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This paper is to investigate the extent and speed of the spread of the coronavirus disease 2019 (COVID-19) pandemic in the United States (US). For this purpose, the fractional form of the susceptible-exposed-infected-recovered-vaccinated-quarantined-hospitalized-social distancing (SEIR-VQHP) model is initially developed, considering the effects of social distancing, quarantine, hospitalization, and vaccination. Then, a Monte Carlo-based back analysis method is proposed by defining the model parameters, viz. the effects of social distancing rate (α), infection rate (β), vaccination rate (ρ), average latency period (γ), infection-to-quarantine rate (δ), time-dependent recovery rate (λ), time-dependent mortality rate (κ), hospitalization rate (ξ), hospitalization-to-recovery rate (ψ), hospitalization-to-mortality rate (ϕ), and the fractional degree of differential equations as random variables, to obtain the optimal parameters and provide the best combination of fractional order so as to give the best possible fit to the data selected between January 20, 2020 and February 10, 2021. The results demonstrate that the number of infected, recovered, and dead cases by the end of 2021 will reach 1.0, 49.8, and 0.7 million, respectively. Moreover, the histograms of the fractional order acquired from back analysis are provided that can be utilized in similar fractional analyses as an informed initial suggestion. Furthermore, a sensitivity analysis is provided to investigate the effect of vaccination and social distancing on the number of infected cases. The results show that if the social distancing increases by 25% and the vaccination rate doubles, the number of infected cases will drop to 0.13 million by early 2022, indicating relative pandemic control in the US. [ABSTRACT FROM AUTHOR]

Disasters have occurred in the United States since our inception. Although we cannot know when or how the next disaster will occur, we can take measures to generally prepare for the effects of disasters. One of these measures is individual preparedness. Individuals may purchase power generators for use in the event of long-term power outages or standard AA batteries and a flashlight for short-term power outages. A struggle for both emergency managers and elected officials is convincing individuals that they should take proactive steps to prepare for the eventuality of a disaster. One policy implemented by five states has been Emergency or Disaster Preparedness Sales Tax Holidays. These states have identified a number of items deemed necessary for disaster preparedness and deemed a particular weekend each year as the "sales tax holiday." This means that individuals can purchase the goods identified by the state without paying a state sales tax during that period. The basic thought is that by removing the tax and drawing attention to preparedness, individuals may be more likely to purchase these goods and become more prepared for disaster. In this paper, I seek to understand why these sales tax holidays were enacted in these states. Were they done during a policy window after a major disaster as a reactive measure, or were they done prior to a major event as a proactive measure? An analysis of legislative policies in each state, along with an examination of presidentially declared disasters, will be used to explore these questions. [ABSTRACT FROM AUTHOR]

Discusses the outcome of the 30th International Symposium on Computer Applications in the Mineral Industries scheduled for February 2002 at Phoenix, Arizona, organized by the Society of Mining Engineers. Conference theme; Participants; Guests and presentations.

Uncertainty is known to have negative impact on financial markets through its effects on investors' decisions. In the wake of the "Great Recession", quite a few recent studies have highlighted the role of uncertainty in predicting in-sample movements of interest rates. Since in-sample predictability does not guarantee out-of-sample forecasting gains, in this paper, we used historical daily and monthly data for the US to forecast mean and volatility of interest rate. The results show that changes in uncertainty measure movements fail to add any significant statistical gains to the forecast of interest rates for the US. In other words, policy makers in the US are not likely to improve their accuracy of future movements of the policy rate's mean and volatility by incorporating information derived from changes in metrics of uncertainty. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of computing all possible order ideals and also sets connected to 1, and the corresponding border bases, for the vanishing ideal of a given finite set of points. In this context, two different approaches are discussed: based on the Buchberger–Möller Algorithm [H. M. Möller and B. Buchberger, The construction of multivariate polynomials with preassigned zeros, EUROCAM '82 Conf., Computer Algebra, Marseille/France 1982, Lect. Notes Comput. Sci. 144, (1982), pp. 24–31], we first propose a new algorithm to compute all possible order ideals and the corresponding border bases for an ideal of points. The second approach involves adapting the Farr–Gao Algorithm [J. B. Farr and S. Gao, Computing Gröbner bases for vanishing ideals of finite sets of points, in 16th Int. Symp. Applied Algebra, Algebraic Algorithms and Error-Correcting Codes. AAECC-16, Las Vegas, NV, USA (Springer, Berlin, 2006), pp. 118–127] for finding all sets connected to 1, as well as the corresponding border bases, for an ideal of points. It should be noted that our algorithms are term ordering free. Therefore, they can compute successfully all border bases for an ideal of points. Both proposed algorithms have been implemented and their efficiency is discussed via a set of benchmarks. [ABSTRACT FROM AUTHOR]

In this paper, the author aims to examine the differences in perception concerning the anxiety toward the risk among three countries — Japan, the United States of America and China. The anxiety, in this case, is triggered by uncertainty. This paper also intends to clarify the effect of information to improve people's risk management targeted on the respondents of the Chinese population focusing on earthquake disasters. The social survey using questionnaire has been carried out in order to obtain the needed quantitative data for my research project. It is interesting to conclude that both respondents in China and in the United States tend to accept the impact of uncertainty better. They have shown somewhat lower level of anxiety toward nineteen items of the risks as compared with that of the Japanese respondents. The significant effects on information designed as a part of the risk management action plan as well as the living sufficiency safeguard are clearly observed. [ABSTRACT FROM AUTHOR]

The scaling exponent of a hierarchy of cities used to be regarded as a fractional dimension. The Pareto exponent was treated as the fractal dimension of size distribution of cities, while the Zipf exponent was considered to be the reciprocal of the fractal dimension. However, this viewpoint is not exact. In this paper, I will present a new interpretation of the scaling exponent of rank-size distributions. The ideas from fractal measure relation and the principle of dimension consistency are employed to explore the essence of Pareto's and Zipf's scaling exponents. The Pareto exponent proved to be a ratio of the fractal dimension of a network of cities to the average dimension of city population. Accordingly, the Zipf exponent is the reciprocal of this dimension ratio. On a digital map, the Pareto exponent can be defined by the scaling relation between a map scale and the corresponding number of cities based on this scale. The cities of the United States of America in 1900, 1940, 1960, and 1980 and Indian cities in 1981, 1991, and 2001 are utilized to illustrate the geographical spatial meaning of Pareto's exponent. The results suggest that the Pareto exponent of city-size distributions is a dimension ratio rather than a fractal dimension itself. This conclusion is revealing for scientists to understand Zipf's law on the rank-size pattern and the fractal structure of hierarchies of cities. [ABSTRACT FROM AUTHOR]

This paper investigates community structure in the US Airport Network as it evolved from 1990 to 2010 by looking at six bi-monthly intervals in 1990, 2000 and 2010, using data obtained from the Bureau of Transportation Statistics of the US Department of Transport. The data contained monthly records of origin-destination pairs of domestic airports and the number of passengers carried. The topological properties and the volume of people traveling are both studied in detail, revealing high heterogeneity in space and time. A recently developed community structure detection method, accounting for the spatial nature of these networks, is applied and reveals a picture of the communities within. The patterns of communities plotted for each bi-monthly interval reveal some interesting seasonal variations of passenger flows and airport clusters that do not occupy a single US region. The long-term evolution of the network between those years is explored and found to have consistently improved its stability. The more recent structure of the network (2010) is compared with migration patterns among the four US macro-regions (West, Midwest, Northeast and South) in order to identify possible relationships and the results highlight a clear overlap between US domestic air travel and migration. [ABSTRACT FROM AUTHOR]

The involvement of mitochondrial dysfunction in many pathophysiological conditions and human diseases is well documented. In order to evaluate mitochondrial function in vitro, many experimental systems have been developed. Nevertheless the number of in vivo monitoring systems for the evaluation of mitochondrial activities in intact animals and patients is relatively limited. The pioneering development of the conceptual and technological aspects of mitochondrial monitoring, in vitro and in vivo, was done by the late Prof. Britton Chance (July 24, 1913-November 16, 2010) since the early 1950s. It was my privilege to join his laboratory in 1972 and collaborate with him for almost four decades. The main achievements of our collaboration are presented in this paper. Our activities included cycles of technology development, followed by its applications to study various pathophysiological conditions. In the initial stage, the first fiber-optic-based NADH fluorometer was developed. This device enabled us to monitor various organs in anesthetized animals as well as the brain of nonanesthetized small animals. Later on, the addition of various physiological parameters to NADH monitoring enabled us to correlate mitochondrial function with other cellular functions. The application of the developed technology to clinical situations was a major interest of Prof. Chance and indeed this goal was achieved in the last decade. As of today, the basic tool for NADH monitoring and the large database of results are available for large-scale experimental and clinical applications. [ABSTRACT FROM AUTHOR]

The objective of this paper is to provide the results from an experimental program to measure global imperfections and dimensional variations in cold-formed steel-lipped channel members. Measurements were conducted at seven different manufacturing plants in the United States. A total of 210 cross sections were measured for global imperfections. Each cross section was measured at three locations, and every 305 mm (12 in.) along the length. The data is used to characterize global bow, camber, and twist. The majority of the data exhibits global imperfections well approximated by a half sine-wave. Further, global bow imperfections are shown to have a systematic bias in the direction of bow. The measured data is compared with manufacturing tolerances (e.g., L/384) and assumed imperfection sizes from column curves (e.g., L/960) as utilized in design practice in the United States. The measured imperfections served as justification for tightening manufacturing tolerances in the United States (e.g., to L/960). Dimensional variation of typical cold-formed steel members is also measured and compared with tolerances. The measured data provides much needed input for nonlinear analysis of cold-formed steel structures. [ABSTRACT FROM AUTHOR]

As an important part of modern financial systems, capital market has played a crucial role on diverse social resource allocations and economical exchanges. Beyond traditional models and/or theories based on neoclassical economics, considering capital markets as typical complex open systems, this paper attempts to develop a new approach to overcome some shortcomings of the available researches. By defining the generalized entropy of capital market systems, a theoretical model and nonlinear dynamic equation on the operations of capital market are proposed from statistical dynamic perspectives. The US security market from 1995 to 2001 is then simulated and analyzed as a typical case. Some instructive results are discussed and summarized. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear mathematical model to study the effect of environmental pollution on resource biomass and human populations is proposed and analyzed. In modeling the system, it is considered that there is a limited budget to be spent on environmental cleanup and health policies. An optimal investment policy is also discussed using Pontryagin's Maximum Principle. [ABSTRACT FROM AUTHOR]

VERITAS is a ground-based gamma-ray observatory that uses the imaging atmospheric Cherenkov technique and operates in the very-high energy (VHE) region of the gamma-ray spectrum from 100 GeV to 50 TeV. The observatory consists of an array of four 12 m-diameter imaging atmospheric Cherenkov telescopes located in southern Arizona, USA. The four-telescope array has been fully operational since September 2007, and over the last two years, VERITAS has been operating with high reliability and sensitivity. It is currently one of the most sensitive VHE observatories. This paper summarizes the status of VERITAS as of October 2009, and describes the detection of several new VHE gamma-ray sources. [ABSTRACT FROM AUTHOR]

Although recently there are extensive research on currency network using minimum spanning trees approach, the knowledge about the actual evolution of a currency web in Asia is still limited. In the paper, we study the structural evolution of an Asian network using daily exchange rate data. It was found that the correlation between Asian currencies and US Dollar, the previous regional key currency has become weaker and the intra-Asia interactions have increased. This becomes more salient after the exchange rate reform of China. Different from the previous studies, we further reveal that it is the trade volume, national wealth gap and countries growth cycle that has contributed to the evolutionary topology of the minimum spanning tree. These findings provide a valuable platform for theoretical modeling and further analysis. [ABSTRACT FROM AUTHOR]

Nutrients, such as nitrate, nitrite, and phosphorus, are common contaminants in many aquatic systems in the United States. Ammonia and nitrate are both regulated by the drinking water standards in the US primarily because excess levels of nitrate might cause methemoglobinemia. Phosphorus might become sources of the eutrophication problems associated with toxic algae in the freshwater bodies. Toxic algal blooms can cause severe acute and chronic public health problems. Chemical reduction of nitrate by using zero-valent iron started as early as 1964, and considerable research reports relating to this technology to nanomaterial were extensively reported in 1990s making the use of nanoscale zero-valent iron (NZVI) particles for nitrate removal become one of the most popular technologies in this field. The purpose of the present study was to examine the potential of integrating green sorption media, such as sawdust, limestone, tire crumb, and sand/silt, with two types of nanoparticles, including NZVI and Titanium Dioxide (TiO2), for nitrate removal in an engineering process. The study consists of running packed bed column tests followed by the addition of NZVI and TiO2 to improve nitrate and phosphorus removal efficiency. Preliminary results in this paper show that the potential and advanced study may support the creation of design criteria of stormwater and groundwater treatment systems for water reuse in the future. [ABSTRACT FROM AUTHOR]

This paper extends the work in [Serletis & Shintani, 2003; Elder & Serletis, 2007; Koustas et al.; Hinich & Serletis, 2008] by re-examining the empirical evidence for random walk type behavior in the US stock market. In doing so, it uses daily data on the Dow Jones Industrial Average, over the period from January 3, 1928 to March 15, 2006, and a statistical-physical approach — "detrended fluctuations analysis" — providing a reliable framework for testing the information efficiency in financial markets as shown by Uritskaya [2005a, 2005b] and Uritskaya and Uritsky [2001]. The approach eliminates nonstationary market trends and focuses on the intrinsic correlation structure of stock market fluctuations at different time scales which is studied relative to random walks models. Our results indicate that the US stock market operates close to the state predicted by the efficient markets hypothesis. The observed transient deviations from this state are shown to have a statistical origin, consistent with a purely random geometric Brownian motion. [ABSTRACT FROM AUTHOR]

NASA, NSF, and the Department of Energy established the Dark Energy Task Force to examine the opportunities for exploration of dark energy and to report on the various techniques that might be employed to further our understanding of this remarkable phenomenon. The Task Force examined dozens of white papers outlining the plans of teams to measure dark energy's properties. I present here the findings and recommendations of the Task Force. Our methodology is explained in another talk at this conference. [ABSTRACT FROM AUTHOR]

Space offers eight distinct paths to controlled laboratory-style experiments in fundamental physics beyond the reach of any Earth-based laboratory. This impressive range of opportunity has already led to important physics but we are only at the beginning. Meanwhile, NASA is in crisis. This paper follows the wisdom of a great and inspiring physicist, William Fairbank, that every setback or difficulty is an opportunity. NASA needs new science; fundamental physics can provide it and with it fascinating new technologies — and training for a new generation of imaginative physicists and engineers. [ABSTRACT FROM AUTHOR]

This paper describes the high-energy-physics program at the US Department of Energy. The mission and goals of the program are described along with the breadth of the overall program. Information on recommendations from community-based panels and committees is provided. Finally, details about the main astrophysics and cosmology projects are given. [ABSTRACT FROM AUTHOR]

The objective of this paper is to study the global dynamics of a simple SI model with two explicit age groups and apply the findings to the HIV dynamics in the United States. Specifically, we would like to explore the long term HIV dynamics to answer questions such as what will happen to human population level if all the demographical and epidemiological parameters stay constant. We also wonder if treatment alone will actually slow the spread of HIV or not. We divide the population into juvenile and adult groups. Only adults are assumed to be sexually active and we implicitly assume that the sex ratio is constant. We also assume that infected adults may produce both susceptible newborns and infected newborns. The model is fit with parameters from the HIV epidemic in the US. It produces an optimistic outcome: if nothing changes, the USA infected population may be halved in about 20 years. However, if treatment is found to extend the life expectance of infected individuals to 30 years or more, then the number of infected adults may actually increase in the next 20 years or so. This creates a dilemma: to treat or not to treat? [ABSTRACT FROM AUTHOR]

In this paper, a fast chaos-based pseudo-random number generator (PRNG) is proposed for secured communications. In order to achieve fast throughput and facilitate hardware realization, 32-bit fixed point representation and arithmetic are used. Even under such configuration with quantization errors which will make the normal chaos-based PRNG impractical, our scheme can pass all the statistical tests in the up-to-date National Institute of Standards and Technology (NIST) test suite with the output bit rate up to 134 Mbps in a 2.6 GHz Pentium-4 machine. With such a fast PRNG, a stream cipher is hence designed for the application of online secure voice communication system with User Datagram Protocol (UDP). [ABSTRACT FROM AUTHOR]

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

Many neural network methods used for efficient classification of populations work only when the population is globally separable. In situ classification of highway vehicles is one of the problems with globally nonseparable populations. This paper presents a systematic procedure for setting up a probabilistic neural network that can classify the globally nonseparable population of highway vehicles. The method is based on a simple concept that any set of classifiable data can be broken down to subclasses of locally separable data. Hence, if these locally separable data can be identified, then the classification problem can be carried out in two hierarchical steps; step one classifies the data according to the local subclasses, and step two classifies the local subclasses into the global classes. The proposed approach was tested on the problem of classifying highway vehicles according to the US Federal Highway Administration standard, which is normally handled by decision tree methods that use vehicle axle information and a set of IF-THEN rules. By using a sample of 3326 vehicles, the proposed method showed improved classification results with an overall misclassification rate of only 2.9% compared to 9.7% of the decision tree methods. A similar setup can be used with different neural networks such as recurrent neural networks, but they were not tested in this study especially since the focus was for in situ applications where a high learning rate is desired. [ABSTRACT FROM AUTHOR]

In this paper we propose a simple forecasting strategy which exploits the multiresolution property of the wavelet transform. US aggregate retail sales data have strong trend and seasonal patterns, providing a good testing ground for the proposed forecasting method. First a wavelet transform is used to decompose the time series into varying scales of resolution so that the underlying temporal structures of the original time series become more tractable; the decomposition is additive in details and approximation. Then a forecasting engine (neural network or fuzzy inference system) is trained on each of the relevant resolution scales, and individual wavelet scale forecasts are recombined to form the overall forecast. Substantial information in both the dynamic nonlinear trend and seasonal patterns of the time series is efficiently exploited: we choose short past windows for the inputs to the forecasting engines at lower scales and long past windows at higher scales. The forecasting engines learn the mapping hierarchically: using a scale-recursive strategy, we combine only those scales where significant events are detected. Univariate simulation results on US aggregate retailing indicate that the proposed method fares favourably in relation to forecasting results obtained by training a neural network on original time series. Multivariate simulation results obtained by including structural components inflation, recession, interest rates, unemployment, show improvement in sales-trend forecast. [ABSTRACT FROM AUTHOR]

This paper presents a simplified approximate analysis of the overall collapse of the towers of World Trade Center in New York on September 11, 2001. The analysis shows that if prolonged heating caused the majority of columns of a single floor to lose their load carrying capacity, the whole tower was doomed. Despite optimistic simplifying assumptions, the structural resistance is found to be an order of magnitude less than necessary for survival. [ABSTRACT FROM AUTHOR]

The measurement of methane content and air quantity in each mine return airway is performed periodically in all underground coal mines in the United States. These periodic measurements are then combined to estimate the annual emission of methane into the atmosphere. A statistical study of some Appalachian underground coal mines with moderate to high levels of methane was conducted to determine the potential errors in annual emissions calculations. This paper analyses the accuracy and precision of annual methane emission calculations by assessment of each set of measurements used to produce an annual estimate. This includes analysis of the methane content determinations, the air quantity measurements, and the calculations to determine the annual emission. The final combination of measured values is tested by simulating annual emission calculations using the Monte Carlo method. Finally, the effect of each of these three variables on the annual emission values is evaluated and conclusions are made. [ABSTRACT FROM AUTHOR]

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

In this article, we report on on investigations of the in-medium meson-nucleon interaction for the ω, ɸ, and $K_s^0$ mesons. Their in-medium cross sections and collisional widths can be measured by their absorption in a nucleus. In Hall B at the Thomas Jefferson National Accelerator Facility (JLab), the CLAS detector was used to study these long-lived mesons in nuclei. All of the mesons were produced by a photon beam with Eγ < 4 GeV in targets of 2H, C, Fe, and Pb. The vector mesons were reconstructed through their decay into e+e-. The $K_s^0$ mesons were measured with their dominant π+π- decay. The in-medium widths of the ω and ɸ mesons are found to be substantially larger than their values from the elementary reaction with a free nucleon. The analysis with the $K_s^0$ is preliminary, and its status will be discussd in this paper. [ABSTRACT FROM AUTHOR]

Presents a series of literary papers from the U.S.-based Workshop on Advances in Parallel and Distributed Computational Models, published in the February 2003 issue of 'International Journal of Foundations of Computer Science.' Features of the workshop; Method for selecting literary papers for the issue.

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to: Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to: V. Kreinovich, Department of Computer Science, University of Texas, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@cs.utep.edu, or by regular mail to: Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA. [ABSTRACT FROM AUTHOR]

Introduces a series of articles based on papers presented at the 14th Association of Computing Machinery Symposium on Computational Geometry held in Minneapolis, Minnesota on June 7-10, 1998, published in the June 2001 issue of the 'International Journal of Computational Geometry & Applications.'