In the decade of the 1990s, formal methods have progressed from an academic curiosity at best, and a target of ridicule at worst, to a point where the leading manufacturer of microprocessors has indicated that its next design will be formally veri ed. In this short paper, I sketch a plausible history of the developments that led to this transformation, present a snapshot of the current state of...

Linear invariants, discovered by Lake, promise to provide a versatile way of inferring phylogenies on the basis of nucleic acid sequences (the method that he called "evolutionary parsimony"). A semigroup of Markov transition matrices embodies the assumptions underlying the method, and alternative semigroups exist. The set of all linear invariants may be derived from the semigroup by using an al...

Editorial Board within it 'DONALD J. HUGHES H. BURR STEINBACH tracts a 1 KONRAD B. KRAUSKOPP WILLIAM L. STRAUS, JR. try. Besic EDWIN M. LERNER EDWARD L. TATUM a strong Editorial Staff SARAH S. DEES, LUCILLE GUINARD, NANCY S. tion to it HAMILTON, WILLIAM HASKELL, OLIVER W. HEATtration s] WOLE, YUKIE KOZAI, JUDITH B. LEVIN, ELLEN with its s E. MURPHY, BETHSABE PEDERSEN, MADELINE SCHNEIDER. NANCY ...

When evaluating logic solvers, it is essential to take into account the application domain in which they will operate. For example, a logic solver for reasoning about programs could be applied either inside a compiler to justify the validity of optimizing transformations, or in an IDE plugin to help developers find bugs in their programs. Despite the similarity of the domain, these two applicat...

Transformation to continuation-passing style (CPS) is often performed by optimizing compilers for functional programming languages. As part of the development and proof of correctness of a compiler for the mini-ML functional language, we have mechanically verified the correctness of two CPS transformations for a call-by-value λ-calculus with n-ary functions, recursive functions, data types and ...

Maize originated under warm, seasonally dry conditions of Mesoamerica, and was by human selection converted from a low-yielding progenitor species into its modern form, with a large rachis (cob) of the female inflorescence bearing up to 1,000 seeds. Maize is a C4 plant and is very efficient in water use. If subjected to water stress, however, especially during the mid-season pollination process...

In this paper we present a formalization of Abadi’s and Cardelli’s theory of objects in the interactive theorem prover Isabelle/HOL. Our motivation is to build a mechanized HOL-framework for the analysis of a functional calculus for distributed objects. In particular, we present (a) a formal model of objects and its operational semantics based on de Bruijn indices (b) a parallel reduction relat...

Data for this study were obtained with the aid of structured questionnaire. A total of 70 questionnaires were administered to the palm oil farmers/ producers with the response rate of 95.71 %. The data were analysed by the use of descriptive statistics, multiple regression and costs and returns tools. The results obtained revealed that although mechanized palm oil processors were not fully econ...

Forests in lowland Bolivia suffer from severe deforestation caused by different types of agents and land use activities. We identify three major proximate causes of deforestation. The largest share of deforestation is attributable to the expansion of mechanized agriculture, followed by cattle ranching and small-scale agriculture. We utilize a spatially explicit multinomial logit model to analyz...