Physical Sciences and Mathematics Commons^™

Reasoning About The Behavior Of Aspect-Oriented Programs, Neelam Soundarajan, Raffi T. Khatchadourian, Johan Dovland

Publications and Research

Aspect-oriented programming (AOP) has become increasingly popular over the last few years. At the same time, reasoning about the behavior of these programs poses serious challenges. In this paper, we present a rely-guarantee approach to such reasoning. The rely-guarantee approach has proven useful in reasoning about concurrent and distributed programs. We show that some of the key problems encountered in reasoning about aspect-oriented programs are similar to those encountered in reasoning about concurrent programs; and that the rely-guarantee approach, appropriately modified, helps address these problems. We illustrate our approach with a simple example.

An Update On Groundwater Conditions At The Site Of The York College Cuny Campus In Southeastern Queens County, New York City, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Edward A. Molteni

Publications and Research

The wells operated by the Jamaica Water Supply Company in Queens represent the only large scale utilization of groundwater for public water supply in New York City in recent years. These wells were shut down, for the most part, beginning in 1996. Since that time, water table elevations in the area, which had been drawn down by the withdrawal activity of the Jamaica Water Supply Company, have risen significantly causing some high groundwater problems, including flooding of basements. The New York City Department of Environmental Protection (NYCDEP) has held public hearings on a contemplated resumption of ground water withdrawal in …

Automated Refactoring Of Legacy Java Software To Enumerated Types, Raffi T. Khatchadourian, Jason Sawin, Atanas Rountev

Publications and Research

Modern Java languages introduce several new features that offer significant improvements over older Java technology. In this article we consider the new enum construct, which provides language support for enumerated types. Prior to recent Java languages, programmers needed to employ various patterns (e.g., the weak enum pattern) to compensate for the absence of enumerated types in Java. Unfortunately, these compensation patterns lack several highly-desirable properties of the enum construct, most notably, type safety. We present a novel fully-automated approach for transforming legacy Java code to use the new enumeration construct. This semantics-preserving approach increases type safety, produces code that is …

1139-3159_Nir_Spex, Dagny L. Looper

Publications and Research

No abstract provided.

A Dynamic-Trend Exponential Smoothing Model, Don Miller, Dan Williams

Publications and Research

Forecasters often encounter situations in which the local pattern of a time series is not expected to persist over the forecasting horizon. Since exponential smoothing models emphasize recent behavior, their forecasts may not be appropriate over longer horizons. In this paper, we develop a new model in which the local trend line projected by exponential smoothing converges asymptotically to an assumed future long-run trend line, which might be an extension of a historical long-run trend line. The rapidity of convergence is governed by a parameter. A familiar example is an economic series exhibiting persistent long-run trend with cyclic variation. This …

Automated Refactoring Of Legacy Java Software To Enumerated Types, Raffi T. Khatchadourian, Jason Sawin, Atanas Rountev

Publications and Research

Modern Java languages introduce several new features that offer significant improvements over older Java technology. In this article we consider the new enum construct, which provides language support for enumerated types. Prior to recent Java languages, programmers needed to employ various patterns (e.g., the weak enum pattern) to compensate for the absence of enumerated types in Java. Unfortunately, these compensation patterns lack several highly-desirable properties of the enum construct, most notably, type safety. We present a novel fully-automated approach for transforming legacy Java code to use the new enumeration construct. This semantics-preserving approach increases type safety, produces code that is …

Rely-Guarantee Approach To Reasoning About Aspect-Oriented Programs, Raffi T. Khatchadourian, Neelam Soundarajan

Publications and Research

Over the last few years, the question of reasoning about aspect-oriented programs has been addressed by a number of authors. In this paper, we present a rely-guarantee approach to such reasoning. The rely-guarantee approach has proven extremely successful in reasoning about concurrent and distributed programs. We show that some of the key problems encountered in reasoning about aspect-oriented programs are similar to those encountered in reasoning about concurrent programs; and that the rely-guarantee approach, appropriately modified, helps address these problems. We illustrate our approach with a simple example.

The Impact Of Receiver Aperture Design And Telescope Properties On Lidar Signal-To-Noise Ratio Improvements, Yasser Hassebo, Khaled El Sayed

Publications and Research

Range and sensitivities of lidar measurements in daylight are limited by sky background noise power (BGP). This is particularly important for Raman lidar techniques where the Raman backscattered signal is relatively weak. This often restricts Raman lidar measurements to nighttime where BGP is absent. The background noise elimination is particularly important in daytime measurements in case where full overlap between laser beam and receiver telescope field-of-view (FOV) is necessary. Results of numerical simulations for a vertically pointing Lidar show that significant improvements in Lidar signal to noise ratio (SNR) can be obtained, by minimizing the detected sky BGP. This can …

Scientists Are Urged To Look For Extraterrestrial Life Forms, Aldemaro Romero Jr., David Gilmore

Publications and Research

No abstract provided.

Towards The Computation Of The Convex Hull Of A Configuration From Its Corresponding Separating Matrix, Elie Feder, David Garber

Publications and Research

In this paper we cope with the following problem compute the size of the convex hull of a configuration C where the given data is the number of separating lines between any two points of the configuration (where the lines are generated by pairs of other points of the configuration)

We give an algorithm for the case that the convex hull is of size 3 and a partial algorithm and some directions for the case that the convex hull is of size bigger than 3.

Removing Long-Term Errors From The Avhrr–Based Brightness Temperature (Bt), Md Zahidur Rahman, Leonid Roytman, Felix Kogan

Publications and Research

Empirical distribution functions were applied for removing long-term errors from BT data derived from AVHRR sensor on NOAA environmental satellites. This paper investigates BT stability in the NOAA/NESDIS Global Vegetation Index (GVI) data set during 1982-2003. This period includes five NOAA satellites. Degradation of BT over time for each satellite was estimated for geographical location in China. The method of matching empirical distribution function (EDF) improves the time relative stability of BT data for all satellites, especially NOAA-9, -11 and -14.

On Groups Of Homological Dimension One, Jonathan Cornick

Publications and Research

It has been conjectured that the groups of homological dimension one are precisely the nontrivial locally free groups. Some algebraic, geometric and analytic properties of any potential counter example to the conjecture are discussed.

Hierarchical Linear Modeling In Organizational Research: Longitudinal Data Outside The Context Of Growth Modeling, Irvin Sam Schonfeld, David Rindskopf

Publications and Research

Organizational researchers, including those carrying out occupational stress research, often conduct longitudinal studies. Hierarchical linear modeling (HLM; also known as multilevel modeling and random regression) can efficiently organize analyses of longitudinal data by including within- and between-person levels of analysis. A great deal of longitudinal research has been conducted in the context of growth studies in which change in the dependent variable is examined in relation to the passage of time. HLM can treat longitudinal data, including data outside the context of the growth study, as nested data, reducing the problem of censoring. Within-person equation coefficients can represent the impact …

Vortices And Chaos In The Quantum Fluid, D. A. Wisniacki, E. R. Pujals, F. Borondo

Publications and Research

The motion of a single vortex originates chaos in the quantum fluid defined in Bohm's interpretation of quantum mechanics. Here we analize this situation in a very simple case: one single vortex in a rectangular billiard.

Fundamental Frequency Of Clamped Plates With Circularly Periodic Boundaries, Huseyin Yuce, Chang Y. Wang

Publications and Research

A boundary perturbation method is developed to determine the fundamental frequency of vibrating plates. The method is then applied to wavy, star shape and polygonal plates with clamped boundary conditions. Approximate analytical solutions of the fundamental frequency are obtained with an accuracy of O(e^4), where e is the deviation from the unit circle.