Seasonal variations in Greenland Ice Sheet motion : Inland extent and behaviour at higher elevations

Peer reviewedPreprin

Adaptive Comparative Judgment for Polytechnic Transformation: Assessment across the Curriculum

The authors are investigating potential applications of adaptive comparative judgment (ACJ) across numerous environments and learning scenarios within the Purdue Polytechnic Institute as part of Purdue’s efforts to transform the undergraduate learning experience. Six courses or program areas were selectedfor the study, involving a wide variation in subjects, subject matter, and assessment artifacts. The authors anticipate that positive results from these pilot studies will encourage broader and deeper applications of ACJ in the Purdue Polytechnic, across Purdue University, and in other academic institutions. Results from these scenarios will be disseminated in future conferences and scholarly journals

The 2DECOMP&FFT library: an update with new CPU/GPU capabilities

The 2DECOMP&FFT library is a software framework written in modern Fortran to build large-scale parallel applications. It is designed for applications using three-dimensional structured meshes with a particular focus on spatially implicit numerical algorithms. However, the library can be easily used with other discretisation schemes based on a structured layout and where pencil decomposition can apply. It is based on a general-purpose 2D pencil decomposition for data distribution and data Input Output (I/O). A 1D slab decomposition is also available as a special case of the 2D pencil decomposition. The library includes a highly scalable and efficient interface to perform three-dimensional Fast Fourier Transforms (FFTs). The library has been designed to be user-friendly, with a clean application programming interface hiding most communication details from application developers, and portable with support for modern CPUs and NVIDIA GPUs (support for AMD and Intel GPUs to follow)

Small Mammal Abundances in a Grassland and Forest Area at the Lake Fayetteville Environmental Center, Arkansas

We examined changes in abundance of small mammals in forest and prairie-grassland habitat at Lake Fayetteville, Arkansas over a period of 32 years. We estimated the population size of small mammals using a mark-recapture method by capturing small mammals employing rat-sized Sherman live traps laid out in a grid with 8 rows of traps, 15 traps per row, 9.14 m (30 feet) between traps and rows covering an area of 1.01 ha (2.5 acres) in size. Six species of mammals were trapped in the prairie-grassland and three species were captured in the forest habitat. In the forest, the white-footed deermouse (Peromuscus leucopus)was greatest in 1998 and in 2006. In the prairie-grassland, the population of hispid cotton rats (Sigmodon hispidus) were greatest in 2004, 2008, 2010 and 2014 and have increased over the years with the change in grass composition. The prairie-grassland in 1962 was mainly a broomsedge bluestem (Andropogon virginicus) field but as time progressed more and more prairie grasses invaded helped by controlled burns and removal of the invading eastern red cedars (Juniperus virginiana). The population of Sigmodon hispidus was weakly correlated with the minimum winter temperatures from the previous year

Xcompact3D: An open-source framework for solving turbulence problems on a Cartesian mesh

Xcompact3D is a Fortran 90–95 open-source framework designed for fast and accurate simulations of turbulent flows, targeting CPU-based supercomputers. It is an evolution of the flow solver Incompact3D which was initially designed in France in the mid-90’s for serial processors to solve the incompressible Navier–Stokes equations. Incompact3D was then ported to parallel High Performance Computing (HPC) systems in the early 2010’s. Very recently the capabilities of Incompact3D have been extended so that it can now tackle more flow regimes (from incompressible flows to compressible flows at low Mach numbers), resulting in the design of a new user-friendly framework called Xcompact3D. The present manuscript presents an overview of Xcompact3D with a particular focus on its functionalities, its ready-to-run simulations and a few case studies to demonstrate its impact

Di-neutron correlation and soft dipole excitation in medium mass neutron-rich nuclei near drip-line

The neutron pairing correlation and the soft dipole excitation in medium-mass nuclei near drip-line are investigated from a viewpoint of the di-neutron correlation. Numerical analyses by means of the coordinate-space HFB and the continuum QRPA methods are performed for even-even $^{18-24}$O, $^{50-58}$Ca and $^{80-86}$Ni. A clear signature of the di-neutron correlation is found in the HFB ground state; two neutrons are correlated at short relative distances \lesim 2 fm with large probability $\sim 50$. The soft dipole excitation is influenced strongly by the neutron pairing correlation, and it accompanies a large transition density for pair motion of neutrons. This behavior originates from a coherent superposition of two-quasiparticle configurations $[l\times (l+1)]_{L=1}$ consisting of continuum states with high orbital angular momenta $l$ reaching an order of $l\sim 10$. It raises a picture that the soft dipole excitation under the influence of neutron pairing is characterized by motion of di-neutron in the nuclear exterior against the remaining $A-2$ subsystem. Sensitivity to the density dependence of effective pair force is discussed.Comment: 35 pages, 22 figure

Critical Behavior of the Meissner Transition in the Lattice London Superconductor

We carry out Monte Carlo simulations of the three dimensional (3D) lattice London superconductor in zero applied magnetic field, making a detailed finite size scaling analysis of the Meissner transition. We find that the magnetic penetration length \lambda, and the correlation length \xi, scale as \lambda ~ \xi ~ |t|^{-\nu}, with \nu = 0.66 \pm 0.03, consistent with ordinary 3D XY universality, \nu_XY ~ 2/3. Our results confirm the anomalous scaling dimension of magnetic field correlations at T_c.Comment: 4 pages, 5 ps figure

Evolution of level density step structures from 56,57-Fe to 96,97-Mo

Level densities have been extracted from primary gamma spectra for 56,57-Fe and 96,97-Mo nuclei using (3-He,alpha gamma) and (3-He,3-He') reactions on 57-Fe and 97-Mo targets. The level density curves reveal step structures above the pairing gap due to the breaking of nucleon Cooper pairs. The location of the step structures in energy and their shapes arise from the interplay between single-particle energies and seniority-conserving and seniority-non-conserving interactions.Comment: 9 pages, including 5 figure

Doodles on surfaces

Doodles were introduced in but were restricted to embedded circles in the 2-sphere. Khovanov, extended the idea to immersed circles in the 2-sphere. In this paper we further extend the range of doodles to any closed oriented surfaces. Uniqueness of minimal representatives is proved, and various example of doodles are given with their minimal representatives. We also introduce the notion of virtual doodles, and show that there is a natural one-to-one correspondence between doodles on surfaces and virtual doodles on the plane