12 research outputs found

    PAN AIR: A computer program for predicting subsonic or supersonic linear potential flows about arbitrary configurations using a higher order panel method. Volume 2: User's manual (version 3.0)

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    A comprehensive description of user problem definition for the PAN AIR (Panel Aerodynamics) system is given. PAN AIR solves the 3-D linear integral equations of subsonic and supersonic flow. Influence coefficient methods are used which employ source and doublet panels as boundary surfaces. Both analysis and design boundary conditions can be used. This User's Manual describes the information needed to use the PAN AIR system. The structure and organization of PAN AIR are described, including the job control and module execution control languages for execution of the program system. The engineering input data are described, including the mathematical and physical modeling requirements. Version 3.0 strictly applies only to PAN AIR version 3.0. The major revisions include: (1) inputs and guidelines for the new FDP module (which calculates streamlines and offbody points); (2) nine new class 1 and class 2 boundary conditions to cover commonly used modeling practices, in particular the vorticity matching Kutta condition; (3) use of the CRAY solid state Storage Device (SSD); and (4) incorporation of errata and typo's together with additional explanation and guidelines

    Patterns of Development of Independent Oil Companies in Louisiana: an Exploratory Study Into the Strategic Changes of Growing Companies.

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    This study was conducted to gain additional knowledge about the process of change as entrepreneurships in the oil industry grow and develop. Thirty independent operators comprised the sample. The owner/manager of each firm was questioned at length about the growth of his company. Particular attention was given to identifying the relative stage of development of each firm. This was determined by analyzing the strategic characteristics identified in the literature as descriptive of stages of development. The evidence seriously questions the applicability of the stages of development model for these companies. The data strongly suggests that growth is a more gradual process along a continuum rather than through a few distinct stages of development. No precise, clear-cut distinctions were found that could be used to divide the sample companies into readily identifiable stages of growth. A cluster analysis indicated that there were at least seven distinct groups of firms within the sample, but only general patterns of growth could be ascertained between them. A tentative process model of growth was developed to explain these general patterns of growth found. Growth of the sample companies did not appear to be either time or size dependent because it was not possible to identify any particular age or size when changes in development would occur. This research also found that organization structure was a fairly good predictor of overall development among independent oil operators. All of the more developed firms exhibited well-developed organization structures. In summary, the evidence gathered by this study suggests that there are only general patterns of development among independent operators in the oil industry. These patterns cannot be equated to stages of development as described in the literature. The process of growth in this industry is apparently more complex than stages models suggest

    The Significance of Evidence-based Reasoning for Mathematics, Mathematics Education, Philosophy and the Natural Sciences

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    In this multi-disciplinary investigation we show how an evidence-based perspective of quantification---in terms of algorithmic verifiability and algorithmic computability---admits evidence-based definitions of well-definedness and effective computability, which yield two unarguably constructive interpretations of the first-order Peano Arithmetic PA---over the structure N of the natural numbers---that are complementary, not contradictory. The first yields the weak, standard, interpretation of PA over N, which is well-defined with respect to assignments of algorithmically verifiable Tarskian truth values to the formulas of PA under the interpretation. The second yields a strong, finitary, interpretation of PA over N, which is well-defined with respect to assignments of algorithmically computable Tarskian truth values to the formulas of PA under the interpretation. We situate our investigation within a broad analysis of quantification vis a vis: * Hilbert's epsilon-calculus * Goedel's omega-consistency * The Law of the Excluded Middle * Hilbert's omega-Rule * An Algorithmic omega-Rule * Gentzen's Rule of Infinite Induction * Rosser's Rule C * Markov's Principle * The Church-Turing Thesis * Aristotle's particularisation * Wittgenstein's perspective of constructive mathematics * An evidence-based perspective of quantification. By showing how these are formally inter-related, we highlight the fragility of both the persisting, theistic, classical/Platonic interpretation of quantification grounded in Hilbert's epsilon-calculus; and the persisting, atheistic, constructive/Intuitionistic interpretation of quantification rooted in Brouwer's belief that the Law of the Excluded Middle is non-finitary. We then consider some consequences for mathematics, mathematics education, philosophy, and the natural sciences, of an agnostic, evidence-based, finitary interpretation of quantification that challenges classical paradigms in all these disciplines

    Determination of Pesticide Residues in Orange Samples using Chromatographic Techniques coupled with High Resolution Mass Spectrometry

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    Τα φυτοφάρμακα χρησιμοποιούνται ευρέως στη σύγχρονη γεωργία παγκοσμίως, με σκοπό την αύξηση της αγροτικής παραγωγής και βελτίωση της ποιότητας των γεωργικών προϊόντων. Η μη σωστή χρήση τους όμως οδηγεί στη συσσώρευση υπολειμμάτων αυτών στα φυτά και δημιουργεί δυσμενείς επιπτώσεις στο περιβάλλον και στην ανθρώπινη υγεία. Το πορτοκάλι είναι ένα εσπεριδοειδές φρούτο με σημαντική θρεπτική αξία στη διατροφή του ανθρώπου και μεγάλη εμπορική αξία στο παγκόσμιο εμπόριο. Στην παρούσα εργασία πραγματοποιήθηκε αναπτυξη και επικύρωση μίας πολυϋπολειμματικής μεθόδου για τον προσδιορισμό καταλοίπων φυτοφαρμάκων σε νωπά πορτοκάλια. Πιο συγκεκριμένα, αναπτύχθηκε και εφαρμόστηκε μέθοδος προσδιορισμού φυτοφαρμάκων σε δείγματα πορτοκαλιών. Τα εκχυλίσματα που προέκυψαν από την προκατεργασία, αναλύθηκαν σε συστήματα υγροχρωματογραφίας αντίστροφης φάσης συζευγμένης με υβριδικό αναλυτή φασματομετρίας μάζας τύπου τετραπόλου χρόνου πτήσης (reversed-phase liquid chromatography quadrupole-time-of-flight mass spectrometry, RPLC-QTOF-MS) σε θετικό και αρνητικό ιοντισμό με πηγή ηλεκτροψεκασμού (electrospray ionization, ESI) και αεριοχρωματογραφίας συζευγμένης με υβριδικό αναλυτή φασματομετρίας μάζας τύπου τετραπόλου χρόνου πτήσης (gas chromatography quadrupole-time-of-flight mass spectrometry (GC-QTOF-MS) σε θετικό ιοντισμό με πηγή χημικού ιοντισμού ατμοσφαιρικής πίεσης (Atmospheric Pressure Chemical Ionization, APCI). H μέθοδος επικυρώθηκε και αξιολογήθηκαν τα χαρακτηριστικά ποιότητάς της σύμφωνα με την οδηγία της Ευρωπαϊκής Επιτροπής SANTE/11813/2017, ως προς τη γραμμικότητα, ορθότητα και πιστότητα. Προσδιορίσθηκαν τα όρια ανίχνευσης και ποσοτικοποίησης της μεθόδου και του οργάνου καθώς επίσης εκτιμήθηκε το φαινόμενο επίδρασης της μήτρας. Επιπλέον, δημιουργήθηκε μια ψηφιακή βιβλιοθήκη που περιείχε την πληροφορία για την σάρωση των αναλυτών με την μέθοδο GC-APCI-QTOF. 10 Ακόμα, εξετάστηκαν πορτοκάλια του εμπορίου για την ύπαρξη υπολειμμάτων φυτοφαρμάκων. Εκτιμήθηκε αν τα πορτοκάλια της αγοράς τηρούσαν την ισχύουσα νομοθεσία. Επίσης διερευνήθηκε η πιθανή κατανομή των συγκεντρώσεων των φυτοφαρμάκων στα διάφορα μέρη του πορτοκαλιού όπως η φλούδα, η σάρκα και ο χυμός. Συμπερασματικά, η φασματομετρία μάζας υψηλής διακριτικής ικανότητας μπορεί να χρησιμοποιηθεί στο πλαίσιο της ρουτίνας της ανάλυσης των φυτοφαρμάκων. Όσον αφορά τα κριτήρια απόδοσης της μεθόδου, η βέλτιστη γραμμικότητα για τους περισσότερους αναλύτες ελήφθη για θετικό ιονισμό με LC-ESI-QTOF. Όσον αφορά την πιστότητα, ο θετικός ιονισμός με LC-ESI-QTOF και GC-APCI-QTOF αποδείχθηκε ισοδύναμος. Αξίζει να σημειωθεί ότι τα όρια ποσοτικοποίησης της μεθόδου ήταν κάτω από τα ευρωπαϊκά ανώτατα όρια καταλοίπων για τους επικυρωμένους αναλύτες. Σε θετικό ιοντισμό με LC-ESI-QTOF για τους περισσότερους αναλύτες παρατηρήθηκε καταστολή του σήματος, ενώ με GC-APCI-QTOF παρατηρήθηκε ενίσχυση του σήματος. Στα δείγματα πορτοκαλιών του εμπορίου ανιχνεύθηκαν επτά κατάλοιπα φυτοφαρμάκων που ήταν κάτω από τα ανώτατα όρια καταλοίπων. Ωστόσο, κατάλοιπα φυτοφαρμάκου Pyriproxyfen ανιχνεύθηκαν σε οργανικά δείγματα. Μεγαλύτερες συγκεντρώσεις υπολειμμάτων φυτοφαρμάκων Chlorpyrifos ανιχνεύθηκαν στην φλούδα πορτοκαλιού.Pesticides are widely used worldwide due to modern agriculture, to increase agricultural production and improve the quality of agricultural products. Ιncorrect use of them leads to accumulation of residues in plants and adversely affects the environment and human health. Orange is a citrus fruit with an important nutritional value in human nutrition and a great commercial value in world trade. In this study, development and validation of a multi-residue method for the determination of pesticide residues in fresh oranges was achieved. More specifically, a method for the determination of pesticides in orange samples was developed and applied. The resulting extracts from the pretreatment were analyzed in systems of reversed phase liquid chromatography coupled to hybrid mass spectrometry analyzer of type quadrupole time of flight (RPLC-QTOF-MS) in positive and negative ionization with an electrospray source (ESI), and gas chromatography coupled to hybrid mass spectrometry analyzer of type quadrupole time of flight (GC-QTOF-MS) in positive ionization with a source of Atmospheric Pressure Chemical Ionization (APCI). The method was validated and its performance characteristics were evaluated, in accordance with the European Commission Directive SANTE / 11813/2017 on linearity, accuracy and precision while the limits of detection and quantification of the method and instrument were determined and matrix effect was estimated. In addition, a digital library was created which contained the information for scanning of the analytes using the GC-APCI-QTOF method. Moreover, commercial oranges were analysed for pesticide residues. We evaluated if the commercial oranges were in compliance with legislation. Potential distribution of pesticide concentrations in the different parts of oranges such as peel, flesh and juice for was also investigated. In conclusion, high resolution mass spectrometry can be used in the context of routine pesticide residues analysis. As far as the performance criteria of 8 the method is concerned, the optimum linearity for the most of the analytes was obtained for positive ionization with LC-ESI-QTOF. Concerning presicion, positive ionization with LC-ESI-QTOF and GC-APCI-QTOF proved to be equivalent. It is noteworthy that the LOQs of the method were below European MRLs for validated analytes. In positive ionization with LC-ESI-QTOF signal suppression for most of the analytes was observed, while signal enhancement was observed in GC-APCI-QTOF. In commercial orange samples, seven pesticide residues were detected that were below MRLs. However pesticide residues of Pyriproxyfen were detected on organic samples. Higher concentrations of pesticide residues of Chlorpyrifos were detected in the orange peel

    Proceedings of the Workshop on Change of Representation and Problem Reformulation

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    The proceedings of the third Workshop on Change of representation and Problem Reformulation is presented. In contrast to the first two workshops, this workshop was focused on analytic or knowledge-based approaches, as opposed to statistical or empirical approaches called 'constructive induction'. The organizing committee believes that there is a potential for combining analytic and inductive approaches at a future date. However, it became apparent at the previous two workshops that the communities pursuing these different approaches are currently interested in largely non-overlapping issues. The constructive induction community has been holding its own workshops, principally in conjunction with the machine learning conference. While this workshop is more focused on analytic approaches, the organizing committee has made an effort to include more application domains. We have greatly expanded from the origins in the machine learning community. Participants in this workshop come from the full spectrum of AI application domains including planning, qualitative physics, software engineering, knowledge representation, and machine learning

    A Study of Shale Gas Production and Its Supply Chain

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    Over the last few years, shale gas has become one of the most important energy sources in the United States, and advances in related technologies have led to an unprecedented economic boom in several parts of the country. On the other hand, the shale gas sector and its unique extraction technologies are still relatively young, and there are a number of concerns from the public about several aspects of the shale gas industry such as hydraulic fracturing, methane emission and waste management. The objective of this thesis is to present a comprehensive and objective study of shale gas and its entire supply chain, including the various material flows within it, in order to motivate safety, cost-savings and operational efficiency improvement. The study begins with an introduction to the basic background of the petroleum, natural gas and shale gas industry and goes on to describe the process of shale gas production and map its supply chain, starting with initial exploration to identify a potential drilling location and ending with the delivery of the natural gas to end-use customers. We present detailed flow of various materials and when possible, costs in the shale gas supply chain as a first step toward planning for its efficient operation. We also span a wide range of topics including environmental effects and safety, public health implications of unconventional gas extraction, the upgraded equipment and techniques to reduce environmental pollution, the use pattern of shale gas, fluctuations in its price, and its implications on sustainable energy. We end with a detailed case study of distributed power generation from Marcellus shale, and discuss how natural gas can play a key role in bridging the gap between coal/petroleum based energy and renewable energy. As a more reliable and cheaper alternative to renewable energy today, and as a more environmentally friendly alternative to other fossil fuels such as coal and petroleum, shale gas has the potential to be a solution to the energy gap in the near future

    The 1997 NASA Aerospace Battery Workshop

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    This document contains the proceedings of the 30th annual NASA Aerospace Battery Workshop, hosted by the Marshall Space Flight Center on November 18-20, 1997. The workshop was attended by scientists and engineers from various agencies of the U.S. Government, aerospace contractors, and battery manufacturers, as well as international participation in like kind from a number of countries around the world. The subjects covered included nickel-cadmium, nickel-hydrogen, nickel-metal hydride, lithium, lithium-ion, and silver-zinc technologies, as well as various aspects of nickel electrode design

    MODEL 9977 B(M)F-96 SAFETY ANALYSIS REPORT FOR PACKAGING

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    The Significance of Evidence-based Reasoning in Mathematics, Mathematics Education, Philosophy, and the Natural Sciences

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    In this multi-disciplinary investigation we show how an evidence-based perspective of quantification---in terms of algorithmic verifiability and algorithmic computability---admits evidence-based definitions of well-definedness and effective computability, which yield two unarguably constructive interpretations of the first-order Peano Arithmetic PA---over the structure N of the natural numbers---that are complementary, not contradictory. The first yields the weak, standard, interpretation of PA over N, which is well-defined with respect to assignments of algorithmically verifiable Tarskian truth values to the formulas of PA under the interpretation. The second yields a strong, finitary, interpretation of PA over N, which is well-defined with respect to assignments of algorithmically computable Tarskian truth values to the formulas of PA under the interpretation. We situate our investigation within a broad analysis of quantification vis a vis: * Hilbert's epsilon-calculus * Goedel's omega-consistency * The Law of the Excluded Middle * Hilbert's omega-Rule * An Algorithmic omega-Rule * Gentzen's Rule of Infinite Induction * Rosser's Rule C * Markov's Principle * The Church-Turing Thesis * Aristotle's particularisation * Wittgenstein's perspective of constructive mathematics * An evidence-based perspective of quantification. By showing how these are formally inter-related, we highlight the fragility of both the persisting, theistic, classical/Platonic interpretation of quantification grounded in Hilbert's epsilon-calculus; and the persisting, atheistic, constructive/Intuitionistic interpretation of quantification rooted in Brouwer's belief that the Law of the Excluded Middle is non-finitary. We then consider some consequences for mathematics, mathematics education, philosophy, and the natural sciences, of an agnostic, evidence-based, finitary interpretation of quantification that challenges classical paradigms in all these disciplines
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