miljø har utviklet seg slik at særskilt tilrettelegging er blitt akseptert. Dette har skapt muligheter for å ivareta ansatte med særlige behov – en mulighet virksomheten har utnyttet

Arbeid som recovery-strategi

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Phosphorus desorption and isotope exchange kinetics in agricultural soils

To improve phosphorus (P) fertilization and environmental assessments, a better understanding of release kinetics of solid-phase P to soil solution is needed. In this study, Fe (hydr)oxide-coated filter papers (Fh papers), isotopic exchange kinetics (IEK) and chemical extractions were used to assess the sizes of fast and slowly desorbing P pools in the soils of six long-term Swedish field experiments. The P desorption data from the Fh-paper extraction of soil (20 days of continual P removal) were fitted with the Lookman two-compartment desorption model, which estimates the pools of fast (Q(1)) and slowly (Q(2)) desorbing P, and their desorption rates k(1) and k(2). The amounts of isotope-exchangeable P (E) were calculated (E-1min to E->3 months) and compared with Q(1) and Q(2). The strongest relationship was found between E-1 min and Q(1) (r(2) = .87, p < .01). There was also an inverse relationship between the IEK parameter n (the rate of exchange) and k(1) (r(2) = .52, p < .01) and k(2) (r(2) = .52, p < .01), suggesting that a soil with a high value of n desorbs less P per time unit. The relationships between these results show that they deliver similar information, but both methods are hard to implement in routine analysis. However, Olsen-extractable P was similar in magnitude to Q(1) (P-Olsen = 1.1 x Q(1) + 2.3, r(2) = .96), n and k(1) were related to P-Olsen/P-CaCl2, while k(2) was related to P-oxalate/P-Olsen. Therefore, these extractions can be used to estimate the sizes and desorption rates of the different P pools, which could be important for assessments of plant availability and leaching