5,841 research outputs found

    Human Resources Strategy: The Era of Our Ways

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    The purpose of this chapter is to discuss some of the main features and trends in human resources (HR) strategy. Inasmuch as people are among the most important resources available to firms, one could argue that HR strategy should be central to any debate about how firms achieve competitive advantage. But this ā€œpeople are our most important assetā€ argument is actually fairly hollow in light of the evidence. Far too many articles on HR start with this premise, but the reality is that organizations have historically not rested their fortunes on human resources. The HR function remains among the least influential in most organizations, and competitive strategies have not typically been based on the skills, capabilities, and behaviors of employees. In fact, as Snell, Youndt and Wright (1996:62) noted, in the past executives have typically tried to ā€œtake human resources out of the strategy equation--i.e., by substituting capital for labor where possible, and by designing hierarchical organizations that separate those who think from those who actually do the work.

    Zinc calixarene complexes for the ring opening polymerization of cyclic esters

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    Reaction of Zn(Cā‚†Fā‚…)ā‚‚Ā·toluene (two equivalents) with 1,3-dipropoxy-p-tert-butyl-calix[4]arene (LĀ¹Hā‚‚) led to the isolation of the complex [{Zn(Cā‚†Fā‚…)}ā‚‚LĀ¹] (1), whilst similar use of Zn(Me)ā‚‚ resulted in the known complex [{Zn(Me)}ā‚‚LĀ¹] (2). Treatment of LĀ¹Hā‚‚ with in situ prepared Zn{N(SiMeā‚ƒ)ā‚‚}ā‚‚ in refluxing toluene led to the isolation of the compound [(Na)ZnN(SiMeā‚ƒ)ā‚‚LĀ¹] (3). The stepwise reaction of LĀ¹Hā‚‚ and sodium hydride, followed by ZnClā‚‚ and finally NaN(SiMeā‚ƒ)ā‚‚ yielded the compound [Zn{N(SiMeā‚ƒ)ā‚‚}ā‚‚LĀ¹] (4). The reaction between three equivalents of Zn(Cā‚†Fā‚…)ā‚‚Ā·toluene and oxacalix[3]arene (LĀ²Hā‚ƒ) at room temperature formed the compound {[Zn(Cā‚†Fā‚…)]ā‚ƒLĀ²} (5); heating of 5 in acetonitrile caused the ring opening of the parent oxacalix[3]arene and rearrangement to afford the complex [(LĀ²)Znā‚†(Cā‚†Fā‚…)(R)(RH)OH]Ā·5MeCN R = Cā‚†Fā‚…CHā‚‚-(p-įµ—BuPhenolate-CHā‚‚OCHā‚‚ā€“)ā‚‚ā€“p-įµ—BuPhenolate-CHā‚‚Oā»)Ā³ā» (6). The molecular structures of the new complexes 1, 3 and 6, together with that of the known complex 2, whose solid state structure has not previously been reported, have been determined. Compounds 1, 3ā€“5 have been screened for the ring opening polymerization (ROP) of Īµ-caprolactone (Īµ-CL) and rac-lactide. Compounds featuring a Znā€“Cā‚†Fā‚… fragment were found to be poor ROP pre-catalysts as they did not react with benzyl alcohol to form an alkoxide. By contrast, compound 4, which contains a zinc silylamide linkage, was the most active of the zinc-based calix[4]arene compounds screened and was capable of ROP at ambient temperature with 65% conversion over 4 h

    The Stock of External Sovereign Debt: Can We Take the Data At ā€˜Face Valueā€™?

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    The stock of sovereign debt is typically measured at face value. This is a misleading indicator when debts are issued with different contractual forms. In this paper we construct a new measure of the stock of external sovereign debt for 100 developing countries from 1979 to 2006 that is invariant to contractual form, and illustrate five problems with debt stocks measured at face value. First, we show that correcting for differences in the contractual form of debt paints a very different quantitative, and in some cases also qualitative, picture of the stock of developing country external sovereign debt. Second, rankings of indebtedness across countries, which were historically used to define eligibility for debt forgiveness, are sometimes inverted once we correct for differences in contractual form. Third, the empirical performance of the benchmark quantitative model of sovereign debt deteriorates by between 40 to 70 percent once model-consistent measures of debt are used. Fourth, we show how the spread of aggregation clauses in debt contracts which award creditors voting power in proportion to the contractual face value may introduce inefficiencies into the process of restructuring sovereign debts. Fifth, we show how the use of contractual face values gives issuing countries the ability to manipulate their debt stock data, and illustrate the use of these techniques in practice.

    Corn Row Spacing Considerations

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    Corn row spacing and plant population have been the focus of many studies throughout the years in an effort to identify ways to increase yields and minimize production costs. Many studies have shown that there was a yield increase going from a 40-inch row spacing to a 30-inch row spacing. Studies had varying results when it comes to less than a 30-inch row spacing. In some cases, row spacing has had no effect on yield whereas others have seen anywhere from a 2-7% increase in yield by narrowing row spacing from the more common 30-inch

    Collaborate Construction of a New Legal Field

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    Augmented Adaptive Control of a Wind Turbine in the Presence of Structural Modes

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    Wind turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, potentially causing component fatigue and failure. Two key technology drivers for turbine manufacturers are increasing turbine up time and reducing maintenance costs. Since the trend in wind turbine design is towards larger, more flexible turbines with lower frequency structural modes, manufacturers will want to develop methods to operate in the presence of these modes. Accurate models of the dynamic characteristics of new wind turbines are often not available due to the complexity and expense of the modeling task, making wind turbines ideally suited to adaptive control. In this paper, we develop theory for adaptive control with rejection of disturbances in the presence of modes that inhibit the controller. We use this method to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine operating in Region 3. The objective of the adaptive pitch controller is to regulate generator speed, accommodate wind gusts, and reduce the interference of certain structural modes in feedback. The control objective is accomplished by collectively pitching the turbine blades. The adaptive pitch controller for Region 3 is compared in simulations with a baseline classical Proportional Integrator (PI) collective pitch controller

    Discovery of a Classic FR-II Broad Absorption Line Quasar from the FIRST Survey

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    We have discovered a remarkable quasar, FIRST J101614.3+520916, whose optical spectrum shows unambiguous broad absorption features while its double-lobed radio morphology and luminosity clearly indicate a classic Fanaroff-Riley Type II radio source. Its radio luminosity places it at the extreme of the recently established class of radio-loud broad absorption line quasars (Becker et al. 1997, 2000; Brotherton et al. 1998). Because of its hybrid nature, we speculate that FIRST J101614.3+520916 is a typical FR-II quasar which has been rejuvenated as a broad absorption line (BAL) quasar with a Compact Steep Spectrum core. The direction of the jet axis of FIRST J101614.3+520916 can be estimated from its radio structure and optical brightness, indicating that we are viewing the system at a viewing angle of > 40 degrees. The position angles of the radio jet and optical polarization are not well-aligned, differing by 20 to 30 degrees. When combined with the evidence presented by Becker et al. (2000) for a sample of 29 BAL quasars showing that at least some BAL quasars are viewed along the jet axis, the implication is that no preferred viewing orientation is necessary to observe BAL systems in a quasar's spectrum. This, and the probable young nature of compact steep spectrum sources, leads naturally to the alternate hypothesis that BALs are an early stage in the lives of quasars.Comment: 14 pages, 6 postscript figures; accepted for publication in the Astrophysical Journa

    Local BDNF Delivery to the Injured Cervical Spinal Cord using an Engineered Hydrogel Enhances Diaphragmatic Respiratory Function.

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    We developed an innovative biomaterial-based approach to repair the critical neural circuitry that controls diaphragm activation by locally delivering brain-derived neurotrophic factor (BDNF) to injured cervical spinal cord. BDNF can be used to restore respiratory function via a number of potential repair mechanisms; however, widespread BDNF biodistribution resulting from delivery methods such as systemic injection or lumbar puncture can lead to inefficient drug delivery and adverse side effects. As a viable alternative, we developed a novel hydrogel-based system loaded with polysaccharide-BDNF particles self-assembled by electrostatic interactions that can be safely implanted in the intrathecal space for achieving local BDNF delivery with controlled dosing and duration. Implantation of BDNF hydrogel after C4/C5 contusion-type spinal cord injury (SCI) in female rats robustly preserved diaphragm function, as assessed b

    Biodegradation of high-concentration isopropanol by a solvent-tolerant thermophile, Bacillus pallidus

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    The aerobic biodegradation of high-concentration, to 24 g l ā€“1 , 2-propanol (IPA) by a thermophilic isolate ST3, identified as Bacillus pallidus , was successfully carried out for the first time. This solvent-tolerant B. pallidus utilized IPA as the sole carbon source within a minimal salts medium. Cultivation was carried out in 100-ml shake flasks at 60Ā°C and compared with cultivation within a 1-l stirred tank reactor (STR). Specific growth rate () was about 0.2 hā€“1 for both systems, with a maximum cell density of 2.4 x 10 8 cells mlā€“1 obtained with STR cultivation. During exponential growth and stationary phase, IPA biodegradation rates were found to be 0.14 and 0.02 g l ā€“1hā€“1, respectively, in shake-flask experiments, whereas corresponding values of 0.09 and 0.018 g l ā€“1hā€“1 were achievable in the STR. Generation of acetone, the major intermediate in aerobic IPA biodegradation, was also monitored as an indicator of microbial IPA utilization. Acetone levels reached a maximum of 2.2ā€“2.3 g lā€“1 after 72 and 58 h for 100-ml and 1-l systems, respectively. Both IPA and acetone were completely removed from the medium following 160 and 175 h, respectively, during STR growth, although this was not demonstrated within shake-flask reactions. Growth of B. pallidus on acetone or IPA alone demonstrated that the maximum growth rate () obtainable was 0.247 hā€“1 at 4 g lā€“1 acetone and 0.202 hā€“1 at 8 g lā€“1 IPA within shake-flask cultivation. These results indicate the potential of the solvent-tolerant thermophile B. pallidus ST3 in the bioremediation of hot solvent-containing industrial waste streams
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