5,348 research outputs found

    The Impact of Past Performance on Expectations of Future Success: An Investigation of Australian Managers

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    Competition among firms for market share and differential advantage is at an all-time high [3]. Moreover, investment in research and development (R&D) is seen as a major strategy in attaining and maintaining any competitive edge [4]. Little is known, however, about how experiencing poor performance in R&D endeavors affects managers\u27 perceptions of future opportunities for success in his or her company. Do managers believe that success breeds success, while poor performance is an indication of continued problems in the future? Or do managers believe that poor past performance is unrelated to future performance? Additionally, are some individuals prone to experience feelings of loss of control, while other individuals believe that they can influence future outcomes? When considering the importance of R&D endeavors to competitive strategy, these questions deserve attention and constitute the focus for this paper

    Robust fixed order dynamic compensation for large space structure control

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    A simple formulation for designing fixed order dynamic compensators which are robust to both uncertainty at the plant input and structured uncertainty in the plant dynamics is presented. The emphasis is on designing low order compensators for systems of high order. The formulation is done in an output feedback setting which exploits an observer canonical form to represent the compensator dynamics. The formulation also precludes the use of direct feedback of the plant output. The main contribution lies in defining a method for penalizing the states of the plant and of the compensator, and for choosing the distribution on initial conditions so that the loop transfer matrix approximates that of a full state design. To improve robustness to parameter uncertainty, the formulation avoids the introduction of sensitivity states, which has led to complex formulations in earlier studies where only structured uncertainty has been considered

    A hydrodynamic study of a fast‐bed dual circulating fluidized bed for chemical looping combustion

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    This study explores the use of a dual interconnected circulating fluidized bed (CFB) for chemical looping combustion. This design can enhance gas–solid interactions, but it is difficult to control the solid transfer and circulation rates. With the use of a 1:1 scale cold-flow model, an investigation determining the hydrodynamic behavior of the dual CFB system has been conducted. The cold-flow system consists of two identical fast-bed risers, each with an internal diameter of 100 mm and a height of 7 m. The simplified cold-flow model is based on the chemical looping Pilot-Scale Advanced CO2 Capture Technology (PACT) facility at Cranfield. Here, we have determined the minimum fluidization and transport velocities, and we have assessed the solid density profiles, transport capacity, and potential for the dilution by air/N2 leakage into the CO2 stream exiting the fuel reactor. The experimental procedure uses two different bed materials, molochite (ceramic clay) and FE100 (iron particles), and it satisfies the dynamic scaling laws to model the bed inventory within the system. The results indicate that the two fast-bed risers share similar density and pressure profiles. Stable circulation can be achieved through pneumatic transport. The circulation rate of the system is flexible and can be adjusted by altering the fluidization velocity in the riser and by altering the bed inventory. The gas leakage from the loop seal to the cyclone was found to be sensitive to the bed height and fluidization velocity in the loop seal. However, by maintaining a loop-seal bed height above 600 mm during operation, the outlet stream remains undiluted

    Pressurised calcination-atmospheric carbonation of limestone for cyclic CO2 capture from flue gases

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    A study was carried out to investigate the CO2 capture performance of limestone under atmospheric carbonations following pressurised calcination. A series of tests was carried out to study the role of pressurised calcination using a fluidised bed reactor. In this investigation, calcination of limestone particles was carried out at three levels of pressure: 0.1 MPa, 0.5 MPa, and 1.0 MPa. After calcination, the capture performance of the calcined sorbent was tested at atmospheric pressure. As expected, the results indicate that the carbonation conversion of calcined sorbent decreases as the pressure is increased during calcination. Pressurised calcination requires higher temperatures and causes an increase in sorbent sintering, albeit that it would have the advantage of reducing equipment size as well as the compression energy necessary for CO2transport and storage, and an analysis has been provided to give an assessment of the potential benefits associated with such an option using process software.EPSR

    Beyond Options

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    Scholars and policymakers now debate reforms that would prevent a bankruptcy filing from being a moment that forces valuation of the firm, crystallization of claims against it, and elimination of junior stakeholders’ interest in future appreciation in firm value. These reforms have many names, ranging from Relative Priority to Redemption Option Value. Much of the debate centers on the extent to which reform would protect the non-bankruptcy options of junior stakeholders, or harm the non-bankruptcy options of senior lenders. We argue that this focus on options misplaced. Protecting options is neither necessary nor sufficient for advancing the goal of a well-functioning bankruptcy system. What is needed is a regime that cashes out the rights of junior stakeholders with minimal judicial involvement. To illustrate, we propose an “automatic bankruptcy procedure” that gives senior creditors an option to restructure the firm’s debt or sell its assets at any time after a contractual default. Under this procedure, restructuring occurs in bankruptcy, but sales do not. Sales are either subject to warrants (which give junior stakeholders a claim on future appreciation) or are subject to judicial appraisal (which forces senior lenders to compensate junior stakeholders if the sale price was too low). Our proposal can be seen as an effort to design a formalized restructuring procedure that borrows from traditional state law governing corporate-control transactions. We show that this procedure minimizes core problems of current law – fire sales that harm junior stakeholders, delay that harms senior lenders, and the uncertainties generated by judicial valuation, which are exploited by all parties

    Three Models of Legal Ethics

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    This article presents a picture of each of the three theoretical models—autonomy, socialist, and deontological—and indicates how they differ from one another in their application to some aspects of attorney-client confidentiality, one of the most hotly debated topics of professional ethics

    Three Models of Legal Ethics

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    This article presents a picture of each of the three theoretical models—autonomy, socialist, and deontological—and indicates how they differ from one another in their application to some aspects of attorney-client confidentiality, one of the most hotly debated topics of professional ethics

    Terminal Deoxynucleotidyl Transferase: The Story of A Misguided DNA Polymerase

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    Nearly every DNA polymerase characterized to date exclusively catalyzes the incorporation of mononucleotides into a growing primer using a DNA or RNA template as a guide to direct each incorporation event. There is, however, one unique DNA polymerase designated terminal deoxynucleotidyl transferase that performs DNA synthesis using only single-stranded DNA as the nucleic acid substrate. In this chapter, we review the biological role of this enigmatic DNA polymerase and the biochemical mechanism for its ability to perform DNA synthesis in the absence of a templating strand. We compare and contrast the molecular events for template-independent DNA synthesis catalyzed by terminal deoxynucleotidyl transferase with other well-characterized DNA polymerases that perform template-dependent synthesis. This includes a quantitative inspection of how terminal deoxynucleotidyl transferase binds DNA and dNTP substrates, the possible involvement of a conformational change that precedes phosphoryl transfer, and kinetic steps that are associated with the release of products. These enzymatic steps are discussed within the context of the available structures of terminal deoxynucleotidyl transferase in the presence of DNA or nucleotide substrate. In addition, we discuss the ability of proteins involved in replication and recombination to regulate the activity of the terminal deoxynucleotidyl transferase. Finally, the biomedical role of this specialized DNA polymerase is discussed focusing on its involvement in cancer development and its use in biomedical applications such as labeling DNA for detecting apoptosis

    Partnering with Parents: Promising Approaches to Improve Reunification Outcomes for Children in Foster Care

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    Family reunification is one of the central tenents of the child welfare system, yet research supporting effective practices to promote safe reunifications is limited. As a departure from previous initiatives, the Parent Partner (PP) program enlists as staff mothers and fathers who have experienced child removal, services, and reunification. This study examines outcomes for children served by the PP program. The experimental group includes 236 children whose parents were served by a Parent Partner and a matched comparison group of 55 children whose parents were served by the public child welfare agency in 2004, before the Parent Partner program was established. Cases were examined 12 months following case opening to determine reunification status. Results from the outcome study indicate that reunification may be more likely for children whose parents were served by Parent Partners. Although there are limitations to the data, findings from this study suggest that the Parent Partner model may hold promise as a child welfare intervention designed to support reunification

    A shrinking core model for steam hydration of CaO-based sorbents cycled for CO2 capture

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    Calcium looping is a developing CO2 capture technology. It is based on the reversible carbonation of CaO sorbent, which becomes less reactive upon cycling. One method of increasing the reactivity of unreactive sorbent is by hydration in the calcined (CaO) form. Here, sorbent has been subjected to repeated cycles of carbonation and calcination within a small fluidised bed reactor. Cycle numbers of 0 (i.e., one calcination), 2, 6 and 13 have been studied to generate sorbents that have been deactivated to different extents. Subsequently, the sorbent generated was subjected to steam hydration tests within a thermogravimetric analyser, using hydration temperatures of 473, 573 and 673 K. Sorbents that had been cycled less prior to hydration hydrated rapidly. However, the more cycled sorbents exhibited behaviour where the hydration conversion tended towards an asymptotic value, which is likely to be associated with pore blockage. This asymptotic value tended to be lower at higher hydration temperatures; however, the maximum rate of hydration was found to increase with increasing hydration temperature. A shrinking core model has been developed and applied to the data. It fits data from experiments that did not exhibit extensive pore blockage well, but fits data from experiments that exhibited pore blockage less well
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