4,088 research outputs found
Soundly Handling Static Fields: Issues, Semantics and Analysis
Although in most cases class initialization works as expected, some static
fields may be read before being initialized, despite being initialized in their
corresponding class initializer. We propose an analysis which compute, for each
program point, the set of static fields that must have been initialized and
discuss its soundness. We show that such an analysis can be directly applied to
identify the static fields that may be read before being initialized and to
improve the precision while preserving the soundness of a null-pointer
analysis.Comment: Proceedings of the Fourth Workshop on Bytecode Semantics,
Verification, Analysis and Transformation (BYTECODE 2009
Enforcing Secure Object Initialization in Java
Sun and the CERT recommend for secure Java development to not allow partially
initialized objects to be accessed. The CERT considers the severity of the
risks taken by not following this recommendation as high. The solution
currently used to enforce object initialization is to implement a coding
pattern proposed by Sun, which is not formally checked. We propose a modular
type system to formally specify the initialization policy of libraries or
programs and a type checker to statically check at load time that all loaded
classes respect the policy. This allows to prove the absence of bugs which have
allowed some famous privilege escalations in Java. Our experimental results
show that our safe default policy allows to prove 91% of classes of java.lang,
java.security and javax.security safe without any annotation and by adding 57
simple annotations we proved all classes but four safe. The type system and its
soundness theorem have been formalized and machine checked using Coq
The impact of grazing cattle on soil physical properties and nutrient concentrations in overland flow from pasture, Part B
This report has been prepared as part of the Environmental Research Technological Development and Innovation Programme 2000â2006. The programme is financed by the Irish Government under the National Development Plan 2000â2006.End of project reportThe loss of nutrients from agricultural land to water bodies is a serious concern in many countries. To gain information on the contribution of grazing animals to diffuse nutrient losses from pasture areas to water, this study looked at the impact of cattle on nutrient concentrations in overland flow and on soil hydrology (bulk density, macroporosity and resistance to penetration). Rainfall simulations to produce overland flow were conducted and soil physical measurements were taken on experimental plots assigned to one of two treatments: 1) cattle had unrestricted access to the plot; 2) cattle could graze the plot but they could neither walk on the plot area nor deposit excrements on it. Areas to which the cattle had free access were characterised by 57%-83% lower macroporosity, by 8%-17% higher bulk density and by 27%-50% higher resistance to penetration than areas from which the cattle were excluded. The nutrients in overland flow from grassland that were affected by the presence of grazing animals were mainly the particulate nitrogen, the organic phosphorus and the potassium concentrations. Overall, the presence of cattle had a longer lasting effect on the soil hydrological parameters measured than on the nutrient concentrations in overland flow.Environmental Protection Agenc
Letter from David McDowell to Hubert Creekmore
McDowell writes on Random House, Inc. letterhead from New York City to Creekmore in Jackson, Mississippi. He writes to discuss publication and publicity for Creekmore\u27s novel, The Chain in the Heart. Includes envelope.https://egrove.olemiss.edu/creekmore/1137/thumbnail.jp
Letter from David McDowell to Hubert Creekmore
McDowell writes on Random House, Inc. letterhead from New York City to Creekmore in Jackson, Mississippi, to send an a copy of Madeline\u27s cookbook, to ask for Tony Bowers\u27 address, and to discuss Creekmore\u27s novel in progress. Includes envelope.https://egrove.olemiss.edu/creekmore/1245/thumbnail.jp
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