Evaluating Macroeconometric Modelling with Regard to Usefulness: a Survey

Macroeconometric models have during the last 40 years played an important role as a tool to guide decision making in public as well as private macroeconomic institutions. However, such models have not been much used in academic circles. We argue that macroeconometric models have problems both with regard to internal and external validity. Although the science of econometrics has partly answered the problem of internal validity, macroeconometric modelling is still dismissed by theorists as inappropriate for theoretical development. We find that the argument over how to evaluate macroeconometric modelling can be viewed as a result of the relationship between observed economic variables and economic theory.econometric models, theory of science

Solar activity and Svalbard temperatures

The long temperature series at Svalbard (Longyearbyen) show large variations, and a positive trend since its start in 1912. During this period solar activity has increased, as indicated by shorter solar cycles. The temperature at Svalbard is negatively correlated with the length of the solar cycle. The strongest negative correlation is found with lags 10-12 years. The relations between the length of a solar cycle and the mean temperature in the following cycle, is used to model Svalbard annual mean temperature, and seasonal temperature variations. Residuals from the annual and winter models show no autocorrelations on the 5 per cent level, which indicates that no additional parameters are needed to explain the temperature variations with 95 per cent significance. These models show that 60 per cent of the annual and winter temperature variations are explained by solar activity. For the spring, summer and fall temperatures autocorrelations in the residuals exists, and additional variables may contribute to the variations. These models can be applied as forecasting models. We predict an annual mean temperature decrease for Svalbard of 3.5\pm2 oC from solar cycle 23 to solar cycle 24 (2009-20) and a decrease in the winter temperature of \approx6 oC.Comment: 14 pages, including 5 figure

Informal Communication & its Relation to Employees, Managers, & Job Satisfaction

Color poster with text, images, graphs, and tables.Past research has shown that informal communication in the workplace is associated with job satisfaction (Nielson, Jex, & Adams, 2000). There are significant gaps in research regarding how managers perceive informal communication among employees in the workplace. Furthermore, little to no research has been conducted from an employee's point of view regarding informal communication and how it affects their job satisfaction. This study focuses on how employee's job satisfaction relates to their comfort communicating informally with co-workers and with managers, and if they perceive their managers to encourage friendships within the workplace.University of Wisconsin--Eau Claire Office of Research and Sponsored Programs

A Lithologic Report on the Coon Creek Tongue Ripley Formation, in Tennesse

In this report, a lithologic analysis of a sample of the Coon Creek tongue in southwestern Tennesse is given. The sediment is a olive gray siltstone, well sorted, with roundness values for the grains ranging from angular to subrounded. Quartz, biotite, and glauconite were the principal minerals observed. Porosity and permeability were variable, but mostly very good

Investigation and Development of Multiphysics Modeling Software Applications for Building Noise Control

COMSOL Multiphysics is a simulation software for modeling engineering processes and designs. The software can be used to create applications that allow users to change variables in a model and see the effect on the physics phenomenon under investigation. COMSOL applications can provide an interactive learning experience and help students visualize engineering concepts. This project examines the use of COMSOL to develop applications related to noise control in buildings, focusing on making them useful for education. Two applications were developed based on existing COMSOL models. One simulates sound absorption by a porous foam, and the other simulates sound propagation through a duct with a right-angled bend. The applications were used to calculate the absorption coefficient across frequency for a melamine foam sound absorber and the insertion loss across frequency for a duct. To test the applications’ accuracy, these results were compared with data from other software and from product data sheets. The results from the porous absorber application were reasonably accurate when compared to published data for a foam absorber. For the duct application, the calculated insertion loss values were close to the results from other software without an absorptive liner, although there was a larger discrepancy with a liner

On the Feasibility of Using Low-Melting Bath to Accommodate Inert Anodes in Aluminium Electrolysis Cells

Solheim, A. (2021). On the Feasibility of Using Low-Melting Bath to Accommodate Inert Anodes in Aluminium Electrolysis Cells. In: Perander, L. (eds) Light Metals 2021. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-65396-5_72Inert anodes for aluminium production can be made of ceramics, metals, or a mixture of those (cermets). Regardless of the type of anode, the surface will be an oxide. With high enough anode potential, the surface oxide will be decomposed upon formation of the corresponding fluoride, eventually leading to a catastrophic defect. The reversible voltage for decomposition was calculated for anode materials based on Ni, Fe, Cu, Co, and Cr in terms of the activities of alumina and aluminium fluoride at 960 °C and at 800 °C. Cu is the most promising candidate, when based on the decomposition voltage alone. It was found that the risk of failure was higher at low temperature, partly because low-melting baths have high activity of aluminium fluoride, and partly because it will be challenging to maintain high enough activity of alumina, even in a “slurry cell” where the bath consists of a suspension of tiny alumina particles. Based on a simplified model for the conditions inside the diffusion layer at the anode, it was estimated that the alumina particles in the slurry cannot be larger than 5–10 microns.acceptedVersio