Qualitative and Quantitative Evaluation of Static Code Analysis Tools

poster abstractStatic code analysis (SCA) is a methodology of detecting errors in programs without actually compiling the source code to binary format and executing it on a machine. The main goal of a SCA tool is to aid developers in quickly identifying errors that can jeopardize the security and integrity of the program. With the vast array of SCA tools available, each specializing in particular languages, error types, and detection methodologies, choosing the optimal tool(s) can be a daunting task for any software developer, or organization. This, however, is not a problem associated only with SCA tools, but applies to any application domain where many tools exist and a selection of a subset of these tools is needed for effectively tackling a given problem. To address this fundamental challenge with selecting the most appropriate SCA tool for a particular problem, this research is performing a comprehensive study of different available SCA tool, both commercial and open-source. The end goal of this study is to not only evaluate how different SCA tools perform with respect to locating specific errors in source code (i.e., the quality of the tool), but to model the behavior of each SCA tool using quantitative metrics gathered from the source code, such as source lines of code (SLOC), cyclometic complexity, and function points. The behavioral model can then be used to prescreen existing (and new) source code, and select the most appropriate SCA tool, or set of SCA tools, that can identify the most errors in the source code undergoing analysis

First-principles study of orthorhombic CdTiO3 perovskite

In this work we perform an ab-initio study of CdTiO3 perovskite in its orthorhombic phase using FLAPW method. Our calculations help to decide between the different cristallographic structures proposed for this perovskite from X-Ray measurements. We compute the electric field gradient tensor (EFG) at Cd site and obtain excellent agreement with available experimental information from a perturbed angular correlation (PAC) experiment. We study EFG under an isotropic change of volume and show that in this case the widely used "point charge model approximation" to determine EFG works quite well.Comment: 4 pages, 1 figure. Accepted in Physical Review

The problem of a metal impurity in an oxide: ab-initio study of electronic and structural properties of Cd in Rutile TiO2

In this work we undertake the problem of a transition metal impurity in an oxide. We present an ab-initio study of the relaxations introduced in TiO2 when a Cd impurity replaces substitutionally a Ti atom. Using the Full-Potential Linearized-Augmented-Plane-Wave method we obtain relaxed structures for different charge states of the impurity and computed the electric-field gradients (EFGs) at the Cd site. We find that EFGs, and also relaxations, are dependent on the charge state of the impurity. This dependence is very remarkable in the case of the EFG and is explained analyzing the electronic structure of the studied system. We predict fairly anisotropic relaxations for the nearest oxygen neighbors of the Cd impurity. The experimental confirmation of this prediction and a brief report of these calculations have recently been presented [P.R.L. 89, 55503 (2002)]. Our results for relaxations and EFGs are in clear contradiction with previous studies of this system that assumed isotropic relaxations and point out that no simple model is viable to describe relaxations and the EFG at Cd in TiO2 even approximately.Comment: 11 pages, 8 figures, Revtex 4, published in Physical Review

Planning for Sustainability in Small Municipalities: The Influence of Interest Groups, Growth Patterns, and Institutional Characteristics

How and why small municipalities promote sustainability through planning efforts is poorly understood. We analyzed ordinances in 451 Maine municipalities and tested theories of policy adoption using regression analysis.We found that smaller communities do adopt programs that contribute to sustainability relevant to their scale and context. In line with the political market theory, we found that municipalities with strong environmental interests, higher growth, and more formal governments were more likely to adopt these policies. Consideration of context and capacity in planning for sustainability will help planners better identify and benefit from collaboration, training, and outreach opportunities

Valency of rare earths in RIn3 and RSn3: Ab initio analysis of electric-field gradients

In RIn3 and RSn3 the rare earth (R) is trivalent, except for Eu and Yb, which are divalent. This was experimentally determined in 1977 by perturbed angular correlation measurements of the electric-field gradient on a 111Cd impurity. At that time, the data were interpreted using a point charge model, which is now known to be unphysical and unreliable. This makes the valency determination potentially questionable. We revisit these data, and analyze them using ab initio calculations of the electric-field gradient. From these calculations, the physical mechanism that is responsible for the influence of the valency on the electric-field gradient is derived. A generally applicable scheme to interpret electric-field gradients is used, which in a transparent way correlates the size of the field gradient with chemical properties of the system.Comment: 10 page

Spatial Dynamics Of Vertical And Horizontal Intergovernmental Collaboration

Although researchers have made progress in understanding motivations behind local government collaboration, there is little research that explores the spatial dynamics of such interactions. Does the idea of collaboration travel horizontally, passed from neighbor to neighbor, or is vertical leadership from state, county, or regional actors more important in influencing local governments’ decisions to share resources and functions? What factors influence local governments’ choices to collaborate with their neighbors versus a regional entity, county, or state government? In this article, we investigate the importance of vertical and horizontal influences when local governments decide to collaborate around land use planning. Using data from a survey of Michigan local government officials, we take a spatial statistical approach to answering this question. We find widespread evidence of collaboration at multiple scales, and observe patterns of both horizontal and vertical influence. We also find that contextual factors help to explain these patterns of collaboration.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112248/1/juaf12139.pd

Municipal Waste Selection and Disposal: Evidences from Lombardy

This article exploit a data base of 1.522 observations related to Lombardy’s municipalities to run a cross sectional estimation of the drivers of MW selection. We find no evidence of a significant correlation between the percentage of selected MW selection and market variables such as the unit charge for waste management, a result probably affected by the high degree of integration existing in Lombardy among collectors and disposal operators. On the contrary, we discover robust and significant correlation with a set of geographical, socio-economic, and political variables. Among the latter ones, we have a confirmations on the influence of party competition on the percentage of household recycling, with the left wing ruling parties more addressed to it than the rivals, and on the high correlation existing between MW selection and the implementation of a unit pricing scheme. Other positive correlations with the independent variable are shown by per-capita income, while quite surprisingly the education level of citizens seems to play no role