Reformulation of the Hermitean 1-Matrix Model as an Effective Field Theory

The formal Hermitean 1-matrix model is shown to be equivalent to an effective field theory. The correlation functions and the free energy of the matrix model correspond directly to the correlation functions and the free energy of the effective field theory. The loop equation of the field theory coupling constants is stated. Despite its length, this loop equation is simpler than the loop equations in the matrix model formalism itself since it does not contain operator inversions in any sense, but consists instead only of derivative operators and simple projection operators. Therefore the solution of the loop equation could be given for an arbitrary number of cuts up to the fifth order in the topological expansion explicitly. Two different methods of obtaining the contributions to the free energy of the higher orders are given, one depending on an operator H and one not depending on it

CLSVOF as a fast and mass-conserving extension of the level-set method for the simulation of two-phase flow problems

The modeling of two-phase flows in computational fluid dynamics is still an area of active research. One popular method is the coupling of level-set and volume-of-fluid (CLSVOF), which benefits from the advantages of both approaches and results in improved mass conservation while retaining the straightforward computation of the curvature and the surface normal. Despite its popularity, details on the involved complex computational algorithms are hard to find and if found, they are mostly fragmented and inaccurate. In contrast, this article can be used as a comprehensive guide for an implementation of CLSVOF into the existing level-set Navier–Stokes solvers on Cartesian grids in three dimensions

Numerical Simulation of Droplets with Dynamic Contact Angles

The numerical simulation of droplet impact is of interest for a vast variety of industrialprocesses, where practical experiments are costly and time-consuming. In these simulations, the dynamic contact angle is a key parameter, but the modeling of its behavior is poorly understood so far. One of the few models, which considers the overall physical context of the involved 'moving contact line problem' is Shikhmurzaev’s interface formation model. In addition to keeping the problem well-posed, all surface and bulk parameters, such as the contact angle, are determined as part of the solution rather than being prescribed functions of contact line speed. In this thesis, we couple an asymptotic version of the interface formation model with our three-dimensional incompressible two-phase Navier-Stokes solver NaSt3DGPF developed at the Institute for Numerical Simulation, Bonn University. With this sophisticated model, the droplet shapes, heights and diameters compare very well with those from a range of practical experiments

How Systems Analysts Can Provide More Effective Assistance to the Policy Maker

Policy makers do not benefit from advances in (a) systems analysis or (b) judgement and decision theory because neither of these disciplines recognize the incompleteness of its methodology. A complete methodology requires a synthesis of the two. This RM explains why such a synthesis is necessary, describes how it can be achieved, and provides a worked-out example of its application to the problem of changing sources of energy production in the US. The example also illustrates that the linkage of systems analysis and judgement theory provides information that neither discipline can provide separately. Finally, the RM shows that such information is policy relevant and that it provides more effective assistance to the policy maker than does either approach used separately

North Sea Oil: Resource Requirements for Development of the U.K. Sector

From the first exploration wells in 1964 to virtual self-sufficiency by 1980, the development of the U.K. North Sea oil fields has been rapid and productive. However, the hostile environment and the sheer scale of the operation have made heavy demands on both natural and human resources. Just how large has this investment of resources been? Has it been justified by the amount of energy recovered? What lessons does the development of the North Sea hold for operators of other offshore fields? Using an approach developed at IIASA, the author attempts to answer these questions. He presents a wealth of detailed information obtained from exhaustive literature searches and close cooperation with the North Sea oil companies themselves, and uses it to investigate the resources needed to construct and operate the various field installations and facilities. From this starting point he then derives the total amounts of resources required to develop each field and then the entire U.K. sector. To put this resource expenditure in perspective, the author describes the way in which estimates of North Sea oil reserves have evolved and examines the additional yields that may be obtained by using technologically advanced oil-recovery methods; also included is an interesting comparison of the "energy economics" of producing either gas or oil from the North Sea. Finally, there are extensive descriptions of the U.K. oil fields currently in production or at advanced stages of development, giving details of reserves, production rates, and ownership, together with full information on the production platforms, storage facilities, and pipelines employed in each field

Software Engineering Basics Part 1: Introduction & Distributed Version Control

Einführung in Git und Gitlab mit Live-Coding

Influence of host genetics on the severity of coccidioidomycosis.

Coccidioidomycosis, a mild flulike illness in approximately 40% of infected persons, progresses to severe pulmonary or disseminated disease in 1% to 10% of symptomatic cases. We examined host genetic influences on disease severity among class II HLA loci and the ABO blood group. Participants included African-American, Caucasian, and Hispanic persons with mild or severe disseminated coccidioidomycosis from Kern County, California. Among Hispanics, predisposition to symptomatic disease and severe disseminated disease is associated with blood types A and B, respectively. The HLA class II DRB1*1301 allele marks a pre-disposition to severe disseminated disease in each of the three groups. Reduced risk for severe disease is associated with DRB1*0301-DQB1*0201 among Caucasians and Hispanics and with DRB1*1501-DQB1*0602 among African-Americans. These data support the hypothesis that host genes, in particular HLA class II and the ABO blood group, influence susceptibility to severe coccidioidomycosis