Relevant bibliographies by topics / Shell Group

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Academic literature on the topic 'Shell Group'

Author: Grafiati
Published: 4 June 2021
Last updated: 9 February 2022

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Journal articles on the topic "Shell Group"

1

Ma, Xueping, and Jed Day. "Revision of selected North American and Eurasian Late Devonian (Frasnian) species of Cyrtospirifer and Regelia (Brachiopoda)." Journal of Paleontology 77, no. 2 (March 2003): 267–92. http://dx.doi.org/10.1017/s0022336000043638.

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Study of the shell features of Givetian and Frasnian spiriferid brachiopods attributed to the genus Cyrtospirifer shows that the type species C. verneuili has micro-ornament consisting of fine concentric growth lines, radial capillae, with microspines arising from some capillae, spine bases appear to extend into the primary shell layer. Its dorsal interior features a pseudoseptum supporting the cardinalia. Micro-ornament of Cyrtospirifer varies widely and is a useful criterion for characterization of species of the genus. Most Frasnian species retained in the genus have micropustulate shells. Two late Givetian and Frasnian phylogenetic species groups of Cyrtospirifer are recognized based on similarities of shell form and external and internal shell features. Species of the verneuilisyringothyriformis group have transverse alate shells, and are the most abundant and widespread group in Frasnian deposits worldwide. The verneuiliformis group includes the oldest known species of Cyrtospirifer with narrow hinges and more inflated ventral valves where shell width is close to or equal to length. The oldest Cyrtospirifer originated in western Europe during the late Givetian, and subsequently migrated at different times during the Frasnian into other shelf areas of Eurasia, North America and China. The initial migration of Cyrtospirifer into tropical and subtropical shelf settings in North America coincided with the middle Frasnian eustatic sea level rise of Devonian Transgressive-Regressive (T-R) cycle IIc of Johnson and others. A second late Frasnian dispersal from western Canada to subtropical carbonate and clastic shelves in the southwestern and central U.S. coincided with the initial sea level rise of T-R cycle IId of Johnson and others. The Frasnian species Cyrtospirifer glaucus Crickmay, 1952a (middle Frasnian of western Canada) is the type species for Regelia Crickmay, 1952b, and is considered a valid genus, and is not a synonym of C. chemungensis (Conrad, 1842) as previously interpreted by some authors. Regelia differs from Cyrtospirifer in the absence of a delthyrial plate, complete in-filling of the delthyrial cavity by secondary shell material, its simpler rod-like teeth, and its fewer medial sinal shell plications. Species of Regelia are restricted to the middle to late Frasnian of North America.
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Chu, You-Hua. "Multiple Shell Planetary Nebulae." Symposium - International Astronomical Union 131 (1989): 105–16. http://dx.doi.org/10.1017/s0074180900137696.

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It has been shown in several independent investigations that the multiple-shell phenomenon is prevalent in planetary nebulae. Despite the common classification, the multiple shell planetary nebulae are a heterogeneous group of objects, as testified by the wide variety of their morphologies and physical structures. There are two types of double-shell structures that are seen frequently: one has an inner shell expanding supersonically into a faint, subsonically expanding halo, and the other has a bright attached envelope co-expanding with the inner shell. The physical structures and relative elemental abundances in the shells are reviewed, and their possible formation mechanisms are discussed.
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Buddawong, Tiranan, Somluk Asuvapongpatana, Chanyatip Suwannasing, Valainipha Habuddha, Chompoonut Sukonset, Chanyarak Sombutkayasith, Carmel McDougall, and Wattana Weerachatyanukul. "Calcineurin subunit B is involved in shell regeneration in Haliotis diversicolor." PeerJ 9 (January 12, 2021): e10662. http://dx.doi.org/10.7717/peerj.10662.

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Abalone shells are mainly composed of two major polymorphs of CaCO3 that are distributed in different layers of the shell. The process of shell biomineralization is controlled by genes and proteins expressed within the mantle epithelium. In this present paper, we conducted a shell regeneration experiment to study the role of HcCNA and HcCNB (individual subunits of calcineurin) in shell biomineralization in H. diversicolor. The results of qPCR showed that HcCNB is upregulated to a greater extent than HcCNA in the mantle after shell notching. In vivo study of the effects of rHcCNB injection showed a significantly higher percentage of regenerated shell length, but not area, in the injected group compared to the control group. In addition, SEM observation of the inner surface of the regenerated shells revealed three different zones including prismatic, nacreous, and a distinct transition zone. Changes in the crystal organization and ultrastructure are clearly evident in these three zones, particularly after 3 weeks of rHcCNB administration. We hypothesize that this is due to faster biomineralization rates in the rHcCNB treated group. Taken together, our results demonstrate that HcCNB participates in shell regeneration in H. diversicolor. As calcineurin subunits have also been implicated in shell formation in bivalves, these findings suggest that calcineurin subunits may play important roles in biomineralization in all conchiferans.
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Kutzner, M., C. Tidwell, S. E. Vance, and V. Radojević. "Inner-shell photoionization of group-IIBatoms." Physical Review A 49, no. 1 (January 1, 1994): 300–309. http://dx.doi.org/10.1103/physreva.49.300.

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Davies, David J., and Molly F. Miller. "Paleocommunity information retrieval vs. shell accumulation mode in Paleozoic carbonates: examples from the Lebanon Limestone (Middle Ordovician), Tennessee, U.S.A." Paleontological Society Special Publications 6 (1992): 81. http://dx.doi.org/10.1017/s2475262200006419.

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Compared to their terrigenous counterparts, carbonate shell accumulations have until recently been relatively little studied to determine either descriptive or genetic classifications of shell bed types, the preservation potential of each type, or their relative ability to preserve community-level information. A partial classification of Paleozoic carbonate shell-rich soft sediment accumulations is proposed using sedimentation patterns in the Lebanon limestone of the Stones River Group. Paleoecological information preserved therein is then contrasted by shell bed type. The Lebanon represents typical Ordovician shallow to moderate subtidal carbonate shelf deposits in outcrops flanking the Nashville Dome and peritidal deposits in the Sequatchie Anticline of Eastern Tennessee; shell beds alternate with shell poor sediments (micrites, wackestones and diagenetically enhanced dolomites and clay-rich partings).None of the analyzed shell beds was strictly biological in origin; most are sedimentological although >10% are combined sedimentological/diagenetic. While the majority are single simple shell beds, >20% are amalgamated. All are thin (1 shell to 15 cm) stringers that pinch and swell showing poor lateral continuity (outcrop scale, tens to hundreds of meters) likely enhanced by burial dissolution. These shell beds differ greatly in fabric (packing/sorting), clast composition, taphonomic signature, and intensity of time averaging; thus community information retrieval is biased in predictable patterns. Virtually no shell beds show common shell dissolution or encrustation from long-term sediment surface exposure or hardground formation. Five major categories of accumulation are herein proposed using a DESCRIPTIVE, non-genetic terminology modified from previous works of DJD, as well as a Genetic interpretation for each. These are easily distinguished in the field and are also discriminated by Q-mode cluster analysis.Categories include, in decreasing frequency of occurrence: 1. SHELL GRAVELS; Storm/“event” beds: Sharp bases; poorly sorted coarse basal bioclasts and/or intraclasts, often with no preferred orientation; clasts fine upward to comminuted shell material and micrite. Horizontal platy brachiopods often cap the beds. High diversity and a wide range in shell alteration is represented, from whole unaltered brachiopods to minor abraded fragments, indicating extreme time averaging and poor resolution of short-term community dynamics. 2. COMMINUTED SHELLY LS; Current/ripple concentrations: Small tidal channel fill and discrete ripple trough accumulations are composed of cross-stratified bioclastic deposits with local concentrations of rip-ups. Beds are not graded; typically clasts are abraded, rounded and concordant with cross-beds. Intense time averaging and mixing of discrete communities is inferred due to continual reworking in these background deposits. 3. SHELL/CEMENT LS; Early cementation beds: Intense early diagenetic alteration is inferred due to red discoloration and rapid intergranular cementation; some beds show diagenetic micritic rinds. Beds may be brecciated and show deep burial stylolitization cutting bioclasts and cement. They may represent zones of preferred early cementation rather than a change in shell accumulation rate. Many shells from some beds show little postmortem alteration; these units may preserve much of the original community structure. 4. DENSE SHELL PAVEMENTS; Subtidal surficial pavements: Single layers of shells, commonly concave down, overlie mudstones/wackestones with no basal erosion. No obrution deposits were noted. Bioclasts are typically disarticulated and reoriented, but are not substantially abraded, broken, or dissolved. Diversity is low. Only minor temporal and lateral community mixing with small environmental fluctuation is indicated. 5. VERTICALLY IMBRICATE SHELLY LS; High energy beach zones: Platy whole and major fragments of brachiopods are deposited in low diversity, high angle imbricate beds. Less postmortem reworking and time averaging is evident compared to types 1 and 2.Thus, the most common (physically reworked) shell bed types show the most intense loss of short-term paleocommunity information. There are surprisingly few insitu community pavements or obligate long-term accumulations. This pattern differs from some described Ordovician carbonates, which may contain common community beds or hardgrounds/hiatal accumulations. This implies a relatively low rate of net sediment accumulation on a shallow, periodically wave swept shelf, and no major flooding surfaces or other indications of significant sea level change. Delineation of the sequence stratigraphic position of these carbonates is enhanced from this type of integrated community/biostratinomic analysis.
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Jiménez-Berrocoso, Álvaro, Eduardo B. Olivero, and Javier Elorza. "New petrographic and geochemical insights on diagenesis and palaeoenvironmental stress in Late Cretaceous inoceramid shells from the James Ross Basin, Antarctica." Antarctic Science 18, no. 3 (August 24, 2006): 357–76. http://dx.doi.org/10.1017/s0954102006000411.

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New petrographic and geochemical insights from inoceramid bivalve shells of lower Campanian (Marambio Group, James Ross Basin, Antarctica) show that they suffered significant palaeoenvironmental stress just before their disappearance in the southern high latitudes. Inoceramid data have mainly been derived from shell fragments of the large form Antarcticeramus rabotensis Crame & Luther, collected at stratigraphical levels marking the early disappearance of inoceramids in the James Ross Basin (10 m.y. before the Cretaceous/Tertiary boundary in Antarctica). Cathodoluminescence studies and minor and trace element intra-shell variations in A. rabotensis shells, along with their whole shell geochemistry (major, minor, and trace elements, including REE), have revealed evidence of only weak diagenesis but significant palaeoenvironmental stress. The most relevant evidence of such adverse palaeoenvironmental conditions in A. rabotensis shells is reflected by marked growth interruptions in the normal shell layering, including the occurrence of a previously undetected inner aragonitic nacreous layer formed of alternating aragonitic and calcitic sublayers. The weak diagenesis produced characteristic geochemical intra-shell variations, which have subsequently been detected in the inoceramid shell microstructure, especially in the inner aragonitic nacreous layer.
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Butler, Aodhán D., Michael Streng, Lars E. Holmer, and Loren E. Babcock. "Exceptionally preserved Mickwitzia from the Indian Springs Lagerstätte (Cambrian Stage 3), Nevada." Journal of Paleontology 89, no. 6 (November 2015): 933–55. http://dx.doi.org/10.1017/jpa.2016.8.

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AbstractExceptionally preserved specimens of the Cambrian stem-group brachiopod Mickwitzia occidens Walcott, 1908 are described in detail from the Indian Springs Lagerstätte in Nevada, USA. Shell structure and preserved mantle setae from these specimens reveal a variable diagenetic (taphonomic) history and provide insight into the phylogenetic position of mickwitziids. Morphologic and morphometric comparison to M. monilifera (Linnarsson, 1869) from Sweden and M. muralensis Walcott, 1913 from British Columbia, Canada reveals clear species-level distinctions. Scanning electron microscopic analysis allows revision of the generic diagnosis. The Mickwitzia shell is characterized by the presence of inwardly pointing phosphatic cones and tangential setae-bearing tubes. The inwardly pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent endopunctae-like structures. Acrotretid-like shell structures and shell-penetrating setae in M. occidens strengthen the previously proposed close relationship between stem-group brachiopods and tommotiids, a group of small shelly fossils.
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Qian, Li Peng, Du Yuan, Guang Shun Yi, and Gan Moog Chow. "Critical shell thickness and emission enhancement of NaYF4:Yb,Er/NaYF4/silica core/shell/shell nanoparticles." Journal of Materials Research 24, no. 12 (December 2009): 3559–68. http://dx.doi.org/10.1557/jmr.2009.0432.

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Amorphous silica shells, used for functionalization of inorganic nanoparticles in bioapplications, were coated on chemically synthesized NaYF4:Yb,Er upconversion fluorescent nanoparticles via a reverse microemulsion method by using dual surfactants of polyoxyethylene (5) nonylphenylether and 1-hexanol, and tetraethyl orthosilicate as precursor. NaYF4:Yb,Er nanoparticles were equiaxed with a particle size of 11.1 ± 1.3 nm. The thickness of silica shell was ∼8 nm. NaYF4:Yb,Er/silica core/shell nanoparticles were well dispersed in solvents such as ethanol and deionized water. The emission intensities of NaYF4:Yb,Er/silica core/shell nanoparticles remained the same as that of uncoated nanoparticles after surface functionalization with an amine group using (3-aminopropyl)-trimethoxysilan. Silica, although providing a good barrier to the nonradiative relaxation between the upconversion nanoparticles and the environments, did not enhance the emission intensity of upconversion nanoparticles. To increase the emission intensity of NaYF4:Yb,Er/silica core/shell nanoparticles, an undoped NaYF4 shell (∼3-nm thick) was deposited on the upconversion nanoparticles before the silica coating. The total emission intensity of NaYF4:Yb,Er/NaYF4/silica core/shell/shell nanoparticles increased by 15 times compared to that without the intermediate NaYF4 shell. The critical shell thickness of NaYF4 was ∼3 nm, beyond which no further emission intensity enhancement was observed.
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Kehrwald, Natalie M., William D. McCoy, Jeanne Thibeault, Stephen J. Burns, and Eric A. Oches. "Paleoclimatic implications of the spatial patterns of modern and LGM European land-snail shell δ18O." Quaternary Research 74, no. 1 (July 2010): 166–76. http://dx.doi.org/10.1016/j.yqres.2010.03.001.

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AbstractThe oxygen isotopic composition of land-snail shells may provide insight into the source region and trajectory of precipitation. Last glacial maximum (LGM) gastropod shells were sampled from loess from Belgium to Serbia and modern land-snail shells both record δ18O values between 0‰ and − 5‰. There are significant differences in mean fossil shell δ18O between sites but not among genera at a single location. Therefore, we group δ18O values from different genera together to map the spatial distribution of δ18O in shell carbonate. Shell δ18O values reflect the spatial variation in the isotopic composition of precipitation and incorporate the snails' preferential sampling of precipitation during the warm season. Modern shell δ18O decreases in Europe along a N–S gradient from the North Sea inland toward the Alps. Modern observed data of isotopes in precipitation (GNIP) demonstrate a similar trend for low-altitude sites. LGM shell δ18O data show a different gradient with δ18O declining toward the ENE, implying a mid-Atlantic source due to increased sea ice and a possible southern displacement of the westerly jet stream. Balkan LGM samples show the influence of a Mediterranean source, with δ18O values decreasing northward.
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Mudaim, Sarifah, Sahrul Hidayat, and Risdiana. "Effect of Heating Temperature on the Chemical Structure and of Conductivity Carbon from Candlenut Shells (Aleurites Moluccana)." Materials Science Forum 1028 (April 2021): 302–7. http://dx.doi.org/10.4028/www.scientific.net/msf.1028.302.

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Candlenut Shells is one of the many commodities growing in Indonesia and experiencing rapid progress production development. The shell of candlenut has good characteristic that allow it to be used as carbon. activated carbon is one of material that can be applied for various application. In this paper, we reported the synthesis of activated carbon from candlenut shell in order to get high quality of carbon by controlling the heating temperature in synthesis. Variation of heating temperature in to produce carbon were 300, 400, 500, 600 and 700 °C . FTIR Spectroscopy was carried out to determine the functional groups on the carbon from candlenut shells. FTIR analysis during the carbonization process was indicated the change in functional group of chemical structure from the candlenut shell, which is shown by decreasing the absorption spectrum of some functional groups of the candlenut shell after the carbonization process. The carbonization process has formed aromatic C = C and reduction functional group OH (aromatic compounds), C-H (aromatic ring), C-O (vibration ether structure) dan C=O (Ester compounds). And results of carbonization of candlenut shells at various temperatures have an electrical conductivity value that increases with increasing carbonization temperature. The carbonization temperature that is raised to 700 °C causes carbon to be more conductive with an increased electrical conductivity value. XRF characterization results also showed that in addition to carbon elements in the cundlenut shells, other elements were also found such as calcium, magnesium, aluminum, potassium, strontium, manganese, iron and zinc. Ca and Mg are the largest content besides carbon.
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Dissertations / Theses on the topic "Shell Group"

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Ho, Yanfang. "Group theoretical analysis of in-shell interaction in atoms." Scholarly Commons, 1985. https://scholarlycommons.pacific.edu/uop_etds/487.

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A group theoretic approach to Layzer's 1/2 expansion method is explored. In part this builds on earlier work of Wulfman(2), of Moshinsky et al(l4), and of Sinanoglu, Herrick(lS), and Kellman (16) on second row atoms. I investigate atoms with electrons in the 3s-3p-3d shell and find: 1. Wulfman's constant of motion accurately predicts configuration mixing for systems with two to eight electrons in the 3s-3p subshell. 2. The same constant of motion accurately predicts configuration mixing for systems with two electrons in the 3s-3p-3d shell. 3. It accurately predicts configuration mixing in systems of high angular momentum L and of high spin angular momentum S containing three electrons in the 3s-3p-3d shell, but gives less accurate results when L and S are both small. I also show how effective nuclear charges may be calculated by a group theoretical approach. In addition I explore several new methods for expressing electron repulsion operators in terms of operators of the 80(4,2) dynamical group of one - electron atoms.
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Holzer, Boris. "Transnational subpolitics and corporate discourse : a study of environmental protest and the Royal Dutch/Shell Group." Thesis, London School of Economics and Political Science (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393577.

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Katona, Gregory. "Field Theoretic Lagrangian From Off-Shell Supermultiplet Gauge Quotients." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5958.

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Recent efforts to classify off-shell representations of supersymmetry without a central charge have focused upon directed, supermultiplet graphs of hypercubic topology known as Adinkras. These encodings of Super Poincare algebras, depict every generator of a chosen supersymmetry as a node-pair transformtion between fermionic / bosonic component fields. This research thesis is a culmination of investigating novel diagrammatic sums of gauge quotients by supersymmetric images of other Adinkras, and the correlated building of field theoretic worldline Lagrangians to accommodate both classical and quantum venues. We find Ref [40], that such gauge quotients do not yield other stand alone or ”proper” Adinkras as afore sighted, nor can they be decomposed into supermultiplet sums, but are rather a connected ”Adinkraic network”. Their iteration, analogous to Weyl's construction for producing all finite-dimensional unitary representations in Lie algebras, sets off chains of algebraic paradigms in discrete-graph and continuous-field variables, the links of which feature distinct, supersymmetric Lagrangian templates. Collectively, these Adiankraic series air new symbolic genera for equation to phase moments in Feynman path integrals. Guided in this light, we proceed by constructing Lagrangians actions for the N = 3 supermultiplet YI /(iDI X) for I = 1, 2, 3, where YI and X are standard, Salam-Strathdee superfields: YI fermionic and X bosonic. The system, bilinear in the component fields exhibits a total of thirteen free parameters, seven of which specify Zeeman-like coupling to external background (magnetic) fluxes. All but special subsets of this parameter space describe aperiodic oscillatory responses, some of which are found to be surprisingly controlled by the golden ratio, ? ? 1.61803, Ref [52]. It is further determined that these Lagrangians allow an N = 3 ? 4 supersymmetric extension to the Chiral-Chiral and Chiral-twisted- Chiral multiplet, while a subset admits two inequivalent such extensions. In a natural progression, a continuum of observably and usefully inequivalent, finite-dimensional off-shell representations of worldline N = 4 extended supersymmetry are explored, that are variate from one another but in the value of a tuning parameter, Ref [53]. Their dynamics turns out to be nontrivial already when restricting to just bilinear Lagrangians. In particular, we find a 34-parameter family of bilinear Lagrangians that couple two differently tuned supermultiplets to each other and to external magnetic fluxes, where the explicit parameter dependence is unremovable by any field redefinition and is therefore observable. This offers the evaluation of X-phase sensitive, off-shell path integrals with promising correlations to group product decompositions and to deriving source emergences of higher-order background flux-forms on 2-dimensional manifolds, the stacks of which comprise space-time volumes. Application to nonlinear sigma models would naturally follow, having potential use in M- and F- string theories.
Ph.D.
Doctorate
Physics
Sciences
Physics
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McKechnie, Iain. "Five thousand years of fishing at a shell midden in the broken group islands, Barkley Sound, British Columbia /." Burnaby B.C. : Simon Fraser University, 2005. http://ir.lib.sfu.ca/handle/1892/2170.

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Scheibel, Markus. "Metal-Nitrogen Multiple Bonds with Square-Planar Group 9 Transition Metal PNP Pincer Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9944-4.

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Srinivasan, Jagannathan. "Sensing animal group behavior and bio-clutter in the ocean over continental shelf scales." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67587.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 267-294).
Fish populations often comprise the largest biomass in a productive marine ecosystem. They typically play an essential role in inter-trophic energy transport, and serve as a mainstay for human consumption comprising roughly 16% of the animal protein consumed by the world's population. Despite their ecological importance, there is substantial evidence that fish populations are declining worldwide, motivating the need for an ecosystem approach to fisheries management through ecosystem scale sensing of fish populations and behavior. In this Thesis, it is shown how the recently developed Ocean Acoustic Waveguide Remote Sensing (OAWRS) technique can be used to (1) quantify the acoustic scattering response of fish and remotely infer their physiological characteristics to enable species classification, and (2) remotely assess shoaling populations and quantify their group behavior in a variety of oceanic ecosystems. Shoal dynamics is studied by developing a novel Minimum Energy Flow (MEF) method to extract velocity and force fields driving motion from time-varying density images describing compressible or incompressible motion. The MEF method is applied to experimentally obtained density images, spanning spatial scales from micrometers to several kilometers. Using density image sequences describing cell splitting, for example, we show that cell division is driven by gradients in apparent pressure within a cell. By applying MEF to fish population density image sequences collected during the OAWRS 2003 experiment in the New Jersey strataform, we quantify (1) inter-shoal dynamics such as coalescence of fish groups over tens of kilometers, (2) fish mass flow between different parts of a large shoal and (3) the stresses acting on large fish shoals. Observations of fish shoals made during the OAWRS 2006 experiment in the Georges Bank are used to confirm general theoretical predictions on group behavior believed to apply in nature irrespective of animal species. By quantifying the formation processes of vast oceanic fish shoals during spawning, it is shown that (1) a rapid transition from disordered to highly synchronized behavior occurs as population density reaches a critical value; (2) organized group migration occurs after this transition; and (3) small sets of leaders significantly influence the actions of much larger groups. Several species of fish, birds, insects, mammals and other self propelled particles (SPPs) are known to group in large numbers and exhibit orderly migrations. The stability of this orderly state of motion in large SPP-groups is studied by developing a fluid-dynamic theory for flocking behavior based on perturbation analysis. It is shown that an SPP group where individuals assume the average velocity of their neighbours behaves as a fluid over large spatial scales. The existence of a critical population density above which perturbations to the orderly state of motion are damped is also shown. Further, it is shown that disturbances can propagate within mobile groups at speeds much higher than that of the individuals, facilitating rapid information transfer. These findings may explain how large shoals of fish and flocks of birds are able to stay together and migrate over large distances without breaking up. Fish shoals are ubiquitous in continental shelf environments and so are a major cause of acoustic clutter in long-range Navy sonars. It is shown that man-made airfilled cylindrical targets have very different spectral acousic scattering response than fish, so that they can be distinguished using multi-frequency measurements. It is also shown that the use of the Sonar Equation to model scattering from the man-made targets leads to large errors differing by up to an order of magnitude from measurements. A Greens' Theorem-based full-field model that describes scattering from vertically extended cylindrical targets in range-dependent ocean waveguides is shown to accurately describe the statistics of the targets' scattered field measured during OAWRS 2001, 2003 and 2006 experiments. Measurements of infrasound made during the 2004 Indian Ocean Tsunami event that occured on December 26, 2004 have suggested that large-scale tsunamis may produce deep-infrasonic signals that travel thousands of kilometers in the atmosphere. By developing an analytical model to describe air-borne infrasound generation by tsunamis and applying it to the 2004 Indian Ocean Tsunami, it is shown that the mass flow of air caused by changes in sea-level due to a tsunami can generate infrasound of sufficient amplitude to be picked up thousands of kilometers away. The possibility of detecting tsunamis via seismic means is also examined by developing an analytical model for quantifying very low frequency (0.01-0.1 Hz) Rayleigh waves generated by a tsunami.
by Srinivasan Jagannathan.
Ph.D.
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7

Yi, Dong Hoon. "Investigating group behavioral quantization of oceanic fish with Continental-shelf scale ocean-acoustic sensing." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115671.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 177-194).
The recent fish population decline due to increased human presence has led to calls for predictive methods to help reverse or stabilize the situation. It has been difficult, however, to establish such methods primarily due to the technical obstacles in observing fish populations in natural habitats. Here we use acoustics to observe the ocean environment and study fish behavior during the critical spawning period over continental-shelf scales. Fish are known to be one of the main sources of strong natural returns in the continental-shelf environment, and so identified as a major source of clutter for wide-area undersea surveillance. The first continental-shelf scale acoustic measurements of Atlantic cod over thousands of square kilometers using towed source and receiver arrays were made by an international, multi-disciplinary team led by MIT researchers including myself in the historic Lofoten cod spawning ground in Norway during the peak spawning period in Winter 2014, where extensive but spatially discrete groups of spawning cod were successfully imaged. These initial instantaneous wide-area observations of cod aggregations suggest that these observed spawning groups have quantifiable properties that are linked to essential collective behavioral functions. We find that the mean group population per annual spawning season of Northeast Arctic cod over the entire spawning ground in Lofoten Norway is remarkably invariant across the available 30 years of line-transect survey data. The marked stability of the annual mean spawning group size in contrast to the large variations in total spawning population across years supports the interpretation of the expected spawning group size over the 30-year data set as the group behavioral quantum empirically expected for reliable spawning. Time series of the total Atlantic cod spawning population for major spawning regions across the North Atlantic show that once the total spawning population declined below a quantum, recovery to preindustrial levels did not occur in that region even after decades, which is an apparent consequence of large difference between the pre-industrial level and one quantum level. Quantized group behavior during spawning is also investigated for the Atlantic herring species. We find that the daily herring spawning group population is stable over the peak annual spawning period from wide-area acoustic measurements of spawning herring in the Gulf of Maine in Fall 2006. This supports the quantum concept that the mean spawning group population has evolved to a stable optimal size to fulfill the essential behavioral function of reliable spawning for Atlantic herring. As with cod, time series of the Atlantic herring spawning population for major spawning grounds across the North Atlantic show that when total spawning population declined below the empirically determined quantum level, return to pre-industrial levels required decades. Our findings show that to be sustained at pre-industrial levels the total spawning population must greatly exceed the mean spawning group size found at pre-industrial levels for any oceanic fish population we investigated, and likely many others. The migration of extensive social groups towards specific spawning grounds in vast and diverse ocean environments is an integral part of the regular spawning process of many oceanic fish species. Oceanic fish in such migrations typically seek locations with environmental parameters that maximize the probability of successful spawning and egg/larval survival. The 3D spatio-temporal dynamics of these behavioral processes are largely unknown due to technical difficulties in sensing the ocean environment over wide areas. Here we use ocean acoustic waveguide remote sensing (OAWRS) to instantaneously image immense herring groups over continental-shelf-scale areas at the Georges Bank spawning ground. Via multi-spectral OAWRS measurements, we capture a shift in swimbladder resonance peak correlated with the herring groups' up-slope spawning migration, enabling 3D spatial behavioral dynamics to be instantaneously inferred over thousands of square kilometers. We show that herring groups maintain near-bottom vertical distributions with negative buoyancy throughout the migration. We find a spatial correlation greater than 0.9 between the average herring group depth and corresponding seafloor depth for migratory paths along the bathymetric gradient. This is consistent with herring groups maintaining near-seafloor paths to both search for optimal spawning conditions and reduce the risk of predator attacks during the migration to shallower waters where near-surface predators are more dangerous. This analysis shows that multi-spectral resonance sensing with OAWRS can be used as an effective tool to instantaneously image and continuously monitor the behavioral dynamics of swimbladder-bearing fish group behavior in 3 spatial dimensions over continental-shelf scales. Recent research has found a high spatial and temporal correlation between certain baleen whale vocalizations and peak annual spawning processes of Atlantic herring in the Gulf of Maine. These vocalizations are apparently related to feeding activities of baleen whales with suggested functions that include communication, prey manipulation, and echolocation. Here the feasibility of the echolocation function is investigated. Physical limitations on the ability to detect large herring shoals and the seafloor by acoustic remote sensing are determined with ocean acoustic propagation, scattering, and statistical theories given baleen whale auditory parameters. Detection is found to be highly dependent on ambient noise conditions, herring shoal distributions, baleen whale time-frequency vocalization spectra, and geophysical parameters of the ocean waveguide. Detections of large herring shoals are found to be physically feasible in common Gulf of Maine herring spawning scenarios at up to 10 ± 6 km in range for humpback parameters and 1 ± 1 km for minke parameters but not for blue and fin parameters even at zero horizontal range. Detections of the seafloor are found to be feasible up to 2 ± 1 km for blue and humpback parameters and roughly 1 km for fin and minke parameters, suggesting that the whales share a common acoustic sensation of rudimentary features of the geophysical environment. No effect of anthropogenic sound on marine mammal vocalization behavior was found during our measurements. Some published statistical tests assessing the impact of anthropogenic sound on marine mammal behavior were found to have 98-100% false positive biases with no true positive confirmation, and so lack statistical significance.
by Dong Hoon Yi.
Ph. D.
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Santoso, Binarko. "Petrology of permian coal, Vasse Shelf, Perth Basin, Western Australia." Curtin University of Technology, School of Applied Geology, 1994. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14920.

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The Early Permian coal samples for the study were obtained from the Vasse Shelf, southern Perth Basin, located approximately 200 km south- west of Perth. The selected coal samples for the study were also obtained from the Premier Sub-basin of the Collie Basin and the Irwin Sub-basin of the Perth Basin. The Early Permian coal measures are described as the Sue Coal Measures from the Vasse Shelf, the Ewington Coal Measures from the Premier Sub-basin and the coal measures from the Irwin sub-basin are described as the Irwin River Coal Measures.The Vasse Shelf coal is finely banded and the dominant lithotypes are dull and dull banded types, followed by bright banded and banded types, with minor bright types. The variation of dull and bright lithotypes represents fluctuating conditions of water table level during the growth of peat in the swamp. The maceral composition of the coal is predominantly composed of inertinite, followed by vitrinite and minor exinite and mineral matter. The coal is characterized by very low to medium semifusinite ratio and medium to high vitrinite content, supporting the deposition in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub- bituminous to high volatile bituminous of the Australian classification. In terms of microlithotype group, the predominance of inertite over vitrite suggests the coal was formed under drier conditions with high degree of oxidation during its deposition. On the basis of the interpretations of lithotypes, macerals, microlithotypes and trace elements, the depositional environment of the coal is braided and meandering deltaic-river system without any brackish or marine influence.The maceral composition of the Collie coal predominantly consists of inertinite and vitrinite, with low exinite and mineral matter. The very low to low semifusinite ratio and low to medium vitrinite content of ++
the coal indicate that the coal was formed under aerobic dry to wet conditions with some degree of oxidation. The coal is categorized as sub-bituminous according to the Australian classification. The domination of inertite and durite over vitrite and clarite contents in the coal reflects the deposition under drier conditions with fluctuations in the water table. On the basis of the interpretations of macerals, microlithotypes and trace elements distribution, the depositional environment of the coal is lacustrine, braided to meandering fluvial system, without the influence of any marine influx.The maceral composition of the Irwin River coal consists predominantly of vitrinite and inertinite, and minor exinite and mineral matter. The coal has very low semifusinite ratio and medium to high vitrinite content, suggesting the coal was deposited in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub-bituminous of the Australian classification. The predominance of vitrite and clarite over inertite and durite contents in the coal indicates that the coal was formed in wetter conditions and in high water covers with a low degree of oxidation. Based on macerals and microlithotypes contents, the depositional environment of the coal is braided fluvial to deltaic, which is in accordance with the interpreted non- marine and mixed marine environment of deposition in the sub-basin.The petrological comparisons of Vasse Shelf, Collie and Irwin River coals show that the average vitrinite content of the Irwin River coal is highest (49.1%) and of the Collie coal is lowest (37.3%) of the three. The inertinite content is highest in Collie coal (49.1%), followed by Vasse Shelf (46.4%) and Irwin River (39.2%) coals. The exinite content is low in Irwin River coal (6.3%) as compared with Vasse Shelf (9.0°/,) and Collie (8.3%) coals. The mineral matter content ++
is relatively low for all the three coals. The rank of the Vasse Shelf coal is high as compared with the Collie and Irwin River coals, either due to tectonic uplift after the deposition in post-Permian in the southern Perth Basin, or due to the average depth of burial over Vasse Shelf which is much greater than that of Collie and Irwin River coals.The comparisons of the coal from Western Australia with the selected Gondwana coals show that the predominance of inertinite over vitrinite occurs in the Western Australian coals (Vasse Shelf and Collie Basin). On the other hand, the Brazilian, eastern Australian, Indian and Western Australian (Irwin Sub-basin) coals are dominated by vitrinite over inertinite. The exinite content is highest in the Indian coals and lowest in the eastern Australian coals. The mineral matter content is highest in the Brazilian and Indian coals, and lowest in Western Australian (Vasse Shelf) and eastern Australian (Sydney Basin) coals. The rank of the coals ranges from sub- bituminous to medium volatile bituminous according to the Australian classification.
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Burley, Stuart Donald. "Diagenetic modelling in the Triassic Sherwood sandstone group of England and its offshore equivalents, United Kingdom continental shelf." Thesis, University of Hull, 1987. http://hydra.hull.ac.uk/resources/hull:3155.

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D’Amico, William P. "LEVERAGING GOVERNMENT AND COMMERCIAL INVESTMENTS." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608713.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
It is tempting to conceive a program that is self-contained and to fiscally control the all the necessary developments. Such a path will lead to a program that is technically stovepiped and extremely expensive. For the test and evaluation (T&E) community, products are often developed only for single application. We do not exist in such times. The use of other program’s products and commercial products is basically required. This is the path that the Hardened Subminiature Telemetry and Sensor System (HSTSS) has taken. The HSTSS philosophy required that the technologies common to telemetry systems be examined for reduction in cost, size, ease of use, and above all the survivability under high-g or high shock environments. It was clear that HSTSS could not support all of these requirements for transmitters, batteries, electronic packaging, and sensors and be realistically affordable with a good return on investment. This paper describes how the HSTSS program has accomplished the development of new batteries, transmitters, and data acquisition devices based upon a leveraged acquisition strategy.
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Books on the topic "Shell Group"

1

Kenny, Stephen M. H. Strategic options for information technology in the Shell group. Manchester: UMIST, 1997.

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Jennings, J. S. The role of business in environmental protection: An address to the third meeting of the China Council for International Cooperation on Environment and Development .... London: Shell International Petroleum Company, 1994.

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Moody-Stuart, Mark. Environmental action- a shared responsibility: An address to 'Building global partnerships', the second international conference on health, safety and the environment in oil and gas exploration .... London: Shell International Petroleum Company, 1994.

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Winged Shell: Oil company aviators 1927-1987. Penzance: Alison Hodge, 1987.

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Szykierski, Dorit. ha-Ṿaʻadah ha-sodit shel Froid: Ḥaḳirah be-ʻiḳvot teʼoryat ha-ḳevutsot shel Biyon. Tel Aviv: Resling, 2009.

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ha-Ṿaʻadah ha-sodit shel Froid: Ḥaḳirah be-ʻiḳvot teʼoryat ha-ḳevutsot shel Biyon. Tel Aviv: Resling, 2009.

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Aderinwale, Ayodele. Women and peace in Nigeria: Strategy for sustainable development : a summary report of a congress and training report organised jointly by the Africa Leadership Forum and Shell Petroleum Development Company of Nigeria Limited (SPDC) in Abuja, Nigeria, April 1-7, 2002. Benja-Ota, Ogun State, Nigeria: ALF Publications, 2002.

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Yishai, Yael. Ḳevutsot inṭeres be-Yiśraʾel: Mivḥanah shel demoḳraṭyah. Tel Aviv: ʻAm ʻoved, 1987.

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MacDonald, Kevin B. A people that shall dwell alone: Judaism as a group evolutionary strategy. Westport, Conn: Praeger, 1994.

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Śarit, Baits-Moraʼi, and Mosad le-viṭuaḥ leʼumi. Minhal ha-meḥḳar ṿeha-tikhnun., eds. Sherut psikhologi be-vate avot shel Mishʻan. Yerushalayim: ha-Mosad le-viṭuaḥ leʼumi, Minhal ha-meḥḳar ṿeha-tikhnun, 1990.

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Book chapters on the topic "Shell Group"

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Bell, Charles. "Using the Shell with Group Replication." In Introducing MySQL Shell, 337–66. Berkeley, CA: Apress, 2019. http://dx.doi.org/10.1007/978-1-4842-5083-9_8.

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Bell, Charles. "Example: Group Replication Setup and Administration." In Introducing MySQL Shell, 367–91. Berkeley, CA: Apress, 2019. http://dx.doi.org/10.1007/978-1-4842-5083-9_9.

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Jordan, Grant. "Three Styles of Decision-making: Electoral Resolution, Group Conflict, Group/Governmental Consultation." In Shell, Greenpeace and the Brent Spar, 26–74. London: Palgrave Macmillan UK, 2001. http://dx.doi.org/10.1057/9781403905291_2.

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Grayson, Leslie E. "Planning in the Royal Dutch/Shell Group." In Who and How in Planning for Large Companies, 82–110. London: Palgrave Macmillan UK, 1987. http://dx.doi.org/10.1007/978-1-349-08412-8_5.

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Rumpf, Maria. "Stakeholder Ansatz im Fall Royal Dutch/ Shell Group." In Fallstudien zum Internationalen Management, 655–73. Wiesbaden: Gabler Verlag, 2000. http://dx.doi.org/10.1007/978-3-663-10032-4_46.

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Ghana, Priyabrata. "Closed Shell Heavier Tetrylidyne Complexes of Group 6 Metals." In Synthesis, Characterization and Reactivity of Ylidyne and μ-Ylido Complexes Supported by Scorpionato Ligands, 19–75. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-02625-7_2.

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Ghana, Priyabrata. "Open-Shell Heavier Tetrylidyne Complexes of Group 6 Transition Metals." In Synthesis, Characterization and Reactivity of Ylidyne and μ-Ylido Complexes Supported by Scorpionato Ligands, 77–81. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-02625-7_3.

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Filippenko, George V. "Waves with the Negative Group Velocity in the Cylindrical Shell, Filled with Compressible Liquid." In Advances in Mechanical Engineering, 93–104. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72929-9_11.

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Eremeyev, Victor A., and Wojciech Pietraszkiewicz. "Elastic Shells, Material Symmetry Group." In Encyclopedia of Continuum Mechanics, 816–22. Berlin, Heidelberg: Springer Berlin Heidelberg, 2020. http://dx.doi.org/10.1007/978-3-662-55771-6_192.

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Judd, Brian. "Group Theory for Atomic Shells." In Springer Handbook of Atomic, Molecular, and Optical Physics, 75–85. New York, NY: Springer New York, 2006. http://dx.doi.org/10.1007/978-0-387-26308-3_3.

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Conference papers on the topic "Shell Group"

1

Samuell, Gemma. "Shell v-power 'shapeshifter'." In SIGGRAPH '16: Special Interest Group on Computer Graphics and Interactive Techniques Conference. New York, NY, USA: ACM, 2016. http://dx.doi.org/10.1145/2897841.2936767.

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Suk-Ho Choi, Sung Kim, Sung Won Hwang, Chang Oh Kim, Taehyun Kim, and R. G. Elliman. "Blue-light emission from crystalline Si/silica core/shell nanowires." In 2008 5th IEEE International Conference on Group IV Photonics. IEEE, 2008. http://dx.doi.org/10.1109/group4.2008.4638107.

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VanEngen Spivey, Amelia G. "Group velocity dispersion of CdSSe/ZnS core/shell colloidal quantum dots." In Frontiers in Optics. Washington, D.C.: OSA, 2014. http://dx.doi.org/10.1364/fio.2014.fth4d.4.

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Norman, Richard E., Ian A. Sigal, Sophie M. K. Rausch, Inka Tertinegg, Armin Eilaghi, Sharon Portnoy, John G. Sled, John G. Flanagan, and C. Ross Ethier. "Mechanics of Individual-Specific Corneoscleral Shell Models." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192576.

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Glaucoma is a group of diseases involving a progressive optic neuropathy of unknown etiology. It is one of the leading causes of blindness worldwide. It has been postulated that glaucomatous optic neuropathy may result from mechanical stresses on the optic nerve fibers passing through the lamina cribrosa (LC), from ischemia in the LC region, or from a combination of these two.
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Slate, Sean, Mathew Fuini, Damion Rose, Alexander Kutterer, Brandon Patton, Windell Cox, and Messiha Saad. "Design of a Hydrogen Fuel Cell Vehicle in the Capstone Design Course." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11466.

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The capstone course in Mechanical engineering at North Carolina A&T State University (NCA&TSU) is divided into two semesters. Team design projects begin in the fall semester and continued during the following spring semester. North Carolina State University, we, like virtually all other engineering programs, require a capstone course involving a major design project. This year a team of four mechanical engineering students and two electrical engineering students has decided to design and build a fuel efficient hydrogen fuel cell vehicle to compete in the 2009 Shell Eco-Marathon. The competition is designed to provide engineering students with a real life design experience. The objective of the competition is to encourage innovation and foster the development of sustainable mobility. Participants can design a vehicle for the Prototype Group or the Urban Concept Group. The Prototype Group allows maximum technical creativity, while imposing minimum design restrictions. The Urban Concept Group is closer to actual road going vehicles and addresses current transportation requirements. Both groups must meet the design criteria and meet safety standards provided by the 2009 Shell Eco-Marathon Official Rules. Participants must also select from a list of Shell approved energy sources to power their vehicles. The list includes both traditional fuels and alternative fuels. The main objective of the competition is maximum fuel efficiency. This year NCA&T Shell Eco-Marathon team has decided to enter the Prototype Group and has selected Hydrogen as the energy source. Our team placed in the third place in the hydrogen fuel cell prototype group. The completion of the Shell Eco-Marathon design project will serves as a valuable learning experience, while demonstrating the technical abilities of the students.
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Prakash, A. "Thermo-Kinetic Study of Core-Shell Nanothermites." In SHOCK COMPRESSION OF CONDENSED MATTER - 2005: Proceedings of the Conference of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP, 2006. http://dx.doi.org/10.1063/1.2263492.

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Fakheri, Ahmad. "The Shell and Tube Heat Exchanger Efficiency and Its Relation to Effectiveness." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41633.

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The heat exchanger efficiency is defined as the ratio of the actual heat transfer in a heat exchanger to the optimum heat transfer rate. The optimum heat transfer rate, qopt, is given by the product of UA and the Arithmetic Mean Temperature Difference, which is the difference between the average temperatures of hot and cold fluids. The actual rate of heat transfer in a heat exchanger is always less than this optimum value, which takes place in a balanced counter flow heat exchanger. It is shown that for parallel flow, counter flow, and shell and tube heat exchanger the efficiency is only a function of a single nondimensional parameter called Fin Analogy Number. Remarkably, the functional dependence of the efficiency of these heat exchangers on this parameter is identical to that of a constant area fin with an insulated tip. Also a general algebraic expression as well as a generalized chart is presented for the determination of the efficiency of shell and tube heat exchangers with any number of shells and even number of tube passes per shell, when the Number of Transfer Units (NTU) and the capacity ratio are known. Although this general expression is a function of the number of shells and another nondimensional group, it turns out to be almost independent of the number of shells over a wide range of practical interest. The same general expression is also applicable to parallel and counter flow heat exchangers.
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Bjorkman, Gordon S., and David P. Molitoris. "Mesh Convergence Studies for Thin Shell Elements Developed by the ASME Task Group on Computational Modeling." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57705.

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The ASME Task Group on Computational Modeling for Explicit Dynamics was founded in August 2008 for the purpose of creating a quantitative guidance document for the development of finite element models used to analyze energy-limited events using explicit dynamics software. This document will be referenced in the ASME Code Section III, Division 3 and the next revision of NRC Regulatory Guide 7.6 as a means by which the quality of a finite element model may be judged. One portion of the document will be devoted to a series of element convergence studies that can aid designers in establishing the mesh refinement requirements necessary to achieve accurate results for a variety of different elements types in regions of high plastic strain. These convergence studies will also aid reviewers in evaluating the quality of a finite element model and the apparent accuracy of its results. In this paper the authors present the results of a convergence study for an impulsively loaded propped cantilever beam constructed of LS-DYNA thin shell elements using both reduced and full integration. Three loading levels are considered; the first maintains strains within the elastic range, the second induces moderate plastic strains, and the third produces large deformations and large plastic strains.
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Molitoris, David P., Gordon S. Bjorkman, Chi-Fung Tso, and Michael Yaksh. "Mesh Convergence Studies for Thick Shell Elements Developed by the ASME Special Working Group on Computational Modeling." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-97992.

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The ASME Special Working Group on Computational Modeling for Explicit Dynamics was founded in August 2008 for the purpose of creating a quantitative guidance document for the development of finite element models used to analyze energy-limited events using explicit dynamics software. This document will be referenced in the ASME Code Section III, Division 3 and the next revision of NRC Regulatory Guide 7.6 as a means by which the quality of a finite element model may be judged. One portion of the document will be devoted to a series of element convergence studies that can aid designers in establishing the mesh refinement requirements necessary to achieve accurate results for a variety of different element types in regions of high plastic strain. These convergence studies will also aid reviewers in evaluating the quality of a finite element model and the apparent accuracy of its results. In this paper, the authors present the results of a convergence study for an impulsively loaded propped cantilever beam constructed of LS-DYNA thick shell elements using both reduced and selectively reduced integration. A large load is applied to produce large deformations and large plastic strains in the beam. The deformation and plastic strain results are then compared to similar results obtained using thin shell elements and hexahedral elements for the beam mesh.
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Yang, Feng-Chao, and Yu-Kuen Ho. "Design and Implementation of an Object-Oriented Cooperative Distributed Problem Solving Shell." In ASME 1996 Design Engineering Technical Conferences and Computers in Engineering Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-detc/eim-1133.

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Abstract In this paper an Object-Oriented Cooperative Distributed Problem Solving Shell (OOCDPSS) is presented. It is a convenient and effective building tool for the cooperative multi-agent application systems under distributed computer environment. By the Distributed Artificial Intelligence technique and the Object-Oriented concept, each agent is constructed by multi-layer structure to reduce the design complexity and give more flexibility, and they are arranged as a recurrent group structure for run-time effective management. Additionally, the idea of mediator is adopted to integrate new information systems with the existing inflexible legacy system, and the distributed whiteboard agent is used for the information interchange among the agents. This prototype system has been completed and used as the test bed of our other laboratory projects.
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Reports on the topic "Shell Group"

1

Friedl, M., N. Provos, and W. Simpson. Diffie-Hellman Group Exchange for the Secure Shell (SSH) Transport Layer Protocol. RFC Editor, March 2006. http://dx.doi.org/10.17487/rfc4419.

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Harbour, John, R. Summary of Group Development and Testing for Single Shell Tank Closure at Hanford. Office of Scientific and Technical Information (OSTI), April 2005. http://dx.doi.org/10.2172/881527.

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Unal, C., P. Sadasivan, W. L. Kubic, and J. R. White. Evaluation of mitigation strategies in Facility Group 1 double-shell flammable-gas tanks at the Hanford Site. Office of Scientific and Technical Information (OSTI), November 1997. http://dx.doi.org/10.2172/658141.

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Lokken, R. O., P. F. C. Martin, and J. W. Shade. Characterization of double-shell slurry feed grout produced in a pilot-scale test. Hanford Grout Technology Program. Office of Scientific and Technical Information (OSTI), December 1992. http://dx.doi.org/10.2172/10123556.

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Lokken, R. O., P. F. C. Martin, and J. W. Shade. Characterization of double-shell slurry feed grout produced in a pilot-scale test. Office of Scientific and Technical Information (OSTI), December 1992. http://dx.doi.org/10.2172/6601976.

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Whyatt, G. A. Pilot-scale production of grout with simulated double-shell slurry feed. Final report. Office of Scientific and Technical Information (OSTI), August 1994. http://dx.doi.org/10.2172/10183132.

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Robinson, S. M., T. M. Gilliam, and E. W. McDaniel. Heat transfer analyses for grout disposal of radioactive double-shell slurry and customer wastes. Office of Scientific and Technical Information (OSTI), April 1987. http://dx.doi.org/10.2172/6529654.

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Baushke, M. More Modular Exponentiation (MODP) Diffie-Hellman (DH) Key Exchange (KEX) Groups for Secure Shell (SSH). RFC Editor, December 2017. http://dx.doi.org/10.17487/rfc8268.

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Friedman, H. A., L. R. Dole, T. M. Gilliam, and G. C. Rogers. Radiolytic gas generation rates from Hanford RHO-CAW sludge and double-shell slurry immobilized in grout. Office of Scientific and Technical Information (OSTI), June 1985. http://dx.doi.org/10.2172/5618316.

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Hill, J. G., and B. C. Simpson. The Sort on Radioactive Waste Type model: A method to sort single-shell tanks into characteristic groups. Office of Scientific and Technical Information (OSTI), April 1994. http://dx.doi.org/10.2172/10160816.

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