2,054 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
Multibeam and Beam Scanning With Modulated Metasurfaces
No full textMultibeam and beam-scanning capabilities of metasurface (MTS) antennas using multiple feeds are investigated. The MTS synthesis is performed by direct inversion of an electric field integral equation (EFIE) obtained after expanding the unknown equivalent impedance profile into Fourier-Bessel basis functions. Two approaches are explored. The first one assumes a priori a discrete azimuthal symmetry in the impedance profile, so as to constrain the solution to a subspace which automatically provides multiple beams when illuminated with feeds regularly arranged along azimuth. In the second approach, there are not a priori assumptions on the impedance profile, but the systems of equations corresponding to each beam are stacked and solved simultaneously in the least-squares sense. This second approach can also be used to obtain polarization diversity. More importantly, it also enables continuous beam scanning. The latter functionality is achieved through the generation of two embedded patterns in a common azimuthal window with opposite phase slopes, followed by a continuous phasing of the two feed points. Various designs are presented in this article. All the results are validated with the method of moments (MoM)
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
An improved multiline analysis for monolithic inductors
No full textThis paper presents a new efficient multiline model for monolithic inductors. A preliminary model was developed by Huynen, which divided the spiral in sections of coupled transmission lines whose parameters are calculated by a variational principle. This model has been improved for inductors with high trace width-to-gap ratios and it has been demonstrated to be adequate for predicting S-parameters characterizing the inductor over a wide frequency band, even above its self-resonant frequency. This new design tool is shown to be useful for analyzing and optimizing inductor topologies built on both insulating and semiconducting substrates
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
Nanodevices for Microwave and Millimeter Wave Applications
No full textThe microwave and millimeter wave frequency range is nowadays widely exploited in a large variety of fields including (wireless) communications, security, radar, spectroscopy, but also astronomy and biomedical, to name a few. This Special Issue focuses on the interaction between the nanoscale dimensions and centimeter to millimeter wavelengths. This interaction has been proven to be efficient for the design and fabrication of devices showing enhanced performance. Novel contributions are welcome in the field of devices based on nanoscaled geometries and materials. Applications cover, but not are limited to, electronics, sensors, signal processing, imaging and metrology, all exploiting nanoscale/nanotechnology at microwave and millimeter waves. Contributions can take the form of short communications, regular or review papers
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
Investigation of microwave absorption mechanisms in microcellular foamed conductive composites
No full textThe paper investigates the mechanisms of microwave absorption in microcellular foamed conductive composites dedicated to protection against electromagnetic interferences (EMI). A multi-layered electromagnetic one-dimensional (1D) model mimicking the microcellular foam structure is built and validated using previous measurements carried out on various fabricated composite foams. Our model enables us to perform a parametric analysis of the absorption behaviour in a foamed composite, using as parameters the size of the hollow cell, the thickness of the cell’s walls and its conductivity, as well as the overall thickness of the composite and the frequency. Our investigations demonstrate that multiple reflections of the microwave signal between the cellular walls are not the main mechanism responsible for absorption, although they are often reported as a cause of enhanced absorption in the literature. On the contrary, our work demonstrates that the enhancement of the absorption observed in foamed conductive composite compared to unfoamed composite is mainly due to the presence of air in the microcells of the composite
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