Viewpoint consistency in Z and LOTOS: A case study

Specification by viewpoints is advocated as a suitable method of specifying complex systems. Each viewpoint describes the envisaged system from a particular perspective, using concepts and specification languages best suited for that perspective. Inherent in any viewpoint approach is the need to check or manage the consistency of viewpoints and to show that the different viewpoints do not impose contradictory requirements. In previous work we have described a range of techniques for consistency checking, refinement, and translation between viewpoint specifications, in particular for the languages LOTOS and Z. These two languages are advocated in a particular viewpoint model, viz. that of the Open Distributed Processing (ODP) reference model. In this paper we present a case study which demonstrates how all these techniques can be combined in order to show consistency between a viewpoint specified in LOTOS and one specified in Z. Keywords: Viewpoints; Consistency; Z; LOTOS; ODP

IMPACTS ON PROPERTY TAXES OF RECLASSIFYING FLOOD-PRONE CROPLAND IN THE SOUTH DELTA AREA OF MISSISSIPPI

Current tax appraisal procedures for cropland in Mississippi do not account for any negative impacts caused by frequent flooding in some areas of the South Delta. If flood-prone cropland values are significantly below average, the current tax system could generate inequitable tax burdens on owners of flood-prone cropland. A modified system of appraisal may be desirable to produce a more equitable tax structure. The purpose of this study was to evaluate different methods of reclassifying flood-prone cropland in the South Delta and to determine subsequent tax impacts on landowners and county tax revenue. Cropland tax data for Sharkey and Issaquena Counties were collected and different permanent reclassification schemes were proposed. Reclassification schemes were defined by lowering a parcel's capability class assignment by 1, 2, 3, or 4 classes if its elevation was below a specified trigger level. The impact that each reclassification scheme would have on landowners' taxes and the tax base in the affected counties was then estimated. In order to show the impact on tax shifts that would keep the county's tax base from declining, a new, higher millage rate was computed for selected reclassification schemes. After applying the adjusted millage rate to all properties in the county, changes in cropland taxes were reduced. Among the permanent reclassification schemes evaluated in this study, a trigger elevation level of 90 feet appears to offer reasonable tax impacts. Cropland parcels below 90 feet could be reassigned to the lowest capability class if the residents desired to provide the largest tax relief to these property owners. A more conservative reassignment scheme could be selected if desired. A temporary (year-to-year) reclassification system may provide more equitable tax distributions over time but would probably require more administrative costs to implement.Cropland appraisal, property taxes, flood-prone cropland, Land Economics/Use,

Supporting ODP - Translating LOTOS to Z

This paper describes a translation of full LOTOS into Z. A common semantic model is defined and the translation is proved correct with respect to the semantics. The motivation for such a translation is the use of multiple viewpoints for specifying complex systems defined by the reference model of the Open Distributed Processing (ODP) standardization initiative. The postscript version available here is an extended version of what was published

Multiparton Interactions in Photoproduction at HERA

The high energy photoproduction of jets is being observed at the ep collider, HERA. It may be that the HERA centre-of-mass energy is sufficiently large that the production of more than one pair of jets per ep collision becomes possible, owing to the large number density of the probed gluons. We construct a Monte Carlo model of such multiparton interactions and study their effects on a wide range of physical observables. The conclusion is that multiple interactions could have very significant effects upon the photoproduction final state and that this would for example make extractions of the gluon density in the photon rather difficult. Total rates for the production of many (i.e. > 2) jets could provide direct evidence for the presence of multiple interactions, although parton showering and hadronization significantly affect low transverse energy jets.Comment: 21 pages, 8 figures include

Relations in the Unseen : An Asexual Reading of Long Nineteenth Century British Literature

Media production will often sexualize their products, creating an encumbrance to asexual representation, all under the guise that “sex sells.” Because of that belief in the selling power of sexualization, there has been little asexual representation, preventing people from understanding asexuals or even realizing they are asexual. It wasn’t until the mid-twentieth century that asexuality came to mean feeling no, little, or conditional sexual attraction. Accepting that asexuality is, at least in some part, inherent and that aspects of life that lack the adequate language to be explicitly stated are still capable of being artistically expressed, then it follows that there are asexual characters and asexual stories that were created prior to the mid-twentieth century. This enables readers to find intersections between implicitly expressed asexuality and literature. My research is a re-imagining of established queer theory through the lens of asexuality. I then take that new critical framework and apply it to long nineteenth century British Literature, before the term “asexual” gained its meaning as we understand it today, and identify potentially asexual characters and narratives. The readings conducted discover new ways to read characters like Emma Woodhouse and Aurora Leigh. But, beyond that, these readings also explore new ways of being that are not bound by compulsory sexuality. The implications of this research are two-fold: first, to reclaim a compendium of lost texts as “asexual literature” in much the same way feminist literary theory did in the sixties and seventies; secondly, to dispel the modern notion that sex is integral to every person’s happiness and well-being and illustrate that asexual characters can be a core component to media that is compelling, popular, and profitable. By dispelling that myth, this research will encourage modern media production to reconsider asexuality in their work. Those works will contribute to making asexuality more visible so that the next generation of asexuals will not have to struggle for decades before they finally realize who they are

On the existence of finite-energy lumps in classic field theories

We show how the existence of non-trivial finite-energy time-dependent classical lumps is restricted by a generalized virial theorem. For simple model Lagrangians, bounds on energies follow.Comment: 4 pages, 1 figure; substantial change

Quark fragmentation functions in a diquark model for proton and Λ\Lambda hyperon production

A simple quark-diquark model for nucleon and $\Lambda$ structure is used to calculate leading twist light-cone fragmentation functions for a quark to inclusively decay into P or $\Lambda$. The parameters of the model are determined by fitting to the known deep-inelastic structure functions of the nucleon. When evolved from the initial to the final $Q^2$ scale, the calculated fragmentation functions are in remarkable agreement (for $z>0.4$) with those extracted from partially inclusive $ep$ and $e^+ e^-$ experiments at high energies. Predictions are made, using no additional parameters, for longitudinally and transversely polarized quarks to fragment into p or $\Lambda$.Comment: 15 pages, latex, figures may be obtained by writing to hafsa%png-qau%[email protected]

Identification of the ATPase Subunit of the Primary Maltose Transporter in the Hyperthermophilic Anaerobe \u3ci\u3eThermotoga maritima\u3c/i\u3e

Thermotoga maritima is a hyperthermophilic anaerobic bacterium that produces molecular hydrogen (H2) by fermentation. It catabolizes a broad range of carbohydrates through the action of diverse ABC transporters. However, in T. maritima and related species, highly similar genes with ambiguous annotation obscure a precise understanding of genome function. In T. maritima, three putative malK genes, all annotated as ATPase subunits, exhibited high identity to each other. To distinguish between these genes, malK disruption mutants were constructed by gene replacement, and the resulting mutant cell lines were characterized. Only a disruption of malK3 produced a defect in maltose catabolism. To verify that the mutant phenotype arose specifically from malK3 inactivation, the malK3 mutation was repaired by recombination, and maltose catabolism was restored. This study demonstrates the importance of a maltose ABC-type transporter and its relationship to sugar metabolism in T. maritima. IMPORTANCE: The application and further development of a genetic system was used here to investigate gene paralogs in the hyperthermophile Thermotoga maritima. The occurrence of three ABC transporter ATPase subunits all annotated as malK was evaluated using a combination of genetic and bioinformatic approaches. The results clarify the role of only one malK gene in maltose catabolism in a nonmodel organism noted for fermentative hydrogen production. Includes supplemental material