1,741 research outputs found
Cut-elimination, substitution and normalisation
No full textDate of Acceptance: 01/2015We present a proof (of the main parts of which there is a formal version, checked with the Isabelle proof assistant) that, for a G3-style calculus covering all of intuitionistic zero-order logic, with an associated term calculus, and with a particular strongly normalising and confluent system of cut-reduction rules, every reduction step has, as its natural deduction translation, a sequence of zero or more reduction steps (detour reductions, permutation reductions or simplifications). This complements and (we believe) clarifies earlier work by (e.g.) Zucker and Pottinger on a question raised in 1971 by Kreisel.Peer reviewe
I remember teaching English at Seabrook
No full textIn this "I remember" memoir, Isabell Waugh, a former teacher at Seabrook, compares and constrasts the different groups of students she taught. She remembers that native-born American teenagers tended to be more concerned with athletics and social activities, than academic matters. In comparison, Estonian and Japanese parents did not tolerate low academic performance, so students from the two groups often competed intensely with each other for academic achievement and recognition. Isabelle recalls that the Estonians were, in general, more sophisticated and better educated. Most of the children knew 3-5 languages, and were more advanced in math and science. She sensed that some Estonian parents felt that their homes at Seabrook were temporary, and that they would be returning to Estonia at some point. The Seabrook Educational and Cultural Center has been soliciting current and past residents of Seabrook Farms for an "I remember" project. Residents are asked to create narratives regarding their experiences at Seabrook Farms. These memories help preserve the history and multi-cultural heritage of Seabrook Farms
Isabelle Bell to Susan Niemcewicz, December 23, 1800
No full textIsabelle Bell wrote to Susan U. Niemcewicz in Elizabethtown, New Jersey. Bell expressed her disappointment in not receiving a line from Susan. She sent Bell Lucretia Rephans subscription epistle, but Susan refrained from writing a letter to her. Bell did not execute any of Susan’s commissions in New York because her time there was short. Miss Resham heard that Mr. B Livingston told his sister, Mrs. J. Livingston that he would offer Bell a salary to live in his house and take charge of his children’s education. Asked if Susan what she thought of her being an author and if Susan would subscribe to a small volume that may have the good fortune to rival the poems of the immortal Scarron.https://digitalcommons.kean.edu/lhc_1800s/1143/thumbnail.jp
Interviews with Carl T. Bode, Isabelle Fritschen, Joseph H. Hirt, Mary G. Hirt, and Minnie Campbell
No full textInterviews with Carl T. Bode, Isabelle Fritschen, Joseph H. Hirt, Mary G. Hirt, and Minnie Campbell. The recording includes a variety of German-language songs. The last half of the recording is dedicated to Minnie Campbell telling about her time working for Mother Bickerdyke. The first few minutes of the recording are missing. 00:00:13 - Song, The Messenger Bird sung by Joseph H. Hirt and translated by Isabelle Fritschen 00:01:35 - Song, Birdie in the Window, sung by Mary Gertrude Hirt 00:02:59 - Story of Peter John Thielen\u27s experience in the Franco-Prussian War told by Joseph Hirt 00:05:27 - Grandfather\u27s experience with wild cattle told by Isabelle Fritschen 00:07:31 - Carl T. Bode introduction 00:08:46 - Nursery rhyme about hands 00:09:09 - The Cuckoo and the Donkey 00:09:42 - Sleep Baby Sleep 00:10:24 - Golden Evening Sun 00:11:00 - Beautiful Moon 00:12:10 - My Homeland 00:13:50 - Minnie Campbell Introduction 00:14:05 - Experiences as Mother Bickerdyke\u27s secretary 00:14:35 - Mother Bickerdyke\u27s 81st birthday celebration in Bunker Hill, KS 00:19:59 - Mother Bickerdyke\u27s portrait 00:23:55 - How Lydia Foster, Mother Bickerdyke\u27s Black maid came to live with her. 00:26:34 - Mother Bickerdyke\u27s death 00:29:34 - Mother Bickerdyke\u27s burial in Galesburg, Illinois 00:30:28 - Working for Mother Bickerdyke 00:34:01 - Going to School as a student of James Bickerdyke, Mother Bickerdyke\u27s son 00:35:26 - Decline of Bunker Hill, KS 00:37:15 - Russell stealing the county seat from Bunker Hill 00:38:09 - Closing of the Dorrance, KS bank 00:39:00 - Mother Bickerdyke\u27s personality 00:42:34 - Experience with Nina Brown Baker author of Cyclone in Calico 00:48:24 - Mother Bickerdyke Home for Widows and Children in Ellsworth, KS 00:51:13 - Post scripthttps://scholars.fhsu.edu/sackett/1014/thumbnail.jp
Formalization of Isabelle Meta Logic in NuPRL
No full textNuPRL and Isabelle are two general purpose theorem provers. Both of them are based on a version of Constructive Higher Order Type Theory. In an earlier work the author has proposed an informal semantics of Isabelle Meta Logic in an extension of NuPRL Type Theory. An automated converter, based on this semantics, has been developed, that translates Isabelle theorem statements into NuPRL. This work presents a formalization of the above semantics in NuPRL. It starts with a deep embedding of Isabelle type and term syntax into NuPRL Constructive Type Theory. Next, two internal NuPRL functions are defined. One of them maps Isabelle types into NuPRL types and the other maps Isabelle terms into elements of appropriate NuPRL types. These two functions provide an interpretation of Isabelle in NuPRL. Finally, interpretations of all Isabelle Meta Logic rules are proven as theorems in some classical extension of NuPRL Type Theory. This formalization is aimed to provide a more secure foundation for the interaction between two systems
Security modeling and correctness proof using Specware and Isabelle
No full textSecurity modeling is the foundation to formal verification which is a core requirement for high assurance systems. This thesis explores how security models can be built in a simple and expressive manner using the Metaslang specification language in Specware. The models are subsequently translated, via the Specware to Isabelle Interface, to be proven for correctness in Isabelle which is a generic, interactive theorem proving environment. It is found that the translation between Specware and Isabelle is almost seamless and there is much potential in the use of Isabelle/HOL to discharge proof obligations that arise in developing Specware specifications, although the actual proving requires substantial knowledge and experience in logical calculus.Approved for public release; distribution is unlimited.Outstanding ThesisSingapore ST Electronics Ltd. author (civilian).http://archive.org/details/securitymodeling10945383
Long-range transport of pollution to Europe : origins, chemical and transport pathways, and impact on tropospheric composition
No full textOzone (O3) and aerosols are harmful to human health. Long-range transport sources contribute to the background levels upon which local pollution builds. The goal of this thesis is to describe and quantify the respective contribution of local and long-range transported sources to the O3 and aerosol budget in the framework of European air quality management. This issue is examined using a global model of chemistry and transport, the GEOS-Chem model, constrained by several experimental datasets (e.g. trace gases and aerosol distributions, aerosol optical depth, particulate matter concentrations) taken from field experiments, ground-based sites and satellite. The capabilities of the model to reproduce O3 and aerosol patterns is first examined. The model reproduces well in general the distribution of O3 and related species over the North Atlantic/Europe area. The simulation of particulate matter smaller than 2.5 μm (PM2.5) and aerosol optical depth (AOD) over Europe is also satisfying in general, but this may reflect some compensating errors between individual components (e.g. underestimate of organic matter, and overestimate of sulphate and dust). Intercomparison between the GEOS-Chem and another global model (MOZECH) also reveals possible problems in the water vapour distribution associated with the processes which drive the vertical lifting of pollutant over continental boundary layers. Despite these (relative) deficiencies, the model provides anyway insights about the contribution of long-range transport on the O3 and aerosol loads over Europe. The impact of continental outflow on the O3 chemical tendencies over oceanic regions is quantified. Net O3 photochemical production in polluted air masses travelling over oceanic areas under the influence of continental outflow is enhanced all-year round compared to the background marine environment by 2 to 6 ppbv/day in the boundary layer and by 1 to 3 ppbv/day in the upper troposphere. The origin of O3 long-range sources and their impact on the European O3 budget, as well as the role of changing emissions on this budget over the pasts decades is further investigated. Import of North American O3 into Europe is mainly controlled by meteorological patterns and by photochemical production over the North Atlantic and thus reaches a maximum in summer. In addition, Asia contributes to long-range transported O3 pollution by the Indian summer monsoon easterly winds during summer. During the monsoon period, convection is strong and associated NOx lightning emissions also contribute to high O3 levels, especially in the Mediterranean basin. North American and Asian anthropogenic pollution contribute substantially to the annual O3 burden (integrated over the whole tropospheric column) over Europe, accounting for 11% and 8%, respectively while the European contribution only accounts for 9%. The increase in Asian emissions from 1980 to 1997 have compensated the local reduction of O3 precursors, especially in the free troposphere. Finally, the aerosol load over Europe and the contribution of long and medium-range sources including anthropogenic and biomass burning pollution from North America and mineral dust from North Africa is examined. The model was used to interpret MODIS (Moderate Resolution Imaging Spectroradiometer) AOD and observations provided by the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign over the North Atlantic and European area. Trans-Atlantic transport of aerosol is controlled by meteorological patterns and scavenging processes and reaches a maximum in spring. North American uxes of aerosols reach Europe at flower altitudes than that of O3 because a larger fraction of aerosols are scavenged in the venting from the boundary layer by frontal passages and deep convection. During high vegetation fire events in the boreal forest of Alaska and Canada, biomass burning pollution could also reach Europe at high altitudes, because a fraction of fire emissions are emitted directly in the free troposphere. Finally, the Saharan region also contributes significantly to the aerosol load over Europe. European sources contribute by 58% and 48% to the surface PM2.5 and column AOD over Europe. The second main sources are the mineral dust which represent in average 20% of the surface PM2.5 and AOD. In summer, North American anthropogenic and biomass burning emissions represent between 2 to 5% of the surface PM2.5 and AOD. The PM2.5 daily standard levels of the World Health organization (WHO) (10 μg/m3) and of the U.S. Environmental Protection Agency (EPA) (65 μg/m3) are often exceeded during dust outbreaks, especially in southern Europe. Long-range transport of anthropogenic and natural pollution is thus an important issue which should be considered in the definition of air quality standards and regulation treaties.LMC
Isabelle/DOF: Design and Implementation
No full textThis is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record17th International Conference, SEFM 2019
Oslo, Norway, September 18–20, 2019DOF is a novel framework for defining ontologies and enforcing them during document development and evolution. A major goal of DOF is the integrated development of formal certification documents (e. g., for Common Criteria or CENELEC 50128) that require consistency across both formal and informal arguments. To support a consistent development of formal and informal parts of a document, we provide Isabelle/DOF, an implementation of DOF on top of the formal methods framework Isabelle/HOL. A particular emphasis is put on a deep integration into Isabelleâs IDE, which allows for smooth ontology development as well as immediate ontological feedback during the editing of a document. In this paper, we give an in-depth presentation of the design concepts of DOFâs Ontology Definition Language (ODL) and key aspects of the technology of its implementation. Isabelle/DOF is the first ontology language supporting machine-checked links between the formal and informal parts in an LCF-style interactive theorem proving environment. Sufficiently annotated, large documents can easily be developed collabo- ratively, while ensuring their consistency, and the impact of changes (in the formal and the semi-formal content) is tracked automatically.IRT SystemX, Paris-Saclay, Franc
Modeling study of the interannual variability in global tropospheric hydroxyl radical and methane concentrations over the last two decades
No full textMethane (CH4) is a major greenhouse gas whose global warming potential is 23 times more important than carbon dioxide (CO2). CH4 concentrations have steadily increased since the beginning of the industrial era, reaching an unprecedent level (almost 1800 ppb at present times). CH4 is currently considered as a one of the major driver of the climate change and its warming potential has leaded the Kyoto protocol to plan a significative reduction of its emissions. The objective of this thesis is to examine the factors that contribute to the CH4 global budget as well as its year-to-year variations. To that purpose, we have implemented a methane simulation in a global model of chemistry and transport. Conducting a CH4 simulation requires a comprehensive set of interannual varying CH4 emission inventories as well as a year-to-year varying 3-D fields of concentrations of hydroxyl radicals (OH) that is the main sink for CH4. The first part of this thesis examines the OH interannual variation, using results from a "full-chemistry" simulation that accounts for interannual variations in emissions of the main O3 precursors (including carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbons) as well as the year-to-year variation in meteorology (e.g. atmospheric water vapor content), lightning emissions, and overhead O3 column. We calculated a global OH concentration of 1.22×106 molec cm-3 averaged over the period. We find that global OH concentrations steadily increased during the early 90's by 8% and reached a maximum in 1997. Afterward, concentrations decrease by 5%. We find that changes in water vapor concentrations, anthropogenic emissions of CO and NOx, lightning NOx emissions, and overhead ozone column all play a role in driving the OH year-to-year variations. The relative contributions of these parameters depend on the latitudinal and altitudinal regions of the troposphere. We examine in particular the influence of the 1997-1998 ENSO on the global OH concentrations. We find that the 1997-1998 ENSO resulted in a large increase in OH in the tropical areas and in the extra-tropical areas of the northern hemisphere (largely driven by an increase in water vapor) while it leads to a decrease in OH in the extra-tropical region of the southern hemisphere (that results from changes in the transport pathways that bring CO in the most southern latitudes and deplete OH). Our results (in terms of OH variability) are in contradiction to those found by other methods, especially those using inverse modeling approaches that are based on methyl chloroform (CH3CCl3) observations. This may results from poorly constrained sources. We then seek to implement a comprehensive set of CH4 emissions in our global model. We used anthropogenic CH4 emission data set of anthropogenic emissions from the International Institute of Technology (IIASA) whose emissions vary between 250 and 290 Tg/year between 1990 and 2000. We estimated biomass burning emissions, derived from an inventory of the total annual biomass burned area and emission factors that we constrained with measurements of the isotopic composition of atmospheric methane. This results in a global emissions rate of 60 Tg/year, which is much stronger than most of previous studies. We also developed a wetland scheme that accounts for soil carbon content, wetland fraction areas, soil temperature and humidity (with the three latter parameters varying interannually) and we evaluated the wetland areas with satellite-based estimates. Our global wetland emissions amount to about 150 Tg/year. We find a global CH4 lifetime of 10.6 years, which is in the range of values reported in previous studies. Comparing our results with different set of measurements gives promising results. The model reproduces well the year-to-year variation even if it slightly overestimates concentrations after 2000. By conducting different set of sensitivity simulations, we investigated the role of different parameters on the CH4 variations. We find that the long-term trend in CH4 is driven by a competition between anthropogenic emissions and tropospheric decay. Peaks of growth rate are driven by biomass burning emissions and to a lesser extend, wetland emissions. We find that even if we used increasing anthropogenic emissions during the 90s (that is in contradiction with some previous studies), reconstructing the observed year-to-year variation of CH4 concentrations was possible if one considers an increasing in OH during the 90s.LMC
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