Multi-threaded Output in CMS using ROOT

CMS has worked aggressively to make use of multi-core architectures, routinely running 4- to 8-core production jobs in 2017. The primary impediment to efficiently scaling beyond 8 cores has been our ROOT-based output module, which has been necessarily single threaded. In this paper we explore the changes made to the CMS framework and our ROOT output module to overcome the previous scaling limits, using two new ROOT features: the \texttt{TBufferMerger} asynchronous file merger, and Implicit Multi-Threading. We examine the architecture of the new parallel output module, the specific accommodations and modifications that were made to ensure compatibility with the CMS framework scheduler, and the performance characteristics of the new output module.Comment: Submitted to CHEP 2018 - 23rd International Conference on Computing in High Energy and Nuclear Physics; 6 pages, 4 figures, uses webofc clas

An approximate method for calculating three-dimensional inviscid hypersonic flow fields

An approximate solution technique was developed for 3-D inviscid, hypersonic flows. The method employs Maslen's explicit pressure equation in addition to the assumption of approximate stream surfaces in the shock layer. This approximation represents a simplification to Maslen's asymmetric method. The present method presents a tractable procedure for computing the inviscid flow over 3-D surfaces at angle of attack. The solution procedure involves iteratively changing the shock shape in the subsonic-transonic region until the correct body shape is obtained. Beyond this region, the shock surface is determined using a marching procedure. Results are presented for a spherically blunted cone, paraboloid, and elliptic cone at angle of attack. The calculated surface pressures are compared with experimental data and finite difference solutions of the Euler equations. Shock shapes and profiles of pressure are also examined. Comparisons indicate the method adequately predicts shock layer properties on blunt bodies in hypersonic flow. The speed of the calculations makes the procedure attractive for engineering design applications

Derivative claims and ratification: Time to ditch some baggage

The reform of the common law ‘derivative action’, by the statutory ‘derivative claim’ in Pt 11 of the Companies Act 2006, was long overdue. Many of the common law's most intractable problems, however, lay not with the derivative action itself, but rather with the law governing the ratification of breaches of duty. The source of many of these problems lay in the distinction the law sought to draw between fraudulent and non-fraudulent breaches, and the different consequences attached to each category of wrongdoing. The Companies Act 2006 was a timely opportunity at least to resolve the confusion within the law, and ideally to adopt what has been termed a ‘voting based’ approach to ratification. Sadly, the Act did neither, preferring instead to retain the common law largely untouched. Moreover, as a careful analysis of the Act itself shows, the modest changes it did introduce necessarily preserve the common law's distinction between fraud and non-fraud, and the uncertainty to which this gives rise. The paper concludes with an examination of Franbar Holdings v Patel, which illustrates clearly the shortcomings in the law's limited reforms

Achieving high catalytic activity and redox stability of doped ceria through a novel sol gel synthesis

Ceria is widely studied in catalysis because of its high oxygen mobility and storage capacity. These properties are enhanced by the incorporation of dopant atoms into the ceria crystal structure. However, creating a homogenously doped structure requires a suitable synthesis technique. Otherwise, dopant atoms form an oxide phase on the ceria surface, which blocks highly active catalytic sites. Traditional production methods allow for cerium and dopant ions to segregate during synthesis. In this work, we demonstrate a novel sol gel synthesis method for producing homogeneously doped ceria. The method is easy and avoids the use of hazardous chemicals. Higher dopant loadings and surface areas are achieved, which improves catalytic activity. Further, doped ceria is shown to be stable in both oxidizing and reducing environments, conditions under which traditional catalysts deactivate

A fluorescing spot on the temple: a helpful reminder for a detailed history and physical exam

We discuss a woman with a history of non-melanoma skin cancer who presented with a new erythematous macule on her right temple. On examination with Wood lamp the well-demarcated macule fluoresced pink making neoplasm unlikely. Further history and physical examination suggested an inadvertent ink stain and the patient was spared a biopsy highlighting the importance of eliciting a good history and performing a detailed physical examination with additional tools such as a Wood lamp when necessary

Pretreatment Of Cellulosic Biomass By Iron-Containing Magnetic Ionic Liquid Dissolution

The focus of this project is to determine the effectiveness in the preprocessing of biomass when magnetic ionic liquids (MIL) (1-butyl-3-methylimidazolium tetrachloroferrate (Bmim[FeCl4]) and 1-ethyl-3-methylimidazolium tetrachloroferrate (Emim[FeCl4])) are used as a green solvent. Lignocellulose is a promising starting material for a plethora of products, ranging from biofuels to custom chemicals; however, lignocellulose is resistant to enzymatic degradation. Various biomass-preprocessing techniques such as microbial, mechanical, and chemical pretreatment are used for enhancing the digestibility of biomass to sugars for ethanol production. Varieties of ionic liquids have demonstrated the ability to fragment lignocellulose. However, after fragmentation, separation of biomass and ionic liquids has proven to present economic challenges for this pretreatment process. Research has proven that the addition of magnetic properties to the ionic liquid can be used to stabilize the ionic liquids and prevent its loss or other detrimental fluid/fluid interactions in the bioreactor. Therefore, this paper presents the outcomes of such MIL dissolution studies

An Engineering Method for Interactive Inviscid-Boundary Layers in Three-Dimensional Hypersonic Flows

An engineering method has been developed that couples an approximate three dimensional inviscid technique with the axisymmetric analog and a set of approximate convective heating equations. The displacement effect on the boundary layer on the outer inviscid flow is calculated and included as a boundary condition in the inviscid technique. This accounts for the viscous interaction present at lower Reynolds numbers. The method is applied to blunted axisymmetric and three dimensional elliptic cones at angle of attack for the laminar hypersonic flow of a perfect gas. The method is applied to turbulent and equilibrium-air conditions. The present technique predicts surface heating rates, pressures, and shock shapes that compare favorably with experimental (ground-test and flight) data and numerical solutions of the Navier-Stokes and viscous shock-layer equations. In addition, the inclusion of viscous interaction significantly improves results obtained at lower Reynolds numbers. The new technique represents a major improvement over current engineering aerothermal methods with only a modest increase in computational effort