Glaciers melt as mountains warm: a graphical case study

For the 2006 ASA Data Exposition we created graphics that, in the legacy of John Tukey, tried to “force the unexpected upon us” (Tukey in Proceedings of the 18th conference on design of experiments in Army research and development I, Washington, 1972). The data were geographic and meteorological measurements taken every month for 6 years on a coarse 24 by 24 grid covering Central America. Using conventional static graphics and some less conventional interactive graphics, we were able to find expected features in the data, such as seasonal patterns, spatial correlations, and El Niño events, as well as some more surprising results, several of which were corroborated by stories in the news.     

Irradiation-induced segregation and diffusion of manganese implants in nickel

The effects of radiation-induced solute redistribution and diffusion are studied for 30 keV Mn implants in nickel irradiated with 75 keV Ni⁺ ions at 500°C. The peak of the Mn implant profile is driven to greater depth with increasing irradiation dose until a steady-state solute profile is established. The rate of drift of Mn atoms and their diffusion coefficient is related to the distribution of point-defects in the nickel under irradiation.     

The first pulsar discovered by FAST

<正>To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and processing pipelines. We tested and used three pipelines, two (P1 and P2 hereafter) searched for the periodic signature of pulsars     

VideoAFM--a new tool for high speed surface analysis

The VideoAFM provides a 1000 fold increase in image rate compared to conventional atomic force microscopes, giving nanometre resolution images of surfaces at a rate of 15 frames s(-1), which is approximately 1 million pixels s(-1). Images of high stiffness surfaces such as calibration grids are provided for the first time, and allow for a more rigorous examination of the meaning of the data obtained with the VideoAFM. Instrumental changes that could provide true topographic images are discussed. The advantages of a high speed scanning technique that is integrated within a conventional AFM are outlined. Particular emphasis is given to the capability to 'tile' images, and hence rapidly map large areas with nanometre resolution. It is found that the inherent increase in stability that comes from a high frame rate leads to the possibility of manually manipulating the sample while maintaining a sharp image, allowing real-time user interaction with the AFM. The possible application of the VideoAFM approach for the very rapid analysis of surface properties and, ultimately, surface chemistry is discussed and some possible routes are given.     

Effects of Mineral Dissolution Ratios on Chemical-Dissolution Front Instability in Fluid-Saturated Porous Media

The main purpose of this article is to investigate, both theoretically and computationally, the effects of mineral dissolution ratios on the different respects of chemical-dissolution front instability problems in fluid-saturated porous media. In order to get a better understanding of how the mineral dissolution ratio affects the propagation and evolution of a planar chemical-dissolution front in an infinite space consisting of a fluid-saturated porous medium, the theoretical analysis method is used to derive the generous solution to the propagation speed of the planar chemical-dissolution front, while the computational simulation method is employed to simulate the detailed evolution process when the planar chemical-dissolution front is evolved into complicated morphologies at the supercritical Zhao numbers. The related theoretical results reveal that the mineral dissolution ratio plays an important role in controlling the propagation speed of a planar chemical-dissolution front in the fluid-saturated porous medium. An increase in the value of the mineral dissolution ratio can result in a remarkable decrease in the value of the propagation speed of a planar chemical-dissolution front. On the other hand, the related computational simulation results demonstrate that the mineral dissolution ratio has a considerable influence on the evolution pattern of a planar chemical-dissolution front during its propagation in the fluid-saturated porous medium. An increase in the mineral dissolution ratio can reduce the likelihood for a planar chemical-dissolution front to evolve from the initial planar shape into different morphologies within the fluid-saturated porous medium of finite size.     

A nonlinear bilevel model for analysis of electric utility demand-side planning issues

An application of bilevel programming in the electric utility industry is presented. The model is nonlinear and is used to analyze various economic issues that affect electric utility planning. The electric utility at the upper level of the model seeks to minimize costs or maximize benefits while controlling electric rates and subsidizing energy conservation programs. Customers at the lower level attempt to maximize their net benefit by consuming electricity and investing in conservation. This model considers factors such as free riders and the rebound effect which affect the net benefits of utility resource plans but are ignored by most planning models. The model's solutions shed light on utility issues including whether there can be a practical difference between various objectives, including minimizing cost (least cost planning) and maximizing net social welfare (value based planning).