Physical Sciences and Mathematics Commons^™

Evidence Of Recycling Of Lead Battery Waste Into Highly Leaded Jewelry, Jeffrey D. Weidenhamer, Micheal L. Clement

Jeffrey D. Weidenhamer

Inexpensive highly leaded jewelry, much of it imported from China, remains widely available in the United States. The source materials for these items are unknown. Due to the low cost of much of this trinket jewelry, it seems likely that scrap materials may be used in their manufacture. Thirty-nine jewelry items previously determined to contain 90% or more lead by weight were analyzed for antimony content. The average antimony content of these thirty-nine items was 3.0%. The range of antimony content in the samples was from 0.3% to 6.2% antimony by weight, with twenty-seven of the samples in the range …

Statistical Methods For Analyzing Sequentially Randomized Trials, Oliver Bembom, Mark J. Van Der Laan

Oliver Bembom

In this issue of JNCI, Thall et al. present the results of a clinical trial that makes use of sequential randomization, a novel trial design that allows the investigator to study adaptive treatment strategies. Our aim is to complement this groundbreaking work by reviewing the current state of the art of statistical methods available for such analyses. Using the data collected by Thall et al. as an example, we focus on two different approaches for estimating the success rates of different adaptive treatment strategies of interest. By emphasizing the intuitive appeal and straightforward implementation of these methods and illustrating the …

Spatial And Temporal Patterns Of Nitrogen Deposition In China: Synthesis Of Observational Data, Chaoqun (Crystal) Lu, Hanqin Tian

Chaoqun (Crystal) Lu

Anthropogenic nitrous pollutant emissions in China significantly increased during the last decades, which contributed to the accelerated nitrogen (N) deposition. In order to characterize spatial pattern of nitrogen deposition, we employed the kriging technique to interpolate sampling data of precipitation chemistry and ambient air concentration from site-network observations over China. The estimation of wet deposition in China was limited to aqueous NO3− and NH4+, while ambient NO2 was the only species involved in the predicted dry deposition fluxes. To obtain wet deposition fluxes, precipitation concentration was multiplied by 20-year mean precipitation amounts with a resolution of 10 × 10 km. …

Posterminaries: More Or Less Modern, Alexander H. King

Alexander H. King

It is yet another sign that I am aging. More and more often when young researchers hand me a written report of their research, I find myself criticizing their introductory section: “You need to start your literature survey with the original papers on this topic. Go and read…” followed by a citation to some classic of the learned literature.

The Aeroacoustics Of Turbulent Coanda Wall Jets, Caroline Lubert

Caroline P Lubert

No abstract provided.

Ocena Wpływu Planowanego Zakładu Termicznego Przekształcania Odpadów Komunalnych Na Jakość Powietrza W Krakowie, Robert Oleniacz, Maria Pilch

Robert Oleniacz

The work presents air quality impact assessment for the planned Municipal Solid Waste Incineration (MSWI) plant in Krakow with a established capacity of 255000 tons per year. The evaluation is based on assumption that air pollutant emissions from the incinerator will be at the highest allowed level resulting from emission limit values for waste incineration plants with operation time each of two planned lines 7500 hours per year. Calculation results for the one of the considered localization of the MSWI plant in Krakow (district of Nowa Huta) support the thesis that building the incineration plant of this size will not …

Neon Abundances From A Spitzer/Irs Survey Of Wolf-Rayet Stars., R. Ignace, J. P. Cassinelli, G. Tracy, E. Churchwell, H. J. G. L. M. Lamers

Richard Ignace

We report on neon abundances derived from Spitzer high resolution spectral data of eight Wolf-Rayet (WR) stars using the forbidden line of [Ne III] 15.56 μm. Our targets include four WN stars of subtypes 4–7, and four WC stars of subtypes 4–7. We derive ion fraction abundances γ of Ne²⁺ for the winds of each star. The ion fraction abundance is a product of the ionization fraction Q_i in stage i and the abundance by number A_E of element E relative to all nuclei. Values generally consistent with solar are obtained for the WN stars, and values …

Biogeographical Distribution And Natural Groupings Among Five Sympatric Wild Cats In Tropical South Asia, Mohammed Ashraf

Mohammed Ashraf

Individualized Treatment Rules: Generating Candidate Clinical Trials, Maya Petersen, Steven G. Deeks, Mark J. Van Der Laan

Maya Petersen

Individualized treatment rules, or rules for altering treatments over time in response to changes in individual covariates, are of primary importance in the practice of clinical medicine. Several statistical methods aim to estimate the rule, termed an optimal dynamic treatment regime, which will result in the best expected outcome in a population. In this article, we discuss estimation of an alternative type of dynamic regime—the statically optimal treatment rule. History-adjusted marginal structural models (HA-MSM) estimate individualized treatment rules that assign, at each time point, the first action of the future static treatment plan that optimizes expected outcome given a patient’s …

Exceptionally Preserved Jellyfishes From The Middle Cambrian, Paulyn Cartwright, Susan L. Halgedahl, Jonathan R. Hendricks, Richard D. Jarrard, Antonio C. Marques, Allen G. Collins, Bruce S. Lieberman

Jonathan R. Hendricks

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (~505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish …

From Dataveillance To Überveillance (Uberveillance) And The Realpolitik Of The Transparent Society, K. Michael, M. G. Michael

Professor Katina Michael

The 2007 Workshop on the Social Implications of National Security: from Dataveillance to Überveillance and the Realpolitik of the Transparent Society was organised by the Research Network for a Secure Australia (RNSA) funded by the Australian Research Council. The Workshop will become a biennial event bringing together both researchers and practitioners in the fields relating to the national research priority entitled Safeguarding Australia. In 2007, the workshop was held on the 29th October, at the Function Centre at the University of Wollongong between 8.30 am and 5.00 pm.

The Workshop was organised by RNSA members from the IP Location-Based Services …

From Dataveillance To Überveillance (Uberveillance) And The Realpolitik Of The Transparent Society, K. Michael, M. G. Michael

M. G. Michael

The 2007 Workshop on the Social Implications of National Security: from Dataveillance to Überveillance and the Realpolitik of the Transparent Society was organised by the Research Network for a Secure Australia (RNSA) funded by the Australian Research Council. The Workshop will become a biennial event bringing together both researchers and practitioners in the fields relating to the national research priority entitled Safeguarding Australia. In 2007, the workshop was held on the 29th October, at the Function Centre at the University of Wollongong between 8.30 am and 5.00 pm.

The Workshop was organised by RNSA members from the IP Location-Based Services …

Differences In Electrochemical Properties Of Contact Printed And Solution Adsorbed Alkanehtiol Self-Assembled Monolayers On Gold, Leslie Adamczyk, Mark Anderson

Mark R. Anderson

No abstract is currently available.

Effects Of Potential On Ionic Self-Assembly Of Carboxylic Acid Terminated Monolayers, Wesley Sanders, Mark Anderson

Mark R. Anderson

No abstract is currently available.

Electric Power: Cyber And Electromagnetic Security Issues, George H. Baker

George H Baker

Electric power is essential to the functioning of U.S. society. The electric power system increasingly operates at or near its reliability limits. The geographic scale of the tightly coupled networks involved makes the system susceptible to large-scale outages. More frequent natural and accidental failures portend possible catastrophes from intentional disruption. Deregulation has been a major factor to the lack of investment in system upgrades. Techniques to prevent attacks and reduce vulnerabilities are available and affordable.

Growth-Temperature Optimization For Low Carrier-Density In0.75Ga0.25As-Based High Electron Mobility Transistors On Inp, Paul J. Simmonds, H. E. Beere, D. A. Ritchie, S. N. Holmes

Paul J. Simmonds

Two-dimensional electron gases (2DEGs) were formed in undoped In_0.75Al_0.25As / In_0.75Ga_0.25As / In_0.75Al_0.25As quantum wells. The optimal growth temperature for this structure is 410°C, with peak 2DEG electron mobility and density values of μ = 221000 cm²/V s and n = 1.36 × 10¹¹ cm⁻² at 1.5 K. This electron mobility is equal to the highest previously published for these undoped structures but with a factor of 2 reduction in n. This has been achieved through the use of a significantly thinner InAlAs …

Topic And Role Discovery In Social Networks With Experiments On Enron And Academic Email, Andrew Mccallum, Xuerui Wang, Andrés Corrada-Emmanuel

Andrés Corrada-Emmanuel

Previous work in social network analysis (SNA) has modeled the existence of links from one entity to another, but not the attributes such as language content or topics on those links. We present the Author-Recipient-Topic (ART) model for social network analysis, which learns topic distributions based on the direction-sensitive messages sent between entities. The model builds on Latent Dirichlet Allocation (LDA) and the Author-Topic (AT) model, adding the key attribute that distribution over topics is conditioned distinctly on both the sender and recipient---steering the discovery of topics according to the relationships between people. We give results on both the Enron …

"Conversational" Dialogues In Direct-Manipulation Interfaces, David G. Novick

David G. Novick

This paper reports ongoing research in extending direct-manipulation interfaces by incorporating, via the direct-manipulation modality itself, interaction techniques that add kinds of language features associated with spoken conversation. The paper proposes means of implementing ways for a user of a direct-manipulation system to define new kinds of relations among objects in the interface.

Users And Uses Of Synchronous Business Communications Software, David G. Novick, Eleanor Wynn

David G. Novick

To help designers and authors understand users' intentions and work practices for synchronous business communications in a systematic way, we used ethnographic and task-analytic techniques to collect, analyze and classify evidence of the activities of potential users as they conducted their work lives. The interactions we observed among our users took place through a variety of modalities. We found eight categories of tasks for the collaborative or interactive work in which our subjects engaged. Based on these data, we were able to classify roles of potential users of synchronous business communications software into a set of "archetypes" that characterize their …

Hands-Free Documentation, Karen Ward, David G. Novick

David G. Novick

In this paper, we introduce an analysis of the requirements and design choices for hands-free documentation. Hands-busy tasks such as cooking or car repair may require substantial interruption of the task: moving the pan off the burner and wiping hands, or crawling out from underneath the car. We review the need for hands-free documentation and explore the role of task in the use of documentation. Our central analysis examines the roles and characteristics of input and output modalities of hands-free documentation. In particular, we review the use of speech as an input modality, and then visual means and speech as …

An Interaction Initiative Model For Documentation, David G. Novick, Karen Ward

David G. Novick

In this paper we propose a model of creation and use of documentation based on the concept of mixed-initiative interaction. In our model, successful single-initiative interaction is characterized by grounding of contributions, and successful mixed-initiative interaction is characterized by both grounding and agreement. Just as in spoken conversation, achievement of actual agreement depends on the intentions of both parties; agreement is achieved when the reader follows the documentation’s instructions. In fact, readers are not obligated to—and often do not—act according to the author’s intentions. By making these dynamics explicit, the model can aid authors in developing effective documentation. The paper …

Assessing Effectiveness Of Personality Style In Documentation, Kenneth Sayles, David G. Novick

David G. Novick

This paper extends previous work by other researchers that indicated that users of computers preferred a computer with a personality that was similar to theirs. We conducted a similar experiment, but looking beyond preference to see if the personality of documentation would make a difference in the user’s performance. Our data suggest did not indicate that personality match affects performance; and if such a relationship exists it is likely to be weak. We discuss the related research, describe our methodology, present our results, and describe their implications and limitations.

Optimal Design Of Integrally Gated Cnt Field-Emission Devices Using A Genetic Algorithm, P. Y. Chen, Chien Hsun Chen, J. S. Wu, H. C. Wen, W. P. Wang

Chien Hsun Chen

A method to optimize the focusing quality of integrally gated CNT field-emission (FE) devices by combining field-emission modeling and a computational intelligence technique, genetic algorithm (GA), is proposed and demonstrated. In this work, the e-beam shape, as a characteristic parameter of electron-optical properties, is calculated by field-emission simulation modeling. Using a design tool that combines GA and physical modeling, a set of structural and electrical parameters for four FE device groups, including double-gate, triple-gate, quadruple-gate and quintuple-gate type, were optimized. The resultant FE devices exhibit satisfactory e-beam focusabilities and the extracted parameters with the best performance for each type of …

Fixed Points Of Abelian Actions On S2, John Franks, Michael Handel, Kamlesh Parwani

Kamlesh Parwani

We prove that if $F$ is a finitely generated abelian group of orientation preserving $C^1$ diffeomorphisms of $R^2$ which leaves invariant a compact set then there is a common fixed point for all elements of $F.$ We also show that if $F$ is any abelian subgroup of orientation preserving $C^1$ diffeomorphisms of $S^2$ then there is a common fixed point for all elements of a subgroup of $F$ with index at most two.

Simulation-Based Environment For Multi-Echelon Cyclic Planning And Optimisation, Galina Merkuryeva, Yuri Merkuryev, Liana Napalkova

Liana Napalkova

No abstract provided.

Leaded Electronic Waste Is A Possible Material For Lead-Contaminated Jewelry, Jeffrey D. Weidenhamer, Michael L. Clement

Jeffrey D. Weidenhamer

Highly leaded jewelry, often imported from China, remains widely available in the United States. Leaded electronic waste is exported from the United States to several Asian countries where solder is recovered and circuit boards are stripped of parts in small workshops. To assess whether electronic waste is being recycled into the jewelry, lead, tin and copper content of highly leaded jewelry samples were determined by atomic absorption spectrometry. Sixteen jewelry items previously determined to contain 20–80% lead by weight were analyzed. Samples were digested in nitric acid for analysis of lead and copper, and in aqua regia for analysis of …

Open Access To Professional Information, Jim Pitman

Jim Pitman

This IMS Presidential Address was given at the Joint Statistical Meetings in Salt Lake City, August 2007. There are now two competing business models for scholarly communication: the traditional Gated Access model, supported by library subscriptions, and the Open Access model, supported by some combination of author fees, sponsorship and advertising. IMS has adopted a mixed model by assisting authors to post their work on arXiv, while still retaining journal subscriptions, by allowing all journal content to become open after a suitable delay, and by supporting a mixed portfolio of gated and open journals. Providing access as openly as possible …

Usability Inspection Methods After 15 Years Of Research And Practice, Tasha Hollingsed, David G. Novick

David G. Novick

Usability inspection methods, such as heuristic evaluation, the cognitive walkthrough, formal usability inspections, and the pluralistic usability walkthrough, were introduced fifteen years ago. Since then, these methods, analyses of their comparative effectiveness, and their use have evolved in different ways. In this paper, we track the fortunes of the methods and analyses, looking at which led to use and to further research, and which led to relative methodological dead ends. Heuristic evaluation and the cognitive walkthrough appear to be the most actively used and researched techniques. The pluralistic walkthrough remains a recognized technique, although not the subject of significant further …

Toward A More Accurate View Of When And How People Seek Help With Computer Applications, David G. Novick, Edith Elizalde, Nathaniel Bean

David G. Novick

Based on 40 interviews and 11 on-site workplace observations of people using computer applications at work, we confirm that use of printed and on-line help is very low and find that providing greater detail of categories solution methods can present a more realistic picture of users’ behaviors. Observed study participants encountered a usability problem on average about once every 75 minutes and typically spent about a minute looking for a solution. Participants consumed much more time when they were unaware of a direct way of doing something and instead used less effective methods. Comparison of results from different data-collection methods …

Equatorial Ionospheric Electric Fields During The November 2004 Magnetic Storm, Bela G. Fejer, J. W. Jensen, T. Kikuchi, M. A. Abdu, J. L. Chau

Bela G. Fejer

[1] We use radar measurements from the Jicamarca Radio Observatory, magnetometer observations from the Pacific sector and ionosonde data from Brazil to study equatorial ionospheric electric fields during the November 2004 geomagnetic storm. Our data show very large eastward and westward daytime electrojet current perturbations with lifetimes of about an hour (indicative of undershielding and overshielding prompt penetration electric fields) in the Pacific equatorial region during the November 7 main phase of the storm, when the southward IMF, the solar wind and reconnection electric fields, and the polar cap potential drops had very large and nearly steady values. This result …