3,532 research outputs found

    Guidelines for Economic Evaluation of Public Sector Water Resource Projects

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    Water development plays an important role in the economy of states and regions. However, procedures for estimating the expected net worth of proposed projects have never been simple, and results have rarely been without controversy. This report presents some guidelines for the application of economic evaluation procedures in project analysis of public sector water development in North Dakota. A brief history of North Dakota water development and two case studies of North Dakota water projects are included in this report.Resource /Energy Economics and Policy,

    Missouri River Water Use in North Dakota

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    Resource /Energy Economics and Policy,

    Next generation sequencing analysis reveals a relationship between rDNA unit diversity and locus number in Nicotiana diploids

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    © 2012 Matyåƥek et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    A Study of the SP Geophysical Technique in a Campus Setting

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    The self potential (SP) method is a simple and inexpensive geophysical surveying technique, which involves measuring electrical potentials on the surface due to charge separations in the subsurface. These charge separations can arise from a number of different physical and electrochemical processes, and hence interpretations tend to be qualitative. Small anomalies are typically neglected as transient, inexplicable, or uninteresting. In contrast, large negative anomalies associated with ore bodies are noted for their constancy. In this study, an area on the campus of Memorial University was repeatedly surveyed in order to determine which natural and anthropogenic features generated SP anomalies, and whether these anomalies were constant or transient. We found anomalies associated with a building, a buried metallic pipe, trees, and subtler ground variations. The locations of anomalies, both large and small, were notably unvarying over a period of days and weeks. The building always generated a significant negative anomaly, but the sign of other anomalies (including that associated with the pipe) and the magnitude of all anomalies varied with time. In a second area dominated by a shallow sewer pipe, SP data allowed modeling of the burial depth and charge distribution of the pipe. Our results show that SP can be a useful and reliable method for shallow ground surveys, but that the time-varying nature of both sign and magnitude of small to moderate anomalies should be taken into account in data collection and interpretation. Résumé La mĂ©thode des potentiels spontanĂ©s est une technique d’exĂ©cution de levĂ©s gĂ©ophysiques simple et peu dispendieuse consistant Ă  mesurer les potentiels Ă©lectriques Ă  la surface liĂ©s aux sĂ©parations des charges dans le sous-sol. Ces sĂ©parations des charges peuvent dĂ©couler d’un certain nombre de processus physiques et Ă©lectrochimiques diffĂ©rents, de sorte que les interprĂ©tations donnĂ©es ont tendance Ă  ĂȘtre qualitatives. On nĂ©glige gĂ©nĂ©ralement les petites anomalies, les considĂ©rant comme des anomalies transitoires, inexplicables ou peu intĂ©ressantes. En revanche, on note les anomalies nĂ©gatives poussĂ©es qui sont associĂ©es aux corps minĂ©ralisĂ©s en raison de leur constance. Dans le cadre de cette Ă©tude, on a rĂ©alisĂ© des levĂ©s rĂ©pĂ©tĂ©s dans un secteur du campus de l’UniversitĂ© Memorial pour dĂ©terminer quelles particularitĂ©s naturelles et artificielles produisaient des anomalies des PS et si ces anomalies Ă©taient constantes ou transitoires. Nous avons dĂ©couvert des anomalies associĂ©es Ă  un bĂątiment, Ă  un tuyau en mĂ©tal enfoui, Ă  des arbres et Ă  des irrĂ©gularitĂ©s du terrain plus subtiles. Fait remarquable, les emplacements des anomalies, tant prononcĂ©es que minimes, n’ont pas changĂ© au cours d’une pĂ©riode de plusieurs jours et semaines. Le bĂątiment a toujours produit une anomalie nĂ©gative marquĂ©e, mais le signal d’autres anomalies (notamment celle associĂ©e au tuyau) et la magnitude de toutes les anomalies ont variĂ© au fil du temps. Dans un second secteur oĂč Ă©tait surtout prĂ©sent un tuyau d’égout peu profond, les donnĂ©es des PS ont permis la modĂ©lisation de la profondeur d’enfouissement et de la distribution des charges du tuyau. Nos rĂ©sultats rĂ©vĂšlent que la polarisation spontanĂ©e peut s’avĂ©rer une mĂ©thode utile et fiable pour les levĂ©s terrestres peu profonds, mais qu’il faudrait tenir compte de la nature variable des signaux et de la magnitude des anomalies minimes Ă  moyennes lors de la collecte et de l’interprĂ©tation des donnĂ©es. [Traduit par la redaction

    Optical Observations of the Binary Millisecond Pulsars J2145-0750 and J0034-0534

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    We report on optical observations of the low-mass binary millisecond pulsar systems J0034-0534 and J2145-0750. A faint (I=23.5) object was found to be coincident with the timing position of PSR J2145-0750. While a galaxy or distant main-sequence star cannot be ruled out, its magnitude is consistent with an ancient white dwarf, as expected from evolutionary models. For PSR J0034-0534 no objects were detected to a limiting magnitude of R=25.0, suggesting that the white dwarf in this system is cold. Using white dwarf cooling models, the limit on the magnitude of the PSR J0034-0534 companion suggests that at birth the pulsar in this system may have rotated with a period as short as 0.6 ms. These observations provide further evidence that the magnetic fields of millisecond pulsars do not decay on time scales shorter than 1 Gyr.Comment: 6 pages, uuencoded, gz -9 compressed postscript, accepted by ApJ

    Researching creatively with pupils in Assessment for Learning (AfL) classrooms on experiences of participation and consultation

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    This paper reports on an ESRC TLRP project, Consulting Pupils on the Assessment of their Learning (CPAL). The CPAL project provides an additional theoretical perspective to the ‘educational benefits’ perspective of engaging pupil voice in learning and teaching (Rudduck et al., 2003) through its exploration of pupil rights specifically in relation to assessment issues presently on the policy agenda in the Northern Ireland context – notably Assessment for Learning (AfL). An emergent framework for assessing pupil rights, based on Article 12 of the United Nations Convention on the Rights of the Child (Lundy, 2007), is being used to explore the ways in which AfL classroom practice creates the conditions for increased pupil participation and consultation. Pupil views on their AfL classroom experiences and participation are explored by means of a variety of pupil-centred, creative research methods that engage and stimulate pupils to observe, communicate and analyse their learning and assessment experiences and give meaning to them. This presentation highlights preliminary data based on a sample of 11-14 years pupils' experiences of participation and consultation in classrooms adopting AfL pedagogical principles, and identifies characteristics that support or inhibit pupil participation in their learning and the expression of their views about such matters

    Economic Simulation of Cryptocurrencies and Their Control Mechanisms

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    A cryptocurrency needs a relatively stable value if it is to fulfill the traditional functions of money and be useful as a currency. To achieve this, controls are needed within the ecosystem of the cryptocurrency. Although a simulation cannot predict future currency rates or other variables exactly, it is argued that a model that simulates a range of challenging behavior can be a useful testbed for control schemes. To illustrate and explore this idea, an agent-based economic model was used to simulate the early period of a hypothetical cryptocurrency and test two control mechanisms. The results suggest that this approach may be fruitful and that it may be important to include more than just coin minting within the control scheme. An economic simulation model is likely to be a valuable tool in developing and regulating effective cryptocurrency systems

    Heavy Quarkonia Production in p+p Collisions from the PHENIX Experiment

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    Quarkonia provide a sensitive probe of the properties of the hot dense medium created in high energy heavy ion collisions. Hard scattering processes result in the production of heavy quark pairs that interact with the collision medium during hadronization. These in-medium interactions convey information about the fundamental properties of the medium itself and can be used to examine the modification of the QCD confining potential in the collision environment. Baseline measurements from p+p and d+Au collision systems are used to distinguish cold nuclear matter effects while measurements from heavy ion collision systems are used to quantify in-medium effects. The PHENIX experiment has the capability of detecting heavy quarkonia at 1.2<∣η∣<2.21.2<|\eta|<2.2 via the ÎŒ+Ό−\mu^+\mu^- decay channel and at ∣η∣<0.35|\eta|<0.35 via the e+e−e^+e^- decay channel. Recent runs have resulted in the collection of high statistics p+p data sets that provide an essential baseline reference for heavy ion measurements and allow for further critical evaluation of heavy quarkonia production mechanisms. The latest PHENIX results for the production of the J/ψJ/\psi in p+p collisions are presented and future prospects for ψâ€Č\psi', χc\chi_{c} and ΄\Upsilon measurements are discussed.Comment: 4 pages, 2 figures, Proceedings for Quark Matter 200
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