Готові списки джерел за темами / Extension de corps

Добірка наукової літератури з теми "Extension de corps"

Автор: Grafiati

Опубліковано: 8 червня 2024

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Статті в журналах з теми "Extension de corps":

Delon, Françoise. "Extensions séparées et immédiates de corps valués." Journal of Symbolic Logic 53, no. 2 (June 1988): 421–28. http://dx.doi.org/10.1017/s002248120002836x.

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AbstractBaur a défini la notion d'extension séparée de corps valués et montré que toute extension d'un corps maximal est séparée. Nous prouvons que, si (K, υ) est henselien et de caractéristique résiduelle nulle, alors (K, υ) ⊂ (L, w) est séparée ssi L est linéairement disjoint sur K de toute extension immédiate de K.Separated and immediate extensions of valued fields. The notion of separated extension of valued fields was introduced by Baur. He showed that extensions of maximal fields are separated. We prove that, when (K, υ) is Henselian with residual characteristic 0, then (K, υ) ⊂ (L, w) is separated iff L is linearly disjoint over K from each immediate extension of K.

MAIRE, CHRISTIAN. "PLONGEMENTS LOCAUX ET EXTENSIONS DE CORPS DE NOMBRES." International Journal of Number Theory 07, no. 03 (May 2011): 721–38. http://dx.doi.org/10.1142/s1793042111004332.

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Dans ce travail, nous nous intéressons au plongement [Formula: see text] des T-unités d'un corps de nombres K dans une partie de ses complétés p-adiques construite sur l'ensemble S. Nous montrons que l'injectivité de [Formula: see text] permet d'obtenir des informations sur la structure du groupe de Galois de certaines extensions de K où la ramification est liée à S et la décomposition à T. Nous étudions également le comportement asymptotique du noyau de [Formula: see text] le long d'une extension p-adique analytique sans p-torsion. In this article, we are interested in the embedding [Formula: see text] of the T-units of a number field K in some part of its p-adic completions at S. We show that the injectivity of [Formula: see text] allows us to obtain some information on the structure of the Galois group of some extensions of K where the ramification is attached at S and the decomposition at T. Moreover, we study the asymptotic behavior of the kernel [Formula: see text] along a p-adic analytic extension.

Folscheid, Dominique. "Corps mécanisés : extension du domaine de l’obscénité." Connexions 110, no. 2 (2018): 109. http://dx.doi.org/10.3917/cnx.110.0109.

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Thiebaud, Caroline. "Sur la capitulation dans les corps de genres d'une extension abélienne d'un corps quadratique imaginaire." Journal of Number Theory 85, no. 1 (November 2000): 92–107. http://dx.doi.org/10.1006/jnth.2000.2550.

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Laubie, François. "Ramification des groupes abéliens d’automorphismes des corps." Canadian Mathematical Bulletin 50, no. 4 (December 1, 2007): 594–97. http://dx.doi.org/10.4153/cmb-2007-057-0.

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RésuméSoit q une puissance d’un nombre premier p. Dans cette note on établit la généralisation suivante d’un théorème de Wintenberger : tout sous-groupe abélien fermé du groupe des -automorphismes continus du corps des séries formelles muni de sa filtration de ramification est un groupe filtré isomorphe au groupe de Galois d’une extension abélienne d’un corps local à corps résiduel , filtré par les groupes de ramification de l’extension en numérotation inférieure.

BLOSSIER, THOMAS, AMADOR MARTIN-PIZARRO, and FRANK O. WAGNER. "À LA RECHERCHE DU TORE PERDU." Journal of Symbolic Logic 81, no. 1 (March 2016): 1–31. http://dx.doi.org/10.1017/jsl.2015.69.

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RésuméUn groupe interprétable dans le mauvais corps vert est isogène à un quotient d’un sous-groupe définissable d’un groupe algébrique par une puissance du groupe vert. Un sous-groupe définissable d’un groupe algébrique dans un corps vert ou rouge est une extension des points colorés d’un groupe algébrique multiplicatif ou additif par un groupe algébrique. En particulier, tout groupe simple définissable dans un corps coloré est algébrique.

Gallaher, Art. "The Cooperative Extension Model." Practicing Anthropology 12, no. 4 (September 1, 1990): 18–19. http://dx.doi.org/10.17730/praa.12.4.l74734176388n6x5.

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Since the Sea Grant Marine Advisory Service (MAS) has Taken the U.S. Department of Agriculture's Cooperative. Extension Service (CES) as the model on which to, chart its future, I have been asked to comment on the latter and to generalize its implications for the former. In fairness to you who read this, I should introduce an up-front caveat: whereas I have not had; personal experience with Marine extension, my research in culture change, in this country and Ireland, has brought me into close contact with agriculture and home economics extension activity, and my tenure in university-administration, and work with the Peace Corps in its early days, further heightened my interest in CES, both as a training model and as a delivery system.

Gondard, Françoise Delon et Danielle. "XVIIème problème de Hilbert sur les corps chaîne-clos." Journal of Symbolic Logic 56, no. 3 (September 1991): 853–61. http://dx.doi.org/10.2178/jsl/1183743733.

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AbstractA chain-closed field is defined as a chainable field (i.e. a real field such that, for all n ∈ N, ΣK2n+2 ≠ ΣK2n) which does not admit any “faithful” algebraic extension, and can also be seen as a field having a Henselian valuation ν such that the residue field K/ν is real closed and the value group νK is odd divisible with ∣νK/2νK∣ = 2. If K admits only one such valuation, we show that f ∈ K(X) is in ΣK(X)2n for any real algebraic extension L of K,“f(L) ⊆ ΣL2n” holds. The conclusion is also true for K = R((t))(a chainable but not chain-closed field), and in the case n = 1 it holds for several variables and any real field K.

Mouhib, Ali. "Sur la 2-Extension Maximale Non Ramifiée de la Z2-Extension Cyclotomique de Certains Corps Quadratiques." Analele Universitatii "Ovidius" Constanta - Seria Matematica 22, no. 1 (December 10, 2014): 207–14. http://dx.doi.org/10.2478/auom-2014-0016.

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AbstractSoient ℓ et ℓ' deux nombres premiers distincts, k = Q(√ℓℓ') et k∞ la Z2-extension cyclotomique de k. Soient L∞ la 2-extension maximale non ramifiée sur k∞ et L∞ la sous-extension abélienne maximale de L∞/k∞. Sous certaines conditions sur les premiers ℓ et ℓ', nous etudions la structure des groupes de Galois Gal(L∞/k∞) et Gal(L∞/k∞).

Caillé, Arthur. "Peut-on seulement savoir ce qu’ est le corps ?" Archives de Philosophie Tome 87, no. 3 (June 21, 2023): 113–30. http://dx.doi.org/10.3917/aphi.863.0113.

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Malgré l’intérêt de Leibniz pour la physique de Huygens, leur correspondance entre 1692 et 1695 renferme plusieurs divergences révélatrices de deux ontologies différentes des corps. Selon Leibniz, les lois de Kepler peuvent être expliquées par une circulation harmonique, alors que Huygens substitue à celle-ci une pesanteur intrinsèque des corps. De plus, pour Huygens, il y a une extension dépourvue de tout corps et pourtant matérielle, ce qui n’est pas compatible avec la métaphysique de Leibniz. Enfin, Huygens explique la cohésion des corps par des atomes extrêmement durs ; Leibniz rejette de telles entités, mais complète les lois du mouvement relatif par un niveau substantiel au-delà de l’étendue.

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Дисертації з теми "Extension de corps":

Mouaha, Christophe. "Codes linéaires sur un corps fini déduits de codes sur une extension." Aix-Marseille 2, 1988. http://www.theses.fr/1988AIX22020.

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L'etude consiste a caracteriser les codes lineaires sur un corps fini obtenus comme image par homomorphisme de codes lineaires sur une extension par les transformations trace et demultiplication. Les resultats obtenus a la correction et a la detection des paquets d'erreurs sont parfois appliques. A travers les transformations precitees, on peut calculer la distribution de poids de tout code lineaire sur une extension d'un corps de galois

Mouaha, Christophe. "Codes linéaires sur un corps fini déduits de codes sur une extension." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37616702n.

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Rousseau, Édouard. "Efficient arithmetic of finite field extension." Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAT013.

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Les corps finis sont omniprésents en cryptographie et en théorie des codes, deux domaines de première importance dans les communications modernes. Ainsi, il est crucial de représenter les corps finis et d’y faire des calculs de la façon la plus efficace possible. Dans cette thèse, nous travaillons sur l’arithmétique des extensions de corps finis, de deux manières différentes et indépendantes.Dans la première partie, nous étudions l’arithmétique d’une unique extension de corps fini F_{p^k}. Lorsqu’on souhaite estimer la complexité d’un algorithme dans une extension, on compte souvent les opérations arithmétiques qui sont effectuées dans le corps de base F_p. Dans un tel modèle, toutes les opérations ont le même coût. Ce modèle est connu sous le nom de complexité algébrique. Néanmoins, on sait que la multiplication est une opération plus coûteuse que l’addition. Pour cette raison, des modèles alternatifs ont été étudiés, comme par exemple celui de la complexité bilinéaire, dans lequel on fait l’hypothèse que les additions n’ont aucun coût, et on compte donc uniquement les multiplications. Pour avoir une multiplication efficace dans l’extension F_{p^k}, des recherches ont été menées pour obtenir des formules dans lesquelles le nombre de multiplications dans le corps de base F_p est minimal. Le nombre optimal de multiplications nécessaires est, par définition, la complexité bilinéaire de la multiplication dans l’extension F_{p^k}. Trouver la valeur exacte de la complexité bilinéaire d’une extension est difficile, mais il existe des algorithmes pour chercher des formules optimales en petite dimension. Asymptotiquement, d’autres algorithmes trouvent des formules qui ne sont pas nécessairement optimales, mais qui donnent une borne supérieur linéaire en le degré de l’extension pour la complexité bilinéaire. Nous généralisons ces résultats à un nouveau type de complexité, qualifiée d’hypersymétrique, qui est liée à des formules possédant plus de symétries. Nous fournissons un algorithme pour trouver des formules hypersymmétrique, ainsi qu’une implémentation et son analyse. Nous prouvons également que la complexité hypersymmétrique est elle aussi linéaire. Dans la seconde partie, nous étudions plusieurs extensions simultanément. Dans la plupart des systèmes de calcul formel, il est possible de travailler avec des corps finis, mais deux extensions arbitraires sont souvent considérées comme des objets indépendants, et les liens entre ces extensions ne sont pas nécessairement accessibles à l’utilisateur ou l’utilisatrice. Notre but dans cette partie est de construire une structure de donnée efficace pour représenter plusieurs extensions, ainsi que les plongements entre elles. Nous voulons aussi que ces plongements soient compatibles, c’est-à-dire que si a, b, c sont trois (avec a | b | c), la composition entre les plongements de F_{p^a} vers F_{p^b} et F_{p^b} vers F_{p^c} doit être égale au plongement de F_{p^a} dans F_{p^c}. Nous appelons cette structure de donnée un réseau de corps finis compatiblement plongés. Nous donnons une implémentation de l’algorithme de Bosma-Canon-Steel, qui permet d’avoir un réseau compatible, et qui était uniquement disponible dans MAGMA. Après ce travail, nous avons ajouté cet algorithme au système de calcul formel Nemo. Une autre méthode populaire pour obtenir des réseaux compatibles vient des polynômes de Conway. C’est une manière efficace d’obtenir des plongements, mais les extensions doivent alors être définies en utilisant ces polynômes précalculés si l’on veut garantir la compatibilité. Inspiré par ces polynômes et l’algorithme de Bosma-Canon-Steel, nous proposons une nouvelle construction nommée réseau standard de corps finis compatiblement plongés. Cette dernière nous permet d’utiliser des corps finis arbitraires, tout en restant efficace. Nous analysons en détail la complexité de nos algorithmes, et donnons une implémentation montrant que notre construction peut être utilisée en pratique
Finite fields are ubiquitous in cryptography and coding theory, two fields that are of utmost importance in modern communications. For that reason, it is crucial to represent finite fields and compute in them in the most efficient way possible. In this thesis, we investigate the arithmetic of finite field extensions in two different and independent ways.In the first part, we study the arithmetic of one fixed finite field extension F_{p^k}. When estimating the complexity of an algorithm in a finite field extension, we often count the arithmetic operations that are needed in the base field F_p. In such a model, all operations have the same unit cost. This is known as the algebraic complexity model. Nevertheless, it is known that multiplications are more expensive, i.e. take more time, than additions. For that reason, alternative models were studied, such as the bilinear complexity model, in which the assumption is that additions have no cost, thus we only count the multiplications. To have an efficient multiplication algorithm in the extension F_{p^k}, research has been done to obtain formulas in which the number of multiplications in the base field F_p are minimized. The optimal number of such multiplication is, by definition, the bilinear complexity of the multiplication in F_{p^k}. Finding the exact value of the bilinear complexity of the multiplication in finite field extensions is hard, but there exist algorithms to find optimal formulas in small dimension. Asymptotically, there exist different algorithms that give formulas that are not necessarily optimal but still give a linear upper bound on the bilinear complexity in the degree of the extension. We generalize these results to a new kind of complexity, called the hypersymmetric complexity, that is linked with formulas possessing extra properties of symmetry. We provide an ad hoc algorithm finding hypersymmetric formulas in small dimension, as well as an implementation and experimental results. Generalizing the proofs of the literature, we also prove that the hypersymmetric complexity is still linear in the degree of the extension.In the second part, we work with multiple finite field extensions simultaneously. In most computer algebra systems, it is possible to deal with finite fields, but two arbitrary extensions are often seen as independent objects, and the links between them are not necessarily accessible to the user. Our goal in this part is to construct an efficient data structure to represent multiple extensions, and the embeddings between them. We also want the embeddings to be compatible, i.e. if we have three integers a, b, c such that a | b | c, we want the composition of the embeddings from F_{p^a} to F_{p^b} and F_{p^b} to F_{p^c} to be equal to the embedding from F_{p^a} to F_{p^c}. We call this data structure a lattice of compatibly embedded finite fields. We provide an implementation of the Bosma-Canon-Steel framework, a lattice of compatibly embedded finite fields that was only available in MAGMA, as well as experimental results. After this work, we also added the Bosma-Canon-Steel framework to the computer algebra system Nemo.Another popular method to obtain lattices of compatibly embedded finite fields is to use Conway polynomials. It is quite efficient but the extensions have to be defined using these precomputed special polynomials to obtain compatibility between embeddings. Inspired by both the Bosma-Canon-Steel framework and the Conway polynomials, we construct a new kind of lattice, that we call standard lattice of compatibly embedded finite fields. This construction allows us to use arbitrary finite field extensions, while being rather efficient. We provide a detailed complexity analysis of the algorithms involved in this construction, as well as experimental results to show that the construction is practical

Dos, Santos Maria Ivone. "Extension du corps, mémoire et projection : réseau d'une oeuvre et de son errance." Paris 1, 2003. http://www.theses.fr/2003PA010552.

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Cette thèse retrace la mémoire de nos déplacements de vie afin de voir de quelle manière ils nourrissent notre pensée pratique artistique. Du corps à l'oeuvre nous articulons, à travers nos propositions plastiques, les modes de projection de notre mémoire. Il s'agit de montrer que l' oeuvre est toujours une extension du corps et de son auteur et que celui -ci, en la produisant, cherche à en construire le sens en invitant, d'une certaine façon, le 'regardeur' à s'y projeter. La photographie analogique, empreinte lumineuse gravée sur un négatif ainsi que la technique de l'empreinte, contact physique porteur d'une trace, ont été les dispositifs utilisés pour prélever et transporter nos gestes sur d'autres situations. Articulant ces formes de toucher avec nos manipulations, nous avons réalisé plusieurs expériences. L'écriture de la thèse a illuminé le sentier de notre création pour dévoiler un réseau d'errance. Nous pouvons y voir comment ce réseau nous a permis de déceler la visibilité d'un système et la construction d'un espace mobile, capable à la fois de contenir la mémoire de notre parcours artistique et d'être le lieu d'articulation de nouveaux départs. Mettant en lumière un champ singulier, notre recherche a abouti à la mise en place d'une dynamique du double, d'un revenir en devenir du corps, toujours autre.

TABIOU, OURO-SAMA SAFOUANA. "Algebre geometrie d'une extension quadratique avec reference speciale aux corps de series formelles." Caen, 1987. http://www.theses.fr/1987CAEN2005.

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Etude des extensions quadratiques du point de vue algebrique et geometrique. Nous partons, dans le chapitre i, de l'idee qu'etant donne un couple de (f,f::(0)), ou f::(0) est le sous-corps associe a un automorphisme involutif tau ( +ou- id::(f)) de f, on peut toujours construire des "geometries" sur f avec f::(0) comme corps de base; le couple corps des complexes, corps des reels servant de modele et les corps de series formelles (c,r), c = k((1/t)), r = k::(0)((1/t)) avec k = k::(0)(i) et g = i**(2) n'appartient pas a k::(0)***(2), servant d'exemple. Les concepts de base poses, nous donnons les elements de la "geometrie euclidienne" sur f. Nous etudions l'intersection des "droites affines" et des cercles car ce point montre la difference qui existe entre le cas classique (f = c) et le cas general que nous traitons. Nous faisons aussi une etude de la "geometrie circulaire" sur f et nous construisons dans f, une "geometrie de poincare". Le "demi-plan de poincare" est defini comme orbite de i(f = f::(0)(i)) sous l'action de g = psl::(2)(f::(0)); nous donnons enfin des notions afin d'aboutir a une notion plus "generale" de parallelisme entre les droites hyperboliques. Nous consacrons le chapitre 2 plus particulierement aux corps de series formelles. Nous etudions l'action par transformations homographiques du groupe gl::(2)(z) (ou z est le sous-anneau k::(0)(t) de r) sur c; le but de ce travail etant d'exhiber un domaine fondamental de c pour cette action et d'en etudier la particularite; il apparait preferable de supposer que k est un corps fini (donc k = f**(2)::(q)) et de separer les cas: "-1 est un carre dans f*::(q") "-1 n'est pas un carre

Ouro-Sama, Safouana. "Algèbre géométrique d'une extension quadratique avec référence spéciale aux corps de séries formelles." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37610181p.

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Estival, Jean-Louis. "Les carcinomes différenciés du corps thyroi͏̈de avec extension laryngo-trachéale (à l'exclusion des carcinomes medullaires)." Bordeaux 2, 1993. http://www.theses.fr/1993BOR2M150.

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Leriche, Amandine. "Groupes, corps et extensions de Polya : une question de capitulation." Phd thesis, Université de Picardie Jules Verne, 2010. http://tel.archives-ouvertes.fr/tel-00612597.

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Dans cette thèse, nous nous intéressons à l'ensemble $Int\left(\mathcal O _K \right)$ des polynômes à valeurs entières sur l'anneau $\mathcal{O}_K$ des entiers d'un corps de nombres $K$. Selon Pólya, une base $\left(f_{n}\right)_{n\in \mathbb{N}}$ du $\mathcal O _K$-module $Int\left(\mathcal O _K \right)$ est dite régulière si pour tout $n \in \mathbb{N}$, $\deg(f_{n})=n$. Un corps $K$ tel que $ Int \left(\mathcal{O}_K \right)$ possède une base régulière est dit de Pólya et le groupe de Pólya d'un corps de nombres $K$ est un sous-groupe du groupe de classes de $K$ qui peut être considéré comme une mesure de l'écart pour un corps au fait d'être de Pólya. Nous étudions le groupe de Pólya d'un compositum $L= K_1 K_2$ de corps de nombres galoisiens et établissons des liens avec la ramification des nombres premiers dans chacune des extensions $K_1 /\mathbb{Q}$ et $K_2 /\mathbb{Q}$. Nous appliquons ces résultats aux corps de nombres de petit degré afin d'élargir la famille des corps de Pólya quadratiques déjà caractérisés. Par ailleurs, une condition pour qu'un corps de nombres $K$ soit de Pólya est que tous les produits d'idéaux de $K$ de même norme soient principaux. Par analogie avec le problème classique du plongement, on peut se poser la question suivante : tout corps de nombres $K$ peut-il être plongé dans un corps de Pólya? Nous donnons une réponse positive à cette question : pour tout corps $K$, le corps de classes de Hilbert $H_K$ de $K$ est un corps de Pólya . Toujours par analogie avec le problème de plongement où l'on sait que les idéaux de $\mathcal{O}_K$ deviennent principaux dans $\mathcal{O}_{H_K}$, on peut définir la notion d'extension de Pólya d'un corps $K$ : il s'agit de corps $L$ contenant $K$ dans lesquels le groupe de Pólya de $K$ devient trivial par extensions des idéaux, ce sont aussi des corps $L$ tels que le $\mathcal O _L$-module engendré par $Int\left(\mathcal O _K \right)$ possède une base régulière. Outre $H_K$ dans le cas général, dans le cas où $K$ est une extension abélienne, la capitulation des idéaux ambiges de $K$ montre que le corps de genre de $K$ en est une extension de Pólya. Ceci nous amène à des questions de minimalité et d'unicité concernant les corps et extensions de Pólya.

Dickinson, Charles R. "Refinement and extension of shrinkage techniques in loss rate estimation of Marine Corps officer manpower models/." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23375.

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This thesis is a continuation of previous work to apply modern multiparameter estimation techniques to the problem of estimating attrition rates for a large number of small inventory cells in manpower planning models used by the U.S. Marine Corps. The main advances involve the promising introduction of empirical Bayes (non-constant shrinkage) techniques, recognition of the non symmetric nature of the errors with a response to this, and some insight into all aggregation plans that should help provide greater stability for the estimation methods. In addition, the roles of some middle level methodological choices are explored. Keywords: Theses; Miller transformation inverse

Misiewicz, John M. "Extension of aggregation and shrinkage techniques used in the estimation of Marine Corps Officer attrition rates." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/25936.

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Книги з теми "Extension de corps":

Nancy, Jean-Luc. 58 indices sur le corps: Et, Extension de l'âme. Québec: Éditions Nota bene, 2004.

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Tauvel, Patrice. Corps commutatifs et théorie de Galois: Cours et exercices. Paris: Calvage et Mounet, 2008.

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Misiewicz, John M. Extension of aggregation and shrinkage techniques used in the estimation of Marine Corps Officer attrition rates. Monterey, Calif: Naval Postgraduate School, 1989.

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Dickinson, Charles R. Refinement and extension of shrinkage techniques in loss rate estimation of Marine Corps officer manpower models. Monterey, California: Naval Postgraduate School, 1988.

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U.S. Consumer Product Safety Commission, ed. Extension cords. Washington, DC: U.S. Consumer Product Safety Commission, 1994.

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Calais, Josette. Extensions de corps: Théorie de Galois : niveau M1-M2. Paris: Ellipses Édition, 2006.

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United States. Congress. Office of Compliance. Power strips and dangerous daisy chains. Washington, D.C: Office of Compliance, 2007.

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Office, General Accounting. Nuclear waste: Extensive process to site low-level waste disposal facility in Nebraska : report to the Honorable J. James Exon, U.S. Senate. Washington, D.C: U.S. General Accounting Office, 1991.

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Sakul, Kahraman. Military Engineering in the Ottoman Empire. Edinburgh University Press, 2018. http://dx.doi.org/10.3366/edinburgh/9781845861209.003.0008.

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The Ottoman Empire was largely self-sufficient in the materials of gunpowder warfare, apart from tin. In the Danube and Mediterranean basins it had access to a culture of technological transfer not least from French and Walloon deserters whom the Habsburgs did not always pay regularly. Ottoman architects such as the great Sinan Aga were mathematically informed and expected to cover secular, religious and military tasks. A centralised regime sustained a small imperial engineering corps. Its modernisation after 1720 was impeded not by prejudice but by fiscal, political and military over-extension.

Albu, Toma. Cogalois Theory. Taylor & Francis Group, 2002.

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Частини книг з теми "Extension de corps":

Serre, Jean-Pierre. "Extensions de corps ordonnés." In Springer Collected Works in Mathematics, 1–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-39816-2_1.

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Robinson, Sarah. "Corpi annidati." In La mente in architettura, 139–58. Florence: Firenze University Press, 2021. http://dx.doi.org/10.36253/978-88-5518-286-7.09.

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We are bodies start from other bodies. Yet, we rarely consider how our bodies extend into our surroundings. Discusses our body schema, peripersonal and extra personal space. Considers buildings as extensions of our bodies and minds and develops the con-cept of nested bodies that engage the senses, spatial cognition and a sense of place, audi-tory system and acoustic architecture, the haptic system and texture, tasting, smelling and the imagination, visual perception and chronobiology, atmospheric space.

Nazarenko, A., Pierre Zweigenbaum, Benoît Habert, and J. Bouaud. "Corpus-based extension of a terminological semantic lexicon." In Recent Advances in Computational Terminology, 327–51. Amsterdam: John Benjamins Publishing Company, 2001. http://dx.doi.org/10.1075/nlp.2.17naz.

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Laubie, François. "Sur La Ramification Des Extensions Infinies Des Corps Locaux." In Séminaire de Théorie des Nombres, Paris 1985–86, 97–117. Boston, MA: Birkhäuser Boston, 1987. http://dx.doi.org/10.1007/978-1-4757-4267-1_7.

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Bogdanova-Beglarian, Natalia, Tatiana Sherstinova, Olga Blinova, Olga Ermolova, Ekaterina Baeva, Gregory Martynenko, and Anastasia Ryko. "Sociolinguistic Extension of the ORD Corpus of Russian Everyday Speech." In Speech and Computer, 659–66. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43958-7_80.

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Hadley, Gregory, and Hiromi Hadley. "Chapter 7. Exploring the impact of data-driven learning in extensive reading." In Studies in Corpus Linguistics, 149–76. Amsterdam: John Benjamins Publishing Company, 2021. http://dx.doi.org/10.1075/scl.102.07had.

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Jezewski, Michal, and Jacek M. Leski. "Nonlinear Extension of the IRLS Classifier Using Clustering with Pairs of Prototypes." In Proceedings of the 8th International Conference on Computer Recognition Systems CORES 2013, 121–30. Heidelberg: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00969-8_12.

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Serre, Jean-Pierre. "Une ≪formule de masse≫ pour les extensions totalement ramifiées de degré donné d’un corps local." In Oeuvres - Collected Papers III, 447–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-39816-2_115.

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Correia, Ana Priscila Franca, Carlos Kaylan Souza Batista, Diego Bitu de Melo, Francisca Ana Lívia Rodolfo da Silva, Gleyciane Lins Pereira, Karen Maria Ferreira Tavares, Larissa Thaís de Melo Filizola, Letícia Bezerra Barroso, Ranielly Lara Corpe Teixeira, and Jalles Dantas de Lucena. "RELATO DE EXPERIÊNCIA DO PROJETO DE EXTENSÃO ANATO ACADEMY: JOVENS DO ENSINO MÉDIO APRENDENDO SOBRE O CORPO HUMANO." In Tripé do Ensino Superior: Ensino, Pesquisa e Extensão, 795–803. José de Freitas: Instituto Produzir, 2021. http://dx.doi.org/10.4322/978-65-995353-2-1.c84.

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Тези доповідей конференцій з теми "Extension de corps":

Gastopoulos, Thomai, Patricia McGinn, and Joseph Lawton. "Development and Testing of a Gas Turbine Engine Combustion Air Inlet Protection Shroud for the USMC Amphibious Combat Vehicle." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-76945.

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The Marine Corps Systems Command is evaluating alternative propulsion systems to achieve high water speed for the future USMC Amphibious Combat Vehicle (ACV). A gas turbine engine is one of the propulsion systems evaluated. The primary risk of operating a gas turbine engine in the ACV is power loss due to the ingestion of marine contaminants such as saltwater mist in the air, saltwater spray generated from the vehicle operation, green water wash caused by the operation of the vehicle in the surf zone or in rough seas, and hard particles such as sand present in the marine environment. The Auxiliary Ships and New Acquisition Support Branch (Code 425) of the Naval Surface Warfare Center, Philadelphia Division conducted a study to assist the Marine Corps Systems Command in assessing the feasibility of using a gas turbine engine as a propulsion system on future USMC ACVs. The study was focused on developing and testing a gas turbine intake solution for the ACV that can remove saltwater from the intake airstream of the notional 3,000 horsepower ACV engine. Code 425 developed a two-part solution for the intake of the ACV. The first part of the solution is the Combustion Air Protection Shroud (CAPS) located at the entrance of the engine intake and designed to protect the ACV engine from green water wash by elevating the intake above the ACV deck. The second part of the solution is a gas turbine intake filtration system located downstream of the intake shroud and designed to remove marine contaminants that enter the intake shroud. A reduced-scale model of the CAPS was designed by Code 425 in conjunction with Gibbs & Cox and tested at the Davidson Laboratory High Speed Test Basin at the Stevens Institute of Technology to determine the optimum extension height of the CAPS to protect the engine intake. This paper covers the design and testing of the CAPS. The results showed that a 2.67 ft. tall CAPS with selectively closeable air intake louvers is sufficient to keep out saltwater from the ACV gas turbine engine.

Parise, Giuseppe, Erling Hesla, Claudio S. Mardegan, Luigi Parise, and Elisabetta Bragagni Capaccini. "Series Faults in Electrical Cords and Extension Cords." In 2019 IEEE/IAS 55th Industrial and Commercial Power Systems Technical Conference (I&CPS). IEEE, 2019. http://dx.doi.org/10.1109/icps.2019.8733331.

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Parise, Giuseppe, and Luigi Parise. "Unprotected faults of electrical cords and extension cords in AC and DC systems." In 2013 IEEE/IAS 49th Industrial & Commercial Power Systems Technical Conference (I&CPS). IEEE, 2013. http://dx.doi.org/10.1109/icps.2013.6547340.

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CARVALHO, MAIARA URBANETTO N. DE, and CRISTIANE WAGNER. "MEU CORPO TAMBÉM FALA." In XXIV Simpósio de Ensino, Pesquisa e Extensão - SEPE. sepebr, 2020. http://dx.doi.org/10.48195/sepe2020-162.

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Hirschmanner, Matthias, Stephanie Gross, Brigitte Krenn, Friedrich Neubarth, Martin Trapp, Michael Zillich, and Markus Vincze. "Extension of the Action Verb Corpus for Supervised Learning." In Austrian Robotics Workshop 2018. innsbruck university press, 2018. http://dx.doi.org/10.15203/3187-22-1-13.

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Altangerel, Chagnaa, Kerey Esenbek, and Jaimai Purev. "Mongolian speech corpus extension for Text-to-Speech development." In 2013 8th International Forum on Strategic Technology (IFOST). IEEE, 2013. http://dx.doi.org/10.1109/ifost.2013.6616908.

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Amroun, S., Y. Zouari, and A. Bouattour. "Fermeture de communication bucco-sinusienne par autogreffe osseuse." In 66ème Congrès de la SFCO. Les Ulis, France: EDP Sciences, 2020. http://dx.doi.org/10.1051/sfco/20206602012.

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Introduction: les moyens thérapeutiques de gestion des communications bucco-sinusiennes s’intéressent souvent à la fermeture muqueuse de celles-ci. Rares sont les interventions qui corrigent le défaut osseux sous-jacent. Ce dernier rend difficile toute réhabilitation implantaire dans le même secteur. Il est présenté ici, à travers un cas clinique, une alternative de gestion d’une CBS et du défaut osseux associé. Et ceci grâce à une greffe osseuse autogène impactée, sans utilisation de matériel d’ostéosynthèse. Observation : le patient de 50 ans, non-fumeur, s’est présenté en consultation pour des écoulements purulents récurrents. Ces derniers sont apparus deux ans auparavant, entretenus par une communication bucco-sinusienne post extractionnelle. Bien que la communication en elle-même mesurait 1cm de grand axe sur 4mm de large (au niveau muqueux), le défaut osseux sous-jacent atteignait 13mm de grand axe sur 10mm de large. Après l’étude clinique et radiolographique rigoureuse de cette CBS, une impaction d’un greffon osseux tubérositaire autogène suivie d’une fermeture muqueuse hermétique ont été réalisées. La prise d’un greffon de forme similaire au défaut, mais de volume légèrement supérieur, a permis de fixer la greffe par impaction. Discussion: la littérature offre une large palette de technique de gestion des communications bucco-sinusiennes. La plus répandue et la plus prédictible est l’utilisation d’un lambeau vestibulaire tracté, avec ou sans traction de corps adipeux de la joue. Dans le cas décrit ici, la présence d’un édentement distal en extension du secteur concerné offrait une large possibilité de prélèvement osseux tubérositaire. Le traitement choisi a atteint ses objectifs, aussi bien sur le plan muqueux qu’osseux. Des signes de consolidation osseuse du greffon impacté ont été constatés à l’imagerie CBCT à 3 mois. Ce support osseux a permis une cicatrisation muqueuse satisfaisante, avec la présence suffisante de gencive attachée. La réhabilitation implantaire et pré-implantaire peut donc être envisagée. Conclusion : dans la gestion des communications bucco-sinusiennes, le choix de la technique opératoire détermine les possibilités de réhabilitations prothétiques ultérieures. La technique présentée peut être une alternative intéressante. En effet, le traitement prothétique, fixe ou amovible, sera toujours plus efficient avec un support osseux maxillaire reconstruit.

Iizuka, Hiroshi, and Hideo Takahashi. "Extensional Stiffness Loss of Synchronous-Belt Cords." In ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/ptg-14412.

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Abstract Synchronous belts consist of a rubber, a facing fabric and a helical cord that reinforces the belt stiffness. Therefore, the fatigue failure of the helical cord through the life is important for the stiffness loss of the belts. The purpose of this study is to discuss the mechanism of the extensional stiffness loss of the helical cord during the bending fatigue. The experimental results show that the extensional stiffness reduces up to about 50–60% of the initial value by the accumulation of the bending fatigue damage. The main damage is the de-bonding along the interfaces of the stranded glass filaments in the cord. The three dimensional FEM results show that the extensional stiffness is reduced by the initiation of the de-bonding. Then a simplified mechanical model is proposed to explain the stiffness loss considering the de-bonding. The model reasonably well explains the extensional stiffness loss.

O'Hara, William. "Phrase extension in Haydn's string quartet minuets: A preliminary corpus study." In Future Directions of Music Cognition. The Ohio State University Libraries, 2021. http://dx.doi.org/10.18061/fdmc.2021.0012.

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Camp, Joshua L., and Andrew Duggleby. "Compressible Euler Extension of a Massively-Parallel Spectral Element Solver." In ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/fedsm2012-72308.

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Current supercomputing systems have tens or hundreds of thousands of cores and are trending to GPU and co-compute platforms that deliver thousands of cores per node. Modern computational fluid dynamics codes must be designed to take advantage of these developments in order to further their use in the design cycle. Furthermore, these codes must be highly accurate, stable, and geometrically flexible. NEK5000 is a massively-parallel spectral element code that exhibits these characteristics but currently only for incompressible and low-Mach flows. Adding capabilities for NEK5000 to solve the fully compressible Navier-Stokes equations will extend its usefulness to aerospace applications. As a first step the following work extends NEK5000’s capabilities to solve the 2D compressible Euler equations. Using the conservative formulation, the equations are discretized using a non-staggered spectral element mesh, and the state variables are advanced using 1st order explicit Euler time stepping. A channel with a 10% bump is used as a test case for the modification. The modified NEK5000 code performs very well despite not being optimized for use in hyperbolic equations.

Звіти організацій з теми "Extension de corps":

Wadman, Heidi, and Jesse McNinch. Spatial distribution and thickness of fine-grained sediment along the United States portion of the upper Niagara River, New York. Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41666.

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Over 220 linear miles of geophysical data, including sidescan sonar and chirp sub-bottom profiles, were collected in 2016 and 2017 by the US Army Corps of Engineers and the US Fish and Wildlife Service in the upper Niagara River. In addition, 36 sediment grab samples were collected to groundtruth the geophysical data. These data were used to map the spatial distribution of fine-grained sediment, including volume data in certain locations, along the shallow shorelines of the upper Niagara River. Overall, the most extensive deposits were spatially associated with either small tributaries or with man-made structures that modified the natural flow of the system. Extensive beds of submerged aquatic vegetation (SAV) were also mapped. Although always associated with a fine-grained matrix, the SAV beds were patchy in distribution, which might reflect subtle differences in the grain size of the sediment matrix or could simply be a function of variations in species or growth. The maps generated from this effort can be used to guide sampling plans for future studies of contamination in fine-grained sediment regions.

Weinschenk, Craig, Daniel Madrzykowski, and Paul Courtney. Impact of Flashover Fire Conditions on Exposed Energized Electrical Cords and Cables. UL Firefighter Safety Research Institute, October 2019. http://dx.doi.org/10.54206/102376/hdmn5904.

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A set of experiments was conducted to expose different types of energized electrical cords for lamps, office equipment, and appliances to a developing room fire exposure. All of the cords were positioned on the floor and arranged in a manner to receive a similar thermal exposure. Six types of cords commonly used as power supply cords, extension cords, and as part of residential electrical wiring systems were chosen for the experiments. The non-metallic sheathed cables (NMB) typically found in residential electrical branch wiring were included to provide a link to previous research. The basic test design was to expose the six different types of cords, on the floor of a compartment to a growing fire to determine the conditions under which the cord would trip the circuit breaker and/or undergo an arc fault. All of the cords would be energized and installed on a non-combustible surface. Six cord types (18-2 SPT1, 16-3 SJTW, 12-2 NM-B, 12-3 NM-B, 18-3 SVT, 18-2 NISPT-2) and three types of circuit protection (Molded case circuit breaker (MCCB), combination Arc-fault circuit interrupter (AFCI), Ground-fault circuit interrupter (GFCI)) were exposed to six room-scale fires. The circuit protection was remote from the thermal exposure. The six room fires consisted of three replicate fires with two sofas as the main fuel source, two replicate fires with one sofa as the main fuel source and one fire with two sofas and MDF paneling on three walls in the room. Each fuel package was sufficient to support flashover conditions in the room and as a result, the impact on the cords and circuit protection was not significantly different. The average peak heat release rate of the sofa fueled compartment fires with gypsum board ceiling and walls was 6.8 MW. The addition of vinyl covered MDF wall paneling on three of the compartment walls increased the peak heat release rate to 12 MW, although most of the increased energy release occurred outside of the compartment opening. In each experiment during post flashover exposure, the insulation on the cords ignited and burned through, exposing bare conductor. During this period the circuits faulted. The circuit protection devices are not designed to provide thermal protection, and, thus, were installed remote from the fire. The devices operated as designed in all experiments. All of the circuit faults resulted in either a magnetic trip of the conventional circuit breaker or a ground-fault trip in the GFCI or AFCI capable circuit protection devices. Though not required by UL 1699, Standard for Safety for Arc-Fault Circuit-Interrupters as the solution for detection methodology, the AFCIs used had differential current detection. Examination of signal data showed that the only cord types that tripped with a fault to ground were the insulated conductors in non-metallic sheathed cables (12-2 NM-B and 12-3 NM-B). This was expected due to the bare grounding conductor present. Assessments of both the thermal exposure and physical damage to the cords did not reveal any correlation between the thermal exposure, cord damage, and trip type.

McAlpin, Tate, Gaurav Savant, Gang Zhao, John Petrie, and Madalyn Mouton. Numerical modeling of supercritical flow in the Los Angeles River : Part I : Adaptive Hydraulics numerical modeling of the 1943 physical model. Engineer Research and Development Center (U.S.), March 2023. http://dx.doi.org/10.21079/11681/46631.

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The Los Angeles District of the US Army Corps of Engineers is assisting the City of Los Angeles with restoration efforts on the Los Angeles River. The city wishes to restore portions of the channelized river to a more natural state with riparian/vegetative green spaces for both wildlife and public recreation usage. The Los Angeles River provides an important role for the City of Los Angeles from a flood-control perspective, and functionality needs to be preserved when contemplating system modifications. This report details the development of an Adaptive Hydraulics (AdH) numerical model capable of representing this complex system consisting of both subcritical and supercritical flow regimes. Due to limited hydraulic data in the study area, an extensive model validation to observed data was not possible. To bridge the data gap, a numerical model was developed from a previously completed physical model study with extensive quantitative measurements and qualitative reports of hydraulic conditions. This approach allowed engineers to evaluate the effectiveness of the AdH model in representing this complex hydraulic system along with determining the best methodology to accurately represent the existing conditions. This study determined appropriate model parameters that will be utilized in further numerical modeling efforts to evaluate system modifications associated with restoration efforts.

Keil, Karen, Trudy Estes, Joseph Kreitinger, Guilherme Lotufo, Richard Price, Burton Suedel, Michael Habberfield, et al. Environmental evaluation and management of dredged material for beneficial use : a regional beneficial use testing manual for the Great Lakes. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/45024.

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The Environmental Evaluation and Management of Dredged Material for Beneficial Use: A Regional Beneficial Use Testing Manual for the Great Lakes (a.k.a. Great Lakes Beneficial Use Testing Manual) is a resource document providing technical guidance for evaluating the suitability of dredged sediment for beneficial use in aquatic and terrestrial environments in the Great Lakes region. The procedures in this manual are based on the Environmental Laboratory extensive research, working with US Army Corps of Engineers (USACE) Great Lakes districts, state resource agencies, and local stakeholders seeking to develop dredged material beneficial use alternatives consistent with regional needs and goals. This manual is the first guidance document developed by USACE for evaluating the environmental suitability of dredged material specifically for beneficial use placements. It provides a tiered framework for evaluating the environmental suitability of aquatic and upland beneficial uses consistent with the Inland Testing Manual and the Upland Testing Manual. This manual is intended to serve as a regional platform to increase collaborative problem-solving and endorse a common understanding of the scientific and institutional practices for evaluating dredged material for any beneficial use. Dredged sediment may be managed as a valuable resource, with great potential to create economic, environmental, and social benefits.

Løvschal, Mette, Havananda Ombashi, Marianne Høyem Andreasen, Bo Ejstrud, Renée Enevikd, Astrid Jensen, Mette Klingenberg, Søren Munch Kristiansen, and Nina Helt Nielsen. The Protected Burial Mound ‘Store Vejlhøj’, Vinderup, Denmark: First Results. Det Kgl. Bibliotek, 2023. http://dx.doi.org/10.7146/aulsps-e.479.

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An archaeological excavation of the protected burial mound Store Vejlhøj in northwestern Denmark was carried out in October-November 2021. The excavation formed part of the ERC-funded research project called ANTHEA, focusing on the deep history of anthropogenic heathlands. It was conducted by Aarhus University in collaboration with Holstebro Museum and Moesgaard Museum. The aim was to test a new method of sampling pollen data from different construction stages in a burial mound and comparing them with pollen data from nearby lake sediments with a view to improving our understanding of prehistoric anthropogenic heathland dynamics. Prior to the excavation, soil cores were collected from two nearby peat sediments as well as six burial mounds (including Store Vejlhøj) within a 1 km range of Lake Skånsø, where previous pollen analyses had been carried out. Based on these preliminary corings, Store Vejlhøj was selected for further archaeological investigation. A dispensation for excavating the protected mound was granted by the Danish Palaces and Culture Agency. The excavation was based on a 5 m long trench through the barrow, moving from its foot inwards. The surface vegetation and 40 cm topsoil were removed by an excavator, after which the remainder of the trench was manually dug in horizontal layers. Observation conditions were good. The excavation revealed a series of well-defined barrow construction stages, as well as unusually wellpreserved turf structures. Only two archaeological finds could be related to the barrow, both of which were later than its initial construction: a secondary urn in the top layer, and the base of a second urn at the foot of the mound. The burial mound was constructed using a minimum of three shells, which could be observed in the trench profile. Turfs were most probably collected locally in a landscape dominated by grass pastures, where no previous turf cutting had taken place. A total of 34 soil samples were collected for paleoecological analyses (pollen, Non-Pollen Polymorphs (NPPs), macrofossils) and geoarchaeological analyses (micromorphology, bulk samples). Preliminary pollen and macrofossil results from the burial mound revealed poor preservation conditions, which prompted a trench extension of 0.5 m by 0.2 m to find better preservation conditions. This extension resulted in the collection of a single final macrofossil sample, although there was no identifiable change in the in-situ preservation conditions. The dating results of the mound have not yet been completed and will be included as appendix 4-6 in 2023.

Altman, Safra, R. Harris, S. McKay, Michael Kjelland, and Todd Swannack. Oyster reef connectivity : ecological benefits and associated vulnerabilities. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/45020.

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Global oyster abundance has declined ~85 % over the past 200 years, primarily because of overharvesting (Beck, Brumbaugh, and Airoldi 2011; Kirby 2004). Healthy oyster reef systems benefit the environment in many ways, including water-quality improvement, shoreline protection, increased biological and habitat diversity, and carbon sequestration. To maintain these environmental benefits, reef-restoration efforts that produce healthy, sustainable oyster reefs are essential. To this end, the US Army Corps of Engineers (USACE) has been involved in reef-restoration projects in many locations, including extensive efforts in the Chesapeake Bay (Virginia, Maryland), coastal regions of New York and New Jersey, and the Gulf of Mexico. There are many benefits to creating and maintaining oyster reef systems that are well connected, for both oysters and other organisms within the reef and surrounding habitats. This technical note presents the current knowledge of benefits and costs to restore oyster-reef connectivity along the East and Gulf Coasts of North America. Connectivity of oyster reefs can refer to the physical location of reefs with respect to one another as well as to the dynamics of the genetic links within a metapopulation or to the extent to which larval transport and recruitment unite reef communities. For the purposes of this technical note, connectivity is defined as the spatial aggregation of reefs, though we address impacts of genetic and larval flow as well. Reef connectivity positively affects many ecosystem services and dynamics but can also have unintended consequences (that is, negative externalities). This technical note reviews the benefits and costs of increasing connectivity and presents a brief example of how trade-offs may occur between these potentially opposing ecological objectives. Here, we focus on the eastern oyster, Crassostrea virginica, which inhabits the East and Gulf Coasts of North America, though many of the concepts and principles discussed may apply to other oyster species as well.

Alhasan, Ahmad, Brian Moon, Doug Steele, Hyung Lee, and Abu Sufian. Chip Seal Quality Assurance Using Percent Embedment. Illinois Center for Transportation, December 2023. http://dx.doi.org/10.36501/0197-9191/23-029.

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This study investigates the use of macrotexture as an indicator of the percent embedment (PE) of aggregate in a chip seal and ultimately, as a quality assurance tool for chip seals. The study included an extensive field- and controlled-testing program from 24 chip seal sections constructed in Illinois. Surface texture measurements were acquired using a high-speed texture profiler and a stationary laser texture device. The analysis showed that stationary texture measurements were more consistent and reliable for estimating PE and characterizing chip seals in the field. Moreover, the ground truth PE values were estimated using an image analysis algorithm implemented on side-view images of cores extracted in the field. The ground truth PE values were estimated using four approaches: the average elevation method, percent embedment of each aggregate method, the peak method, and the aggregate circumference method. The analysis showed that the correlations between the different PE estimation methods are relatively weak, indicating the various methods provide different information and may relate to different characteristics. The general regression models for PE values estimated using the average elevation method and the mean profile depth (MPD) acquired using laser texture scans and the average least dimension (ALD) yielded the highest R2 value of 0.50. The model showed a consistent decreasing trend between PE and MPD estimated using laser texture scans and side-view images. Moreover, the model matched the expected behavior that PE should reach 100% as MPD reaches 0. Finally, four models were recommended correlating PE estimated using the average elevation and each aggregate methods to the MPD (mm) estimated from laser texture scans and ALD (mm) estimated from side-view images.

Ruiz, Pablo, Craig Perry, Alejando Garcia, Magali Guichardot, Michael Foguer, Joseph Ingram, Michelle Prats, Carlos Pulido, Robert Shamblin, and Kevin Whelan. The Everglades National Park and Big Cypress National Preserve vegetation mapping project: Interim report—Northwest Coastal Everglades (Region 4), Everglades National Park (revised with costs). National Park Service, November 2020. http://dx.doi.org/10.36967/nrr-2279586.

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The Everglades National Park and Big Cypress National Preserve vegetation mapping project is part of the Comprehensive Everglades Restoration Plan (CERP). It is a cooperative effort between the South Florida Water Management District (SFWMD), the United States Army Corps of Engineers (USACE), and the National Park Service’s (NPS) Vegetation Mapping Inventory Program (VMI). The goal of this project is to produce a spatially and thematically accurate vegetation map of Everglades National Park and Big Cypress National Preserve prior to the completion of restoration efforts associated with CERP. This spatial product will serve as a record of baseline vegetation conditions for the purpose of: (1) documenting changes to the spatial extent, pattern, and proportion of plant communities within these two federally-managed units as they respond to hydrologic modifications resulting from the implementation of the CERP; and (2) providing vegetation and land-cover information to NPS park managers and scientists for use in park management, resource management, research, and monitoring. This mapping project covers an area of approximately 7,400 square kilometers (1.84 million acres [ac]) and consists of seven mapping regions: four regions in Everglades National Park, Regions 1–4, and three in Big Cypress National Preserve, Regions 5–7. The report focuses on the mapping effort associated with the Northwest Coastal Everglades (NWCE), Region 4 , in Everglades National Park. The NWCE encompasses a total area of 1,278 square kilometers (493.7 square miles [sq mi], or 315,955 ac) and is geographically located to the south of Big Cypress National Preserve, west of Shark River Slough (Region 1), and north of the Southwest Coastal Everglades (Region 3). Photo-interpretation was performed by superimposing a 50 × 50-meter (164 × 164-feet [ft] or 0.25 hectare [0.61 ac]) grid cell vector matrix over stereoscopic, 30 centimeters (11.8 inches) spatial resolution, color-infrared aerial imagery on a digital photogrammetric workstation. Photo-interpreters identified the dominant community in each cell by applying majority-rule algorithms, recognizing community-specific spectral signatures, and referencing an extensive ground-truth database. The dominant vegetation community within each grid cell was classified using a hierarchical classification system developed specifically for this project. Additionally, photo-interpreters categorized the absolute cover of cattail (Typha sp.) and any invasive species detected as either: Sparse (10–49%), Dominant (50–89%), or Monotypic (90–100%). A total of 178 thematic classes were used to map the NWCE. The most common vegetation classes are Mixed Mangrove Forest-Mixed and Transitional Bayhead Shrubland. These two communities accounted for about 10%, each, of the mapping area. Other notable classes include Short Sawgrass Marsh-Dense (8.1% of the map area), Mixed Graminoid Freshwater Marsh (4.7% of the map area), and Black Mangrove Forest (4.5% of the map area). The NWCE vegetation map has a thematic class accuracy of 88.4% with a lower 90th Percentile Confidence Interval of 84.5%.

Bingham, Sonia, and Craig Young. Sentinel wetlands in Cuyahoga Valley National Park: I. Ecological characterization and management insights, 2008–2018. Edited by Tani Hubbard. National Park Service, February 2023. http://dx.doi.org/10.36967/2296885.

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Sentinel wetlands at Cuyahoga Valley National Park (NP) comprise a set of twenty important management areas and reference sites. These wetlands are monitored more closely than other wetlands in the wetlands monitoring program and are the focus of the volunteer monitoring program for water levels. We used the Ohio Rapid Assessment Method (ORAM) to evaluate habitat in the sentinel wetlands. A total of 37 long-term sample plots have been established within these wetlands to monitor biological condition over time using vegetation as an indicator. Vegetation is intensively surveyed using the Vegetation Index of Biotic Integrity (VIBI), where all plant species within the plot are identiﬁed to the lowest taxonomic level possible (genus or species). Sample plots were surveyed twice from 2008 to 2018 and the vegetation data were evaluated using ﬁve metrics: VIBI, Floristic Quality Assessment Index (FQAI), percent sensitive plant species, percent invasive graminoids, and species richness. These metrics are discussed for each location. This report also highlights relevant land use histories, common native plant species, and invasive species of concern at each wetland. This is the ﬁrst report in a two-part series, designed to summarize the results from intensive vegetation surveys completed at sentinel wetlands in 2008–2018. Boston Mills, Virginia Kendall Lake, Stumpy Basin, Columbia, and Beaver Marsh are all in excellent condition at one or more plots. They have unique habitats with some specialized plant species. Fawn Pond is in good condition at most plots and scores very high in comparison to other wetlands within the riverine mainstem hydrogeomorphic class. Metric scores across mitigation wetlands were low. Two of the three wetlands (Brookside and Rockside) are not meeting the benchmarks originally established by the United States Army Corps of Engineers and Ohio Environmental Protection Agency. Krejci is still a young mitigation site and success will be determined over time. Park-supported invasive species control eﬀorts will be crucial for long-term success of these sites and future mitigation/restoration projects. The wetlands monitored because of proposed ecological restoration projects (Pleasant Valley, Stanford, and Fawn Pond) have extensive invasive plant communities. These restoration sites should be re-evaluated for their feasibility and potential success and given an order of prioritization relative to the newer list of restoration sites. Cuyahoga Valley NP has added many new areas to their list of potential wetland restoration sites after these areas were selected, and there may be better opportunities available based on restoration objectives. Restoration goals should be based on the park's desired future conditions, and mitigation goals of outside partners may not always be in line with those. The multiple VIBI plots dispersed throughout the large wetlands at Cuyahoga Valley NP detected and illuminated spatial patterns in condition. Many individual wetlands had a wide range of VIBI scores within their boundaries, sometimes reﬂecting localized disturbances, past modiﬁcations, and management actions. Most often, these large ﬂuctuations in condition were linked to local invasive plant infestations. These infestations appear to be the most obvious and widespread threat to wetland ecosystems within the park, but also the most controllable threat. Some sensitive species are still present in some of the lowest scoring plots, which indicates that invasive plant species control eﬀorts may pay oﬀ immediately with a resurgence of native communities. Invasive plant control at rare habitat sites would have large payoﬀs over time by protecting some of the park's most unique wetlands. Reference wetlands would also be good demonstration sites for park managers to try to maintain exemplary conditions through active management. Through this work, park managers can evaluate the feasibility, eﬀectiveness, and scalability of management practices required to maintain wetland condition.

Struthers, Kim. Natural resource conditions at Fort Pulaski National Monument: Findings and management considerations for selected resources. National Park Service, December 2023. http://dx.doi.org/10.36967/2300064.

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The National Park Service (NPS) Water Resources Division’s Natural Resource Condition Assessment (NRCA) Program initiated an NRCA project with Fort Pulaski National Monument (FOPU) in 2022. The purpose of an NRCA is to synthesize information related to the primary drivers and stressors affecting natural resource conditions at a park and to report conditions for natural resource topics selected by park managers. Resource conditions are evaluated as either a condition assessment or a gap analysis, depending on data availability. For FOPU’s NRCA, managers selected salt marsh, shorebirds, Eastern oyster (Crassostrea virginica), and butterflies as the focal resources. FOPU is comprised of two islands in coastal Georgia, McQueens and Cockspur, which are separated by the Savannah River near its confluence with the Atlantic Ocean. Cockspur Island contains the 19th century masonry fort, Fort Pulaski, and the monument’s visitor services and facilities and is primarily constructed with dredge material from the Savannah River. McQueens Island is almost entirely salt marsh habitat and most of its area is eligible federal wilderness, containing one of Georgia’s oyster recreational harvest areas (RHAs), Oyster Creek RHA. Both McQueens and Cockspur islands are designated as a National Oceanic and Atmospheric Administration Marine Protected Area (MPA), underscoring FOPU’s natural resource significance. Riverine, freshwater, and estuarine wetlands cover 83.81% of FOPU, with the latter accounting for almost 99% of all monument wetlands. Persistently emergent vegetation of smooth cordgrasses (Spartina spp.) and unconsolidated shore represent the dominant wetland types. McQueens Island estuarine wetlands were evaluated for 11 functions and were rated primarily as high functioning, except for the wetland north of Highway 80, where the causeway has altered its ability to function properly. The wetland west of the Highway 80 bend is composed of unconsolidated material so was rated as moderately functioning in carbon sequestration, retention of sediments, and shore stabilization. In contrast, the unconsolidated shore wetland in the Oyster Creek RHA, where the highest concentration of FOPU’s oysters occurs, were rated high for all expected wetland functions. In 2013, over 75% of the total oyster area from within four of Georgia’s RHAs was in the Oyster Creek RHA. A spectral analysis of oyster density in Oyster Creek RHA, comparing 2013 and 2018 images, reported an increase in the high-density class, a decrease in the moderate-low class, and an increase in the no oyster class, with the latter likely a function of how oyster areas were drawn between the images. A successful 2013 enhanced reef project in Oyster Creek RHA reported a pre-enhancement oyster area of 2.68 m2 (28.8 ft2) that increased to 894.2 m2 (0.22 ac) of oysters by 2018. FOPU’s extensive salt marsh habitat and beaches provide critical food sources and habitat for shorebirds in the Atlantic Flyway, especially during the pre-breeding season. The American Oystercatcher (Haematopus palliates), Whimbrel (Numenius phaeopus), and the federally threatened rufa subspecies of Red Knot (Calidris canutus rufa) are identified as high priority species in the flyway and have been observed on Cockspur Island during the Manomet International Shorebird Surveys (2019–2022) at FOPU. The USFWS (2023) is seeking additional critical habitat designation, which will include Cockspur Island, for the rufa subspecies of Red Knot, whose estimated population abundance trend is declining throughout its entire range. FOPU’s non-wetland, upland habitat is primarily located on Cockspur Island and supports vegetation that can serve as host, roost and/or nectar plants for pollinators, especially butterflies. Cedar–Live Oak–Cabbage Palmetto (Juniperus virginiana var. silicicola–Q. virginiana–Sabal palmetto) Marsh Hammock and Cabbage Palmetto Woodland contain the most diversity of beneficial butterfly plants. While a comprehensive butterfly inventory is needed, fall migration surveys have recorded three target species of the Butterflies of the Atlantic Flyway (BAFA): monarch (Danaus plexippus), gulf fritillary (Agraulis vanillae), and cloudless sulphur (Phoebis sennae). Collectively, FOPU’s natural resources are affected by the sea level, which has risen by 0.35 m (1.15 ft) from 1935 to 2022. Hardened shorelines, such as causeways or armored structures, are identified as the greatest threat to the salt marsh habitat’s ability to migrate upland with continued sea level rise. Erosion along Cockspur Island’s north shore is an ongoing issue and FOPU managers have been working with the U.S. Army Corps of Engineers to develop solutions to address the erosion, while also creating habitat for shorebirds. Several agencies routinely monitor for water and sediment pollution in and around FOPU, which, if managed collectively, can inform landscape-level management actions to address drivers that are influencing resource conditions at the ecosystem level.