Implementation of 2D Domain Decomposition in the UCAN Gyrokinetic Particle-in-Cell Code and Resulting Performance of UCAN2

The massively parallel, nonlinear, three-dimensional (3D), toroidal, electrostatic, gyrokinetic, particle-in-cell (PIC), Cartesian geometry UCAN code, with particle ions and adiabatic electrons, has been successfully exercised to identify non-diffusive transport characteristics in present day tokamak discharges. The limitation in applying UCAN to larger scale discharges is the 1D domain decomposition in the toroidal (or z-) direction for massively parallel implementation using MPI which has restricted the calculations to a few hundred ion Larmor radii or gyroradii per plasma minor radius. To exceed these sizes, we have implemented 2D domain decomposition in UCAN with the addition of the y-direction to the processor mix. This has been facilitated by use of relevant components in the P2LIB library of field and particle management routines developed for UCLA's UPIC Framework of conventional PIC codes. The gyro-averaging specific to gyrokinetic codes is simplified by the use of replicated arrays for efficient charge accumulation and force deposition. The 2D domain-decomposed UCAN2 code reproduces the original 1D domain nonlinear results within round-off. Benchmarks of UCAN2 on the Cray XC30 Edison at NERSC demonstrate ideal scaling when problem size is increased along with processor number up to the largest power of 2 available, namely 131,072 processors. These particle weak scaling benchmarks also indicate that the 1 nanosecond per particle per time step and 1 TFlops barriers are easily broken by UCAN2 with 1 billion particles or more and 2000 or more processors.This work was supported in part in the USA by Grant No. DE-FG02-04ER54741 to the University of Alaska, Fairbanks, AK, from the Office of Fusion Energy Sciences, Office of Science, United States Department of Energy. It was also supported in part at Universidad Carlos III, Madrid, Spain, by Spanish National Project No. ENE2009-12213-C03-03. This research used resources of the National Energy Research Scientific Computing Center (NERSC), which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. It also took advantage of resources at the Barcelona Supercomputing Center (BSC), Centro Nacional de Supercomputación, Barcelona, Spain. One of us (Leboeuf) would particularly like to thank David Vicente from BSC and Zhengji Zhao from NERSC for their help in the porting, debugging, and optimization of UCAN2 on the mainframes at their respective centers

The Design and Evaluation of Computer Music Interfaces

The purpose of this research is to examine the methods employed to design a computer music system suitable for music composition purposes. The nature of an interface is introduced and discussed (Chapter 2), with particular reference to interfacing issues for computer music users. The nature of the user and the notion of a task in computer music are discussed and examined (Chapter 3), with outline methods for evaluations of users and tasks being introduced. Current computer systems design and analysis methodologies are introduced (Chapter 4), and subsequently adapted for use in computer music design and analysis applications. A set of guidelines is introduced in Chapter 5, specifically related to the design and analysis of computer music systems. These guidelines are formulated from the discussions regarding the interfacing requirements of a musician user and the nature of the tasks he wishes to accomplish employing computer related technology. An examination of several systems forms a major part of the thesis (Chapters 6 - 10), outlining a variety of available composition tools at the time of writing. Each system introduced and discussed is evaluated in relation to the guidelines introduced for design and analysis of computer music systems. An interface design case study (Chapter 11) employs the design methods introduced during the thesis, and highlights the need for intensive designer - user discourse

Fraud, Abuse, and Opioids

This Article analyzes recent government enforcement actions involving two health care fraud and abuse authorities, including the federal Anti- Kickback Statute and the federal civil False Claims Act, in cases involving opioids. Part II of this Article examines recent government enforcement actions involving the federal Anti-Kickback Statute, which prohibits (among other conduct) the exchange of remuneration for opioid prescriptions, patient referrals for drug testing services, and patient referrals for addiction treatment services if such prescriptions or services are reimbursed in whole or in part by a federal health care program. Part III of this Article examines recent government enforcement actions involving the federal civil False Claims Act, which prohibits (among other conduct) factually and legally false opioid prescription claims, drug testing claims, and addiction treatment claims when such claims are submitted for payment to a federal health care program. Finally, Part IV addresses the role of the Anti-Kickback Statute and the False Claims Act in combating the opioid crisis and highlights new government initiatives in this area, including: (1) the Prescription Interdiction & Litigation Task Force, created by the Department of Justice in February 2018; (2) the Eliminating Kickbacks in Recovery Act, signed into law by President Trump in October 2018; and (3) a mega anti-fraud program known as the Unified Program Integrity Contractor, announced by the Centers for Medicare and Medicaid Services in November 2018

Inventory of ammonia emissions from UK agriculture 2009

The National Ammonia Reduction Strategy Evaluation System (NARSES) model (spreadsheet version) was used to estimate ammonia (NH3) emissions from UK agriculture for the year 2009. Year-specific livestock numbers and fertiliser N use were added for 2009 and revised for previous years. The estimate for 2009 was 231.8 kt NH3, representing a 2.3 kt increase from the previously submitted estimate for 2008. Backward and forward projections using the 2009 model structure gave estimates of 317, 245 and 244 kt NH3 for the years 1990, 2010 and 2020, respectively. This inventory reports emission from livestock agriculture and from nitrogen fertilisers applied to agricultural land. There are a number of other minor sources reported as ‘agriculture’ in the total UK emission inventory, including horses not kept on agricultural holdings, emissions from composting and domestic fertiliser use