Physical Sciences and Mathematics Commons^™

The Arctic Research Of The Composition Of The Troposphere From Aircraft And Satellites (Arctas) Mission: Design, Execution, And First Results, D J. Jacob, J H. Crawford, H Maring, A D. Clarke, J E. Dibb, L K. Emmons, R A. Ferrare, C A. Hostetler, P B. Russell, H B. Singh, A M. Thompson, G E. Shaw, E Mccauley, J R. Pederson, J A. Fisher

Jenny A Fisher

The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission was conducted in two 3-week deployments based in Alaska (April 2008) and western Canada (June–July 2008). Its goal was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1) influx of mid-latitude pollution, (2) boreal forest fires, (3) aerosol radiative forcing, and (4) chemical processes. The June–July deployment was preceded by one week of flights over California (ARCTAS-CARB) focused on (1) improving state emission inventories for greenhouse gases and aerosols, (2) providing observations to test and improve models …

Composition And Optical Properties Of Secondary Organic Aerosol Particles, Felisha Imholt, Ryan Caylor, Matthew E. Wise, John Shilling

Matthew E. Wise

No abstract provided.

Composition Of Secondary Organic Aerosols, Ryan Caylor, Felisha Imholt, Matthew E. Wise, John Shilling

Matthew E. Wise

Determination Of The Optical Properties Of Secondary Organic Aerosol Particles, Matthew E. Wise

Matthew E. Wise

The enhanced greenhouse effect is currently considered to be our most important global environmental problem. While the magnitude of radiation absorbed by greenhouse gases is known to a high certainty, the absorption of radiation by atmospheric aerosol particles is not. In the initial Visiting Faculty Program application, we proposed the use of an ultraviolet-visible (UV/Vis) spectrometer equipped with a liquid waveguide capillary flow cell to determine the extent to which secondary organic aerosol particles (SOA) absorb visible light. Early in the research period, the UV/Vis technique was optimized for three solvent systems (methanol, water and 0.1 M hydrochloric acid). Using …

Average Mass Scan Of The Total Ion Chromatogram Versus Percentage Chemical Composition In Multivariate Statistical Comparison Of Complex Volatile Mixtures, Niko Radulovic, Polina Blagojevic, Danielle Skropeta

Danielle Skropeta

The analysis of complex volatile mixtures by gas chromatography-mass spectrometry (GC-MS) is a time-consuming process. It involves separation and identification of the components based on their retention times and fragmentation patterns, followed by determination of their relative percentages from integration of their peak areas. Herein we show that multivariate statistical analysis of the relative abundances of the m/z values obtained from the average mass scans (AMS) of the complex mixture is a faster and potentially more reliable method of assessing these mixtures. To achieve this, 15 model complex mixtures, were prepared comprising varying amounts of 10 different constituents. The AMS …

An Overview Of Observations Of Unstable Layers During The Turbulent Oxygen Mixing Experiment (Tomex), J. H. Hecht, Alan Z. Liu, R. L. Bishop, J. H. Clemmons, C. S. Gardner, M. F. Larsen, R. G. Roble, G. R. Swenson, R. L. Walterscheid

Alan Z Liu

The Turbulent Oxygen Mixing Experiment (TOMEX) was designed to measure the atmospheric response to the existence of unstable layers as determined by wind and temperature measurements from 80 to 105 km. TOMEX combined Na lidar measurements, from Starfire Optical Range in Albuquerque, New Mexico, with a launch of a payload from White Sands Missile Range, located between 100 and 150 km south of Starfire. The payload included a trimethyl aluminum chemical release to measure winds and diffusion, a 5-channel ionization gauge to measure neutral density fluctuations at high vertical resolution, and a 3-channel photometer experiment to measure atomic oxygen related …

Bryophyte Species Composition Over Moisture Gradients In The Windmill Islands, East Antarctica: Development Of A Baseline For Monitoring Climate Change Impacts, J Wasley, S A. Robinson, J D. Turnbull, D H. King, W Wanek, M Popp

Sharon Robinson

Extreme environmental conditions prevail on the Antarctic continent and limit plant diversity to cryptogamic communities, dominated by bryophytes and lichens. Even small abiotic shifts, associated with climate change, are likely to have pronounced impacts on these communities that currently exist at their physiological limit of survival. Changes to moisture availability, due to precipitation shifts or alterations to permanent snow reserves, will most likely cause greatest impact. In order to establish a baseline for determining the effect of climate change on continental Antarctic terrestrial communities and to better understand bryophyte species distributions in relation to moisture in a floristically important Antarctic …

A Survey On Bio-Inspired Algorithms For Web Service Composition, Lijuan Wang, Jun Shen, Jianming Yong

Dr Jun Shen

Web service composition has become a promis- ing technology in a variety of e-science or e-business areas. There are a variety of models and methods to deal with this issue from di#11;erent aspects. Bio-inspired algorithms are becoming main approaches and solutions. This paper reviews the current researches on web service composition based on bio-inspired algorithms, such as Ant Colony Opti- mization(ACO), Genetic Algorithm(GA), Evolutionary Al- gorithm(EA) and Particle Swarm Optimization(PSO). By analyzing and investigating di#11;erent approaches, this paper gives an overview about the researches on bio-inspired al- gorithm in web service composition and point out future directions.

Adaptive Task Allocation For P2p-Based E-Services Composition, Jun Shen, Shuai Yuan

Dr Jun Shen

To effectively manage the task allocation, especially when handling with numerous different peers’ qualities, is one of the greatest challenges to be faced in order to guarantee the success of P2P-based e-services composition. In this context, various QoS descriptive frameworks and Web services technologies (such as WSDL and BPEL) are being considered as the most affordable solutions to promote the performance of decentralized e-services, through applying strategies like QoS ontologies and related optimization algorithms globally or locally. Nonetheless, most P2P-based service selection and composition approaches applied nowadays lack dynamism and autonomy. In this paper, we first propose an extension of …

Amplitude Equations For Polycrystalline Materials With Interaction Between Composition And Stress, Alain Karma

Alain Karma

We investigate the ability of frame-invariant amplitude equations [G. H. Gunaratne, Q. Ouyang, and H. Swinney, Phys. Rev. E 50, 2802 (1994)] to describe quantitatively the evolution of polycrystalline microstructures and we extend this approach to include the interaction between composition and stress. Validations for elemental materials include studies of the Asaro-Tiller-Grinfeld morphological instability of a stressed crystal surface, polycrystalline growth from the melt, grain boundary energies over a wide range of misorientation, and grain boundary motion coupled to shear deformation. Amplitude equations with accelerated strain relaxation in the solid are shown to model accurately the Asaro-Tiller-Grinfeld instability. Polycrystalline growth …

Predicting The Behavior Of A Highly Configurable Component Based Real-Time System, Gabriel A. Moreno, Scott A. Hissam, Daniel Plakosh, Isak Savo, Marcin Stelmarczyk

Gabriel A. Moreno

Software components and the technology supporting component based software engineering contribute greatly to the rapid development and configuration of systems for a variety of application domains. Such domains go beyond desktop office applications and information systems supporting e-commerce, but include systems having real-time performance requirements and critical functionality. Discussed in this paper are the results from an experiment that demonstrates the ability to predict deadline satisfaction of threads in a real-time system where the functionality performed is based on the configuration of the assembled software components. Presented is the method used to abstract the large, legacy code base of the …