3,357 research outputs found

    A Software Process Engineering Course

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    Maturing software development organizations are beginning to identify a distinct role in the software team: Software Process Engineer. A software process engineer designs the software processes used by the organization. The software process includes the process content (identification of the roles, activities, and work products of the processes, along with specific techniques, tools, guidance, examples and other supporting information) and the lifecycle model (the ordering of and dependencies between software engineering activities and work products). A process engineer assembles a process from existing process components, choosing and tailoring components to provide the balance of agility and discipline necessary for their organization and projects. We have developed a graduate software engineering course to educate our students on the basic concepts of software process engineering. We use the OMG Software Process Engineering Metamodel and the IEEE Standard for Developing a Software Project Life Cycle Process as ways to model and compare process design alternatives and to provide mechanisms to assemble reusable process components into enactable processes. We use the Open Unified Process as an example process and we survey a wide range of techniques and methods that can be incorporated into a process. We use the Eclipse Process Framework Composer and associated process component libraries to assemble processes for specific projects. This paper describes the process engineering course and provides an informal assessment of the course effectiveness

    Weak Pion Production off the Nucleon

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    We develop a model for the weak pion production off the nucleon, which besides the Delta pole mechanism (weak excitation of the Δ(1232)\Delta(1232) resonance and its subsequent decay into NπN\pi), includes also some background terms required by chiral symmetry. We re-fit the C5A(q2)C_5^A(q^2) form factor to the flux averaged νμpμpπ+\nu_\mu p \to \mu^-p\pi^+ ANL q2q^2-differential cross section data, finding a substantially smaller contribution of the Delta pole mechanism than traditionally assumed in the literature. Within this scheme, we calculate several differential and integrated cross sections, including pion angular distributions, induced by neutrinos and antineutrinos and driven both by charged and neutral currents. In all cases we find that the background terms produce quite significant effects and that they lead to an overall improved description of the data, as compared to the case where only the Delta pole mechanism is considered. We also show that the interference between the Delta pole and the background terms produces parity-violating contributions to the pion angular differential cross section, which are intimately linked to TT-odd correlations in the contraction between the leptonic and hadronic tensors. However, these latter correlations do not imply a genuine violation of time reversal invariance because of the existence of strong final state interaction effects.Comment: Typos corrected; comments adde

    Engineering aspects of the selective acid leaching process for refining mixed nickel-cobalt hydroxide

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    The precipitation of mixed hydroxide is increasingly being considered as an intermediate step in the hydrometallurgical processing of nickel and cobalt. Producers currently receive roughly 75% of the value of the contained nickel and zero value for contained cobalt. In this paper, a new selective leach process for refining the mixed hydroxide is described that allows for recovery of the majority of the nickel as final metal product and realizes value for the cobalt. The features of the new process are compared with two other alternative routes (1) acid leaching followed by solvent extraction of the cobalt and (2) ammonia leaching followed by solvent extraction of the nickel. The outcomes of a process simulation for the selective acid leaching process are presented along with capital and operating cost estimates. The operating and capital costs of the process are estimated to ±50%. For the processing of 50,000 t-Ni/y in the form of MHP, the operating cost is estimated to be 93millionAUD(93 million AUD (0.87 per lb of Ni contained in MHP) and the capital cost as defined for this study is estimated to be 287millionAUD.Anew20yearplantprocessingMHPwouldhaveapaybackperiodoflessthan2years,anIRRofover60287 million AUD. A new 20 year plant processing MHP would have a payback period of less than 2 years, an IRR of over 60% and an NPV of greater than 1.5 billion AUD. Over 94% of the total value (nickel and cobalt) contained in the MHP is extracted by the new process

    A Web-based process and process models to find and deliver information to improve the quality of flight software

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    Aerospace systems demand high-quality software engineering processes to deliver high quality products. Although most aerospace organizations have high-quality processes, many of these processes fail to deliver to the engineer the organization\u27s wealth of information and experience - information and experience that can further contribute to the quality of software products and engineering processes. In this paper, we present an interactive, web-based process support tool that delivers the information in a flight software engineering process as well as associated standards, lessons learned, and background information. The tool is based on an underlying formal model of the software engineering process activities and artifacts. This underlying model provides a semantic basis for context-based search and for reasoning about the engineering process. The result is an information portal to search for and deliver process and project-specific information to support the development of flight software

    Advancing the time of ripeness of grapes by the application of methyl 2-(ureidooxy) propionate (a growth retardant)

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    Methyl 2-(ureidooxy) propionate (MUP), a plant growth retardant, hastened the ripening of grape berries of Vitis vinifera L. cultivars Mataro and Sultana by about 2 weeks and 1 week, respectively. The vines were sprayed with 0.1 % solution of MUP about halfway :through the first rapid growth phase of the fruit and again 2 weeks later. Terminal and lateral shoot growth was inhibited. Ripening of berries was advanced as measured by development of colour, and changes in titratable acid and reducing sugar content. The earlier ripening of the berries may have been due to hormonal changes but the advancement was much greater than that found previously with abscisic acid or ethylene applied during the slow growth stage of berry development.Die Beschleunigung des Reifezeitpunktes von Trauben durch die Anwendung vonMethyl-2-(ureidooxy)-Propionat, einen WachstumsdämpferMethyl-2-(ureidooxy)-Propionat (MUP), welches das Pflanzenwachstum verlangsamt, beschleunigte bei den Vitis-vinifera-Sorten Mataro und Sultana die Beerenreife um etwa 2 Wochen bzw. 1 Woche. Die Reben wurden etwa in der Mitte der ersten raschen Wachstumsphase der Beeren und ein weiteres Mal 2 Wochen später mit einer 0,1%igen MUP-Lösung besprüht. Das terminale und laterale Triebwachstum war gehemmt. Die Beerenreife war beschleunigt, wie die Entwicklung der Beerenfarbe und die Veränderungen im Gehalt an titrierbarer Säure und reduzierenden Zuckern zeigten. Die frühzeitigere Beerenreife könnte auf hormonale Veränderungen zurückgehen; allerdings war die Reife viel stärker beschleunigt als im Fall früherer Versuche, in denen während der langen Wachstumsphase der Beerenentwicklung Abscisinsäure oder Äthylen angewandt worden waren

    A simple method for demonstrating macroscopically the location of polyphenolic compounds in grape berries

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    Slices of berries of several varieties of Vitis vinifera were stained with HCl, vanillin-HCl or FeCl3 to demonstrate macroscopically that the bulk of the polyphenolic compounds occur in the skins, seeds and conducting tissue of grape berries at all stages of development.Eine einfache Methode zur makroskopischen Lokalisation polyphenolischer Verbindungen in WeinbeerenSchnitte von Beeren verschiedener Vitis vinifera-Sorten wurden mit HCl, Vanillin-HCl oder FeCl3 angefärbt, um makroskopisch zu zeigen, daß der Hauptanteil der polyphenolischen Verbindungen in allen Entwicklungsphasen in der Schale, den Samen und den Leitbündeln der Weinbeere lokalisiert ist

    Predicting the influence of a p2-symmetric substrate on molecular self-organization with an interaction-site model

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    An interaction-site model can a priori predict molecular selforganisation on a new substrate in Monte Carlo simulations. This is experimentally confirmed with scanning tunnelling microscopy on Fre´chet dendrons of a pentacontane template. Local and global ordering motifs, inclusion molecules and a rotated unit cell are correctly predicted

    The color dipole BFKL-Regge expansion: from DIS on protons to pions to rise of hadronic cross sections

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    As noticed by Fadin, Kuraev and Lipatov in 1975 incorporation of asymptotic freedom into the BFKL equation splits the QCD pomeron into a series of isolated poles in complex angular momentum plane. Following our earlier work on the proton structure function we explore the phenomenological consequences of the emerging BFKL-Regge factorized expansion for the small-xx structure function of the pion F2π(x,Q2)F_{2\pi}(x,Q^2). We calculate F2πF_{2\pi} in a small-xx region and find good agreement with the recent H1 determination of F2π(x,Q2)F_{2\pi}(x,Q^2). We also present the BFKL-Regge factorization based evaluation of the contribution from hard scattering to the observed rise of the NNNN, πN\pi N and real photo-absorption γN\gamma N and γπ\gamma \pi total cross sections.Comment: 12 pages Latex 2 PS figures, Revised version accepted for publication in Physics Letters

    Social-psychological and Structural Factors Influencing the Experience of Chronic Disease: A focus on Individuals with Severe Arthritis

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    In-depth personal interviews were conducted with 29 men and women with severe arthritis of the hip or knee. All respondents had been identified by medical experts as having demonstrable need for total joint arthroplasty, but in assessment in another study, had stated an unwillingness to consider the procedure. In interviews, we explored 1) current self reported health status and co-morbidities; 2) features and functions of the informal and formal support network; and 3) general orientations to aging, illness and independence, to examine the influence of these on participants' strategies for coping with severe arthritis and their views of treatment options. We present a multi-level model of the social-interactional and social-structural features of lives in which the experience of arthritis and responses to it are contextualized. Interviews reveal a complex set of experiences and responses: participants frequently reject the medicalization of their arthritis; they normalize the experience of functional decline (ie: they modify expectations to fit their capacity), or define it as age normative; they draw on a broad set of previous experiences from the lay health care system as well as from the formal medical care system to define an appropriate strategy of coping for the "here and now". The discussion focuses on the distinction between objectively assessed disease and subjectively experienced illness, and the implications of this distinction for medical practice.illness experience, lay perspectives, social context, decision-making, chronic illness, arthritis

    Modulating the Properties of Azulene‐Containing Polymers through Controlled Incorporation of Regioisomers

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    Two libraries of random conjugated polymers are presented that incorporate varying ratios of regioisomeric azulene units connected via the 5‐membered or 7‐membered ring in combination with bithiophene or fluorene comonomers. It is demonstrated that the optoelectronic and stimuli‐responsive properties of the materials can be systematically modulated by tuning the relative percentage of each azulene building block in the polymer backbone. Significantly, these materials exhibit stimuli‐responsive behavior in the solid state with spin‐coated thin films undergoing rapid and reversible color switching. Ultimately, this work introduces a new design strategy in which the optoelectronic properties of conjugated polymers can be modulated by varying only the regiochemistry of the constituent building blocks along a polymer chain
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