1,511 research outputs found

    An assessment of the industrial cogeneration market for parabolic dish systems

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    The value analysis technique used is straightforward. Maximum allowable life-cycle system cost for the cogeneration system is determined as the sum of the present value of fuels displaced plus the present value of revenues from exported power. Each conventional fuel displaced is described by a unit cost in the first year, a uniform annual consumption rate, and a uniform annual escalation rate for unit cost. Exported energy flows are treated the same as displaced energy

    Distributed control using linear momentum exchange devices

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    MSFC has successfully employed the use of the Vibrational Control of Space Structures (VCOSS) Linear Momentum Exchange Devices (LMEDs), which was an outgrowth of the Air Force Wright Aeronautical Laboratory (AFWAL) program, in a distributed control experiment. The control experiment was conducted in MSFC's Ground Facility for Large Space Structures Control Verification (GF/LSSCV). The GF/LSSCV's test article was well suited for this experiment in that the LMED could be judiciously placed on the ASTROMAST. The LMED placements were such that vibrational mode information could be extracted from the accelerometers on the LMED. The LMED accelerometer information was processed by the control algorithms so that the LMED masses could be accelerated to produce forces which would dampen the vibrational modes of interest. Experimental results are presented showing the LMED's capabilities

    An ultrahigh-speed digitizer for the Harvard College Observatory astronomical plates

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    A machine capable of digitizing two 8 inch by 10 inch (203 mm by 254 mm) glass astrophotographic plates or a single 14 inch by 17 inch (356 mm by 432 mm) plate at a resolution of 11 microns per pixel or 2309 dots per inch (dpi) in 92 seconds is described. The purpose of the machine is to digitize the \~500,000 plate collection of the Harvard College Observatory in a five year time frame. The digitization must meet the requirements for scientific work in astrometry, photometry, and archival preservation of the plates. This paper describes the requirements for and the design of the subsystems of the machine that was developed specifically for this task.Comment: 12 pages, 9 figures, 1 table; presented at SPIE (July, 2006) and published in Proceeding

    System average rates of U.S. investor-owned electric utilities : a statistical benchmark study

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    Using multiple regression methods, we have undertaken a statistical "benchmark" study comparing system average electricity rates charged by three California utilities with 96 other US utilities over the 1984-93 time period. Although system average electricity rates are much higher in California than for the national average, we conclude that use of such unadjusted prices provides no meaningful information on how one evaluates the performance of utility management. Rather, we find that average electricity prices are affected to a large extent by a number of factors outside direct and immediate management control, such as local costs of doing business, the availability of low-cost generation sources (e.g., hydro and coal), customer and service territory characteristics such as customer density, use per customer, and a number of regulatory and environmental factors. Once one controls for these various factors, the remaining impact of utility management on system average rates is rather modest, and for the California utilities the impact of utility management (relative to the national average) is insignificantly different from zero. This finding of no difference in prices, holding constant the effects of factors outside of California utilities' control, is robust, being sustained in a large number of alternative models and estimation methods.Financial support from San Diego Gas & Electric Company

    Cambridge, Trinity College R.17.1 (987): "Eadwine Psalter" ("Canterbury Psalter") (with London, British Library, Add. 37472(1) [165a], London, Victoria and Albert Museum 661 [319a], New York, Pierpont Morgan Library, M. 521 and M. 724 [332a])

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    85. Cambridge, Trinity College R. 17. 1 (987) "Eadwine Psalter" ("Canterbury Psalter") (with London, British Library, Add. 37472(1) [165a], London, Victoria and Albert Museum 661 [319a], New York, Pierpont Morgan Library, M. 521 and M. 724 [332a]) [Ker 91, Gneuss -) HISTORY: A lavishly illustrated, large-format triple Psalter containing the Gallicanum, Romanum, and Hebraicum versions of the Psalms, with marginal and interlinear glosses to the Gallicanum from the "Glossa Ordinaria" ("parva glosatura"), a continuous interlinear OE gloss to the Romanum, and a continuous interlinear Anglo-Norman (French) gloss to the Hebraicum. Probably written at Christ Church, Canterbury; dated by the script to the 1150s (T. Webber in Gibson et al. 1992: 24). The Psalter receives its common title from the large illustration of the scribe Eadwine on f. 283v, a feature added about twenty years after the Psalter was written. A direct copy of this manuscript was made in the late 12c, now Paris Bibliotheque Nationale lat. 8846 [432]. The Psalter is listed in Henry Eastry's (Prior of Christ Church, 1284- 1331) early 14c inventory of the Christ Church library (London, BL Cotton Galba E. iv, ed. James 1903: 51, no. 323), where it appears as "Tripartitum psalterium Edwini:' As T. A. Heslop notes (in Gibson et al. 1992: 193-94), the earliest direct indication that the codex belonged to the monastic community comes in a partly erased memorandum (f. 4v): 'Istud psalteriu<m> sancte ecc<les>ie Cantuarien<sis> traditu<m> est ad | usum d<omi>ni Thome Archiep(iscop)i eiusdem ecc<les>ie p<er> Priorem | & capit<u>l<u>m eiusdem ad suu<m> beneplacitu<m>. p<er> modu<m> mutui' (facs. in Gibson et al. 1992: pl. 2d; ed. Verfaillie-Markey 1985, who suggests that the Thomas referred to is likely Archbishop Thomas Arundel, 1397, 1399-1414). The "Eadwine Psalter" may still have remained with the archbishops in the mid-16c, as indicated by another, more thoroughly erased, inscription on f. 1r: 'Liber Academie Cantabrigiensis ex dona | Richardi Arkynstall anno d[omi]ni 1584' (ed. Heslop in Gibson et al. 1992: 194; see n. 4, and pls. 2e, f ). Arkinstall, who matriculated at Queen's College, Cambridge, 1584-1585, may have appropriated the codex from Richard Cox, Bishop of Ely (1559-1581 ), when he was a student there (for a discussion of this complex matter, see Heslop in Gibson et al. 1992: 194; see also Keynes 1992: 40 ). The manuscript remained at Canterbury until it was presented to Trinity College by Thomas Nevile, Dean of Canterbury (1597-1615), and Master of Trinity (now the inside pastedown, Nevile's bookplate and label of Trinity College, was formerly on f. 2r, as in the film). Binding is from the 17c (see N. Pickwoad in Gibson et al. 1992: 9). Edited and translated in 1630 by William L'Isle (1569?-1637), one-time fellow of King's College, Cambridge; edition preserved in Oxford, Bodi. Lib. Laud Misc. 201 (see Pulsiano 2000). For a full discussion of the history of the manuscript, see T. A. Heslop and D. McKitterick, as well as M. Gibson in Gibson et al. 1992: 193-213. In all probability the "Eadwine Psalter;' like its counterpart, Paris BN lat. 8846, originally had prefatory picture pages containing Old Testament and Gospel scenes which were removed; they are thought to still exist as four dispersed leaves: New York, Pierpont Morgan Library, M. 521 and M. 724 [332a], London, BL Additional 37472(1) [165a], and London, Victoria and Albert Museum MS 661 [319a]. They were likely removed before the manuscript came to Trinity College in the early 17 c, and may have been removed when the book was bound around the same time, perhaps in London. They appeared in the private collection of William Young Ottely, who sold them in 1838 (for the histories of the individual leaves see their individual descriptions, also G. Henderson in Gibson et al. 1992: 25-42)

    Definition of ground test for verification of large space structure control

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    Control theory and design, dynamic system modelling, and simulation of test scenarios are the main ideas discussed. The overall effort is the achievement at Marshall Space Flight Center of a successful ground test experiment of a large space structure. A simplified planar model of ground test experiment of a large space structure. A simplified planar model of ground test verification was developed. The elimination from that model of the uncontrollable rigid body modes was also examined. Also studied was the hardware/software of computation speed

    Noise in Electron Devices

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    Contains reports on three research projects.Joint Services Electronics Program (Contract DA36-039-AMC-03200(E)

    Neuropsychological Outcomes of U.S. Veterans with Report of Remote Blast-Related Concussion and Current Psychopathology

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    This study explored whether remote blast-related MTBI and/or current Axis I psychopathology contribute to neuropsychological outcomes among OEF/OIF veterans with varied combat histories. OEF/OIF veterans underwent structured interviews to evaluate history of blast-related MTBI and psychopathology and were assigned to MTBI (n = 18), Axis I (n = 24), Co-morbid MTBI/Axis I (n = 34), or post-deployment control (n = 28) groups. A main effect for Axis I diagnosis on overall neuropsychological performance was identified (F(3,100) = 4.81; p = .004), with large effect sizes noted for the Axis I only (d = .98) and Co-morbid MTBI/Axis I (d = .95) groups relative to the control group. The latter groups demonstrated primary limitations on measures of learning/memory and processing speed. The MTBI only group demonstrated performances that were not significantly different from the remaining three groups. These findings suggest that a remote history of blast-related MTBI does not contribute to objective cognitive impairment in the late stage of injury. Impairments, when present, are subtle and most likely attributable to PTSD and other psychological conditions. Implications for clinical neuropsychologists and future research are discussed. (JINS, 2012, 18, 1–11
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