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Learner Articulation As Interactional Achievement: Studying The Conversation Of Gesture, Timothy Koschmann, Curtis Lebaron Jun 2002

Learner Articulation As Interactional Achievement: Studying The Conversation Of Gesture, Timothy Koschmann, Curtis Lebaron

Publications

Studied under a variety of names (e.g., self-explanation, self-directed and generative summarization), it is now a well-accepted finding that the process of learner articulation contributes to new learning. While prior research has focused on measuring the effects of various forms of articulation on learning outcomes, this report focuses on how such articulation maybe accomplished, moment to moment and turn by turn. Specifically, it documents some of the ways in which participants use their bodies and, in particular, their hands while displaying what they know. It presents fine-grained analyses of three videotaped fragments of naturally occurring interaction among medical teachers and …

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Order Submission Strategy And The Curious Case Of Marketable Limit Orders, Mark Peterson, Erik Sirri Jun 2002

Order Submission Strategy And The Curious Case Of Marketable Limit Orders, Mark Peterson, Erik Sirri

Publications

No abstract provided.

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Structure And Magnetic Properties Of The Mnbi Low Temperature Phase, J. B. Yang, W. B. Yelon, W. J. James, Q. Cai, S. Roy, N. Ali May 2002

Structure And Magnetic Properties Of The Mnbi Low Temperature Phase, J. B. Yang, W. B. Yelon, W. J. James, Q. Cai, S. Roy, N. Ali

Publications

High purity MnBi low temperature phase has been prepared and analyzed using magnetic measurements and neutron diffraction. The low-temperature phase of the MnBi alloy has a coercivity μ0iHc of 2.0 T at 400 K, and exhibits a positive temperature coefficient from 0 to at least 400 K. The neutron data refinement indicated that the Mn atom changes its spin direction from c axis above room temperature to nearly perpendicular to the c axis at 50 K. A canted magnetic structure has been observed below 200 K. The anisotropy field increases with increasing temperature which gives rise …

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The Relationship Between Magnetic Interactions And Near Neighbor Interatomic Distances In The Transition Metal Sublattice Of R(Mn/Fe)6a6 (R=Nd Or Sm, A=Ge Or Sn), G. K. Marasinghe, J. Han, W. J. James, W. B. Yelon, N. Ali May 2002

The Relationship Between Magnetic Interactions And Near Neighbor Interatomic Distances In The Transition Metal Sublattice Of R(Mn/Fe)6a6 (R=Nd Or Sm, A=Ge Or Sn), G. K. Marasinghe, J. Han, W. J. James, W. B. Yelon, N. Ali

Publications

The magnetic and crystallographic structures of R(Fe/Mn)6A6 (R=Nd or Sm and A=Ge or Sn) intermetallics have been investigated using x-ray and neutron diffraction techniques and superconducting quantum interference device magnetic measurements. For both stannides (A=Sn) and germanides (A=Ge), the lattice contracts with increasing iron content. In the case of the stannides, substitution of manganese by iron enhances the saturation magnetization and Curie temperature at low iron concentrations (x≤2) suggesting the presence of an extremely rare occurrence, positive coupling between iron and manganese magnetic moments. In contrast, the magnetic properties of the germanides deteriorate rapidly as …

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Masting By Eighteen New Zealand Plant Species: The Role Of Temperature As A Synchronizing Cue, Eric M. Schauber, Dave Kelly, Peter Turchin, Chris Simon, William G. Lee, Robert B. Allen, Ian J. Payton, Peter R. Wilson, Phil E. Cowan, R E. Brockie May 2002

Masting By Eighteen New Zealand Plant Species: The Role Of Temperature As A Synchronizing Cue, Eric M. Schauber, Dave Kelly, Peter Turchin, Chris Simon, William G. Lee, Robert B. Allen, Ian J. Payton, Peter R. Wilson, Phil E. Cowan, R E. Brockie

Publications

Masting, the intermittent production of large flower or seed crops by a population of perennial plants, can enhance the reproductive success of participating plants and drive fluctuations in seed-consumer populations and other ecosystem components over large geographic areas. The spatial and taxonomic extent over which masting is synchronized can determine its success in enhancing individual plant fitness as well as its ecosystem-level effects, and it can indicate the types of proximal cues that enable reproductive synchrony. Here, we demonstrate high intra- and intergeneric synchrony in mast seeding by 17 species of New Zealand plants from four families across >150000 km …

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Magnetic And Electronic Transport Properties Of Ybxca1−Xmno3 Compounds, Yongquan Guo, Sujoy Roy, Naushad Ali, Mauro R. Sardela May 2002

Magnetic And Electronic Transport Properties Of Ybxca1−Xmno3 Compounds, Yongquan Guo, Sujoy Roy, Naushad Ali, Mauro R. Sardela

Publications

The polycrystalline YbxCa1−xMnO3 (x=0.1,0.2) were studied by x-ray powder diffraction, magnetic, and electrical resistivity measurements. The YbxCa1−xMnO3 crystallizes in an orthogonally distorted perovskite structure, and shows the ferromagnetic ordering with TC more than 110 K. However, the field dependence of magnetization and electrical resistivity exhibits very complicated behavior. A magnetic field induced insulator–metal transition has been found in the Yb0.2Ca0.8MnO3 compound. In addition, the large asymmetry in magnetization and resistivity hysteresis loops has been observed in this compound at 10 …

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Structure And Magnetic Properties Of Rfe6−Xga6+X (R=Rare Earth), Yongquan Guo, Naushad Ali, Mauro R. Sardela May 2002

Structure And Magnetic Properties Of Rfe6−Xga6+X (R=Rare Earth), Yongquan Guo, Naushad Ali, Mauro R. Sardela

Publications

The crystal structures and magnetic properties of RFe6−xGa6+x (R=Ce, Pr, Nd, Sm, and Gd) alloys have been investigated by x-ray powder diffraction and magnetic measurement. A ternary intermetallic compound with an orthorhombic ScFe6Ga6 type structure is found in these alloys. The lattice parameter contraction is observed when the higher atomic number lanthanides are substituted into the intermetallic. In each unit cell, there are six nonequivalent crystal positions, i.e., 2a, 4e, 4f, 4g, 4h, and 8k, which are occupied by 2R, 4GaI, 4(FeI,Ga), 4GaII, 4GaIII, …

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Uaa Student Showcase Journal: Recognizing Excellence (2002), N/A N/A Apr 2002

Uaa Student Showcase Journal: Recognizing Excellence (2002), N/A N/A

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No abstract provided.

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John Boyle O'Reilly & Moondyne (1878), Susanna Ashton Apr 2002

John Boyle O'Reilly & Moondyne (1878), Susanna Ashton

Publications

Arrested for treason against the British Crown and deported to the penal colonies of Australia, the Irish revolutionary John Boyle O'Reilly managed to escape to the United States and within a few years became one of Boston's most prominent political and literary figures, one of the best known Irish immigrants in the United States, and one of the most charismatic individuals of the late nineteenth century. He wrote some of the most popular poetry of the period as well as one obscure but swashbuckling novel, Moondyne (1878), based in part upon the spectacular

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Process-Product Ambiguity: Theorizing A Perspective On World Wide Web Argumentation, Sean Williams Apr 2002

Process-Product Ambiguity: Theorizing A Perspective On World Wide Web Argumentation, Sean Williams

Publications

No abstract provided.

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Human Factors Survey Of Aviation Maintenance Technical Manuals, Alex Chaparro, Loren S. Groff Apr 2002

Human Factors Survey Of Aviation Maintenance Technical Manuals, Alex Chaparro, Loren S. Groff

Publications

The reported work is part of a 3 phased effort to identify human factors issues in the development of aviation technical manuals, and make recommendations for the improvement of those documents. Phase 1 of this research effort surveyed the procedures used by five manufacturers to develop maintenance documentation. Several human factors issues were identified in the development process employed by these manufacturers. They included the reactive rather than proactive use of user evaluations, the limited use of user input and procedure validation, no systematic attempts to track error, and the lack of standards for measuring document quality. Given the issues …

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Racial Integration As An Innovation: Empirical Evidence From Sports Leagues, Robert E. Mccormick, Brian L. Goff, Robert D. Tollison Mar 2002

Racial Integration As An Innovation: Empirical Evidence From Sports Leagues, Robert E. Mccormick, Brian L. Goff, Robert D. Tollison

Publications

This paper treats racial integration as an innovation in economic process in which economic entities find it advantageous to utilize potentially more productive inputs previously unavailable due to law, custom, or managerial discretion. Data on the racial integration of Major League Baseball and Atlantic Coast Conference basketball are employed to address this issue. The central question examined is which type of team integrated first—losers or winners? The results strongly support the idea that entrepreneurship trumps competitive rivalry; that is, winning teams led the process of racial integration.

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Protracted Reproduction In Sunfish: The Temporal Dimension In Fish Recruitment Revisited, James E. Garvey, Tomasz P. Herra, William C. Leggett Feb 2002

Protracted Reproduction In Sunfish: The Temporal Dimension In Fish Recruitment Revisited, James E. Garvey, Tomasz P. Herra, William C. Leggett

Publications

Understanding how life histories influence reproductive success under uncertain conditions is necessary to predict population dynamics. For many organisms, protracted reproduction may increase expected offspring recruitment in variable environments, requiring that temporal patterns of reproduction be considered when developing management or conservation strategies. We explored the interrelationships among birth date, production of embryos on nests, survival of larvae to the open-water stage, and survival of juveniles through the first fall and winter of life for bluegill and pumpkinseed sunfish (Lepomis macrochirus and L. gibbosus) in Lake Opinicon, Ontario, during May 1998 through May 1999. Age-0 sunfish were sampled …

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A Plan For The Future Of The Presumpscot River: Fisheries Conditions, Issues And Opportunities, Presumpscot River Management Plan Steering Committee, Coastal Conservation Association, Greater Portland Council Of Governments, Hannaford Brothers, Maine Atlantic Salmon Commission, Maine Dept. Of Environmental Protection, Maine Dept. Of Inland Fisheries & Wildlife, Maine Dept. Of Marine Resources, Usda Natural Resources Conservation Service, Portland Trails, Portland Water District, Presumpscot River Watch, U.S. Environmental Protection Agency, U.S. Fish & Wildlife Service Jan 2002

A Plan For The Future Of The Presumpscot River: Fisheries Conditions, Issues And Opportunities, Presumpscot River Management Plan Steering Committee, Coastal Conservation Association, Greater Portland Council Of Governments, Hannaford Brothers, Maine Atlantic Salmon Commission, Maine Dept. Of Environmental Protection, Maine Dept. Of Inland Fisheries & Wildlife, Maine Dept. Of Marine Resources, Usda Natural Resources Conservation Service, Portland Trails, Portland Water District, Presumpscot River Watch, U.S. Environmental Protection Agency, U.S. Fish & Wildlife Service

Publications

No abstract provided.

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Exploiting Dendritic Cells To Improve Vaccine Efficacy, Ralph M. Steinman, Melissa Pope Jan 2002

Exploiting Dendritic Cells To Improve Vaccine Efficacy, Ralph M. Steinman, Melissa Pope

Publications

[No abstract available]

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The Simian Immunodeficiency Virus Δnef Vaccine, After Application To The Tonsils Of Rhesus Macaques, Replicates Primarily Within Cd4+ T Cells And Elicits A Local Perforin-Positive Cd8+ T-Cell Response, Christiane P. Stahl-Hennig, Ralph M. Steinman, Peter Ten Haaft Jan 2002

The Simian Immunodeficiency Virus Δnef Vaccine, After Application To The Tonsils Of Rhesus Macaques, Replicates Primarily Within Cd4+ T Cells And Elicits A Local Perforin-Positive Cd8+ T-Cell Response, Christiane P. Stahl-Hennig, Ralph M. Steinman, Peter Ten Haaft

Publications

Deletion of the nef gene from simian immunodeficiency virus (SIV) strain SIVmac239 yields a virus that undergoes attenuated growth in rhesus macaques and offers substantial protection against a subsequent challenge with some SIV wild-type viruses. We used a recently described model to identify sites in which the SIVΔnef vaccine strain replicates and elicits immunity in vivo. A high dose of SIVΔnef was applied to the palatine and lingual tonsils, where it replicated vigorously in this portal of entry at 7 days. Within 2 weeks, the virus had spread and was replicating actively in axillary lymph nodes, primarily in extrafollicular T-cell-rich …

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Immune Tolerance After Delivery Of Dying Cells To Dendritic Cells In Situ, Kang Z. Liu, Tomonori Iyoda, Marzena Saternus Jan 2002

Immune Tolerance After Delivery Of Dying Cells To Dendritic Cells In Situ, Kang Z. Liu, Tomonori Iyoda, Marzena Saternus

Publications

Peripheral immune tolerance is believed to be induced by the processing and presentation of self-tissues that die during physiologic tissue turnover. To examine the mechanism that mediates tolerance, we injected mice with dying syngeneic TAP-/- splenocytes loaded with small amounts of the protein antigen, ovalbumin (OVA). After ingestion and presentation of cell-associated OVA by the CD8+ subset of dendritic cells in situ, large numbers of antigen-reactive, CD8+ T cell receptor (TCR) transgenic T lymphocytes were driven into cell cycle, but then the T cells were deleted. The animals were also tolerant to challenge with OVA in complete …

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Expression Of A Functional Eotaxin (Cc Chemokine Ligand 11) Receptor Ccr3 By Human Dendritic Cells, Sylvia Beaulieu, Davide E. Robbiani, Xixuan Du Jan 2002

Expression Of A Functional Eotaxin (Cc Chemokine Ligand 11) Receptor Ccr3 By Human Dendritic Cells, Sylvia Beaulieu, Davide E. Robbiani, Xixuan Du

Publications

Critical to the function of Ag-presenting dendritic cells (DCs) is their capacity to migrate to lymphoid organs and to sites of inflammation. A final stage of development, termed maturation, yields DCs that are strong stimulators of T cell-mediated immunity and is associated with a remodeling of the cell surface that includes a change in the levels of expression of many molecules, including chemokine receptors. We show in this study that CCR3, a chemokine receptor initially discovered on eosinophils, is also expressed by human DCs that differentiate from blood monocytes, DCs that emigrate from skin (epidermal and dermal DCs), and DCs …

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The Cd8+ Dendritic Cell Subset Selectively Endocytoses Dying Cells In Culture And In Vivo, Tomonori Iyoda, Susumu Shimoyama, Kang Z. Liu Jan 2002

The Cd8+ Dendritic Cell Subset Selectively Endocytoses Dying Cells In Culture And In Vivo, Tomonori Iyoda, Susumu Shimoyama, Kang Z. Liu

Publications

Dendritic cells (DCs) are able in tissue culture to phagocytose and present antigens derived from infected, malignant, and allogeneic cells. Here we show directly that DCs in situ take up these types of cells after fluorescent labeling with carboxyfluorescein succinimidyl ester (CFSE) and injection into mice. The injected cells include syngeneic splenocytes and tumor cell lines, induced to undergo apoptosis ex vivo by exposure to osmotic shock, and allogeneic B cells killed by NK cells in situ. The CFSE-labeled cells in each case are actively endocytosed by DCs in vivo, but only the CD8+ subset. After uptake, all of …

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Preparation Of Clinical-Grade Recombinant Canarypox-Human Immunodeficiency Virus Vaccine-Loaded Human Dendritic Cells, Mary A. Marovich, John R. Mascola, Michael A. Eller Jan 2002

Preparation Of Clinical-Grade Recombinant Canarypox-Human Immunodeficiency Virus Vaccine-Loaded Human Dendritic Cells, Mary A. Marovich, John R. Mascola, Michael A. Eller

Publications

Preclinical data are reported that support a human immunodeficiency virus (HIV) vaccine strategy using recombinant canarypox-HIV vectors (ALVAC-HIV) to load human dendritic cells (DCs) with HIV antigens. Clinical-grade DCs were infected with good manufacturing practice-grade ALVAC-HIV vaccine constructs. ALVAC infection, HIV gene expression, and DC viability and function were monitored by use of immunohistochemistry, flow cytometry, blastogenesis assays, antigen-specific interferon (IFN)-γ enzyme-linked immunospot assay, and enzyme-linked immunosorbent assay protein detection. The vaccines infected both immature and mature DCs, and intracellular HIV-1 Gag protein was detected within hours. ALVAC-HIV induced DC maturation that was mediated by tumor necrosis factor-α and induced …

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Endogenously Expressed Nef Uncouples Cytokine And Chemokine Production From Membrane Phenotypic Maturation In Dendritic Cells, Davorka Messmer, Jean M. Jacqué Jan 2002

Endogenously Expressed Nef Uncouples Cytokine And Chemokine Production From Membrane Phenotypic Maturation In Dendritic Cells, Davorka Messmer, Jean M. Jacqué

Publications

Immature dendritic cells (DCs), unlike mature DCs, require the viral determinant nef to drive immunodeficiency virus (SIV and HIV) replication in coculture with CD4+ T cells. Since immature DCs may capture and get infected by virus during mucosal transmission, we hypothesized that Nef associated with the virus or produced during early replication might modulate DCs to augment virus dissemination. Adenovirus vectors expressing nef were used to introduce nef into DCs in the absence of other immunodeficiency virus determinants to examine Nef-induced changes that might activate immature DCs to acquire properties of mature DCs and drive virus replication. Nef expression …

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Increased Macrophage Infection Upon Subcutaneous Inoculation Of Rhesus Macaques With Simian Immunodeficiency Virus-Loaded Dendritic Cells Or T Cells But Not With Cell-Free Virus, Ralf Ignatius, Klara Tenner-Ràcz, Davorka Messmer Jan 2002

Increased Macrophage Infection Upon Subcutaneous Inoculation Of Rhesus Macaques With Simian Immunodeficiency Virus-Loaded Dendritic Cells Or T Cells But Not With Cell-Free Virus, Ralf Ignatius, Klara Tenner-Ràcz, Davorka Messmer

Publications

Information on the establishment of immunodeficiency virus infection through transmission of infected cells is sparse. Dendritic cells (DCs) and T cells may be central to the onset and subsequent spread of infection following mucosal exposure. To directly investigate the consequences of virus being introduced by DCs or T cells, we reinjected ex vivo simian immunodeficiency virus (SIV)-loaded autologous immature DCs and T cells subcutaneously (s.c.) into healthy macaques, s.c. injection of cell-bound virus was used to mirror what may happen if virus-loaded cells pass through an epithelium or perhaps DCs and T cells that immediately entrap cell-free virus, having just …

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The Bodger Dialogues, Richard P. Richter Jan 2002

The Bodger Dialogues, Richard P. Richter

Publications

This is an account of Ursinus College during the period 1965-1994, told in a literary format by former President Richard P. Richter in 2002.

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Fisheries Conditions, Issues And Options For The Presumpscot River, A Background Paper For The Development Of A Plan For The Future Of The Presumpscot River, As Distributed At The June 2002 Public Meetings, Casco Bay Estuary Project, Presumpscot River Plan Steering Committee, Land & Water Associates Jan 2002

Fisheries Conditions, Issues And Options For The Presumpscot River, A Background Paper For The Development Of A Plan For The Future Of The Presumpscot River, As Distributed At The June 2002 Public Meetings, Casco Bay Estuary Project, Presumpscot River Plan Steering Committee, Land & Water Associates

Publications

No abstract provided.

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Undergraduate Student Internships In Natural Resources At Virginia 4-H Educational Centers, Jeff Kirwan, Barry Fox, Barry A. Garst Jan 2002

Undergraduate Student Internships In Natural Resources At Virginia 4-H Educational Centers, Jeff Kirwan, Barry Fox, Barry A. Garst

Publications

Virginia has six 4-H educational centers that provide residential camping experiences for over 22,000 youth per year, the second largest 4-H camping program in the United States. These children may have many learning opportunities in the areas of natural resources and outdoor living skills. Beginning in 1995, the Chesapeake Bay Program in cooperation with the Virginia Division of Soil and Water Conservation provided funds for water quality instructors at each of the 4-H Centers. In 1998, the Virginia Forestry Educational Foundation began supporting a similar internship program for undergraduate students to serve as forestry instructors. Nearly 50 undergraduate students have …

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Book Review - The Caddisfly Family Phryganeidae (Trichoptera), John C. Morse Jan 2002

Book Review - The Caddisfly Family Phryganeidae (Trichoptera), John C. Morse

Publications

No abstract provided.

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Human Dendritic Cells Activate Resting Natural Killer (Nk) Cells And Are Recognized Via The Nkp30 Receptor By Activated Nk Cells, Guido Ferlazzo, Mingli Tsang, Lorenzo Moretta Jan 2002

Human Dendritic Cells Activate Resting Natural Killer (Nk) Cells And Are Recognized Via The Nkp30 Receptor By Activated Nk Cells, Guido Ferlazzo, Mingli Tsang, Lorenzo Moretta

Publications

During the innate response to many inflammatory and infectious stimuli, dendritic cells (DCs) undergo a differentiation process termed maturation. Mature DCs activate antigen-specific naive T cells. Here we show that both immature and mature DCs activate resting human natural killer (NK) cells. Within 1 wk the NK cells increase two- to fourfold in numbers, start secreting interferon (IFN)-γ, and acquire cytolytic activity against the classical NK target LCL721.221. The DC-activated NK cells then kill immature DCs efficiently, even though the latter express substantial levels of major histocompatibility complex (MHC) class I. Similar results are seen with interleukin (IL)-2-activated NK cell …

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Cumulative Impacts To Environmental Conditions On The Presumpscot River And Its Shorelands, As Distributed At The June 2002 Public Meetings, Casco Bay Estuary Project, Presumpscot River Plan Steering Committee, Land & Water Associates Jan 2002

Cumulative Impacts To Environmental Conditions On The Presumpscot River And Its Shorelands, As Distributed At The June 2002 Public Meetings, Casco Bay Estuary Project, Presumpscot River Plan Steering Committee, Land & Water Associates

Publications

No abstract provided.

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A Method For Simulating Systems Of Correlated Binary Data, Todd C. Headrick Jan 2002

A Method For Simulating Systems Of Correlated Binary Data, Todd C. Headrick

Publications

An efficient algorithm is derived for generating systems of correlated binary data. The procedure allows for the specification of all pairwise correlations within each system. Intercorrelations between systems can be specified qualitatively.The procedure requires the simultaneous solution of a system of equations for obtaining the threshold probabilities to generate each system of binary data. A numerical example is provided to demonstrate that the procedure generates correlated binary variables that yield correlations in close agreement with the specified population correlations.

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Fuel Consumption Modeling Of A Transport Category Aircraft Using Flight Operations Quality Assurance Data: A Literature Review, Alan J. Stolzer Jan 2002

Fuel Consumption Modeling Of A Transport Category Aircraft Using Flight Operations Quality Assurance Data: A Literature Review, Alan J. Stolzer

Publications

"Fuel is a major cost expense for air carriers. A typical airline spends 10% of its operating budget on the purchase of jet fuel, which even exceeds its expenditures on aircraft acquisitions. Thus, it is imperative that fuel consumption be managed as wisely as possible. The implementation of Flight Operations Quality Assurance (FOQA) programs at airlines may be able to assist in this management effort. The purpose of the study is to examine the literature regarding fuel consumption by air carriers, the literature related to air carrier fuel conservation efforts, and the literature related to the appropriate statistical methodologies to …

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