A microprocessor-based table lookup approach for magnetic bearing linearization

An approach for producing a linear transfer characteristic between force command and force output of a magnetic bearing actuator without flux biasing is presented. The approach is microprocessor based and uses a table lookup to generate drive signals for the magnetic bearing power driver. An experimental test setup used to demonstrate the feasibility of the approach is described, and test results are presented. The test setup contains bearing elements similar to those used in a laboratory model annular momentum control device

Declining Discount Rates: Evidence from the UK

We estimate schedules of declining discount rates for cost benefit analysis in the UK. We highlight the importance of model selection for this task and hence for the evaluation of long-term investments, namely climate change prevention and nuclear build.long-run discounting, state-space models,regime-switching models, climate change policy,nuclear build

Discounting the distant future: How much does model selection affect the certainty equivalent rate?

Evaluating investments with long-term consequences using discount rates that decline with the time horizon, (Declining Discount Rates or DDRs) means that future welfare changes are of greater consequence in present value terms. Recent work in this area has turned towards operationalising the theory and establishing a schedule of DDRs for use in cost benefit analysis. Using US data we make the following points concerning this transition: i) model selection has important implications for operationalising a theory of DDRs that depends upon uncertainty; ii) misspecification testing naturally leads to employing models that account for changes in the interest rate generating mechanism. Lastly, we provide an analysis of the policy implications of DDRs in the context of climate change for the US and show that the use of a state space model can increase valuations by 150% compared to conventional constant discounting.long-run discounting, interest rate forecasting,interest rate forecasting, state-space models,regime-switching models, climate change policy

Quantum Corrections to Newton's Law

We present a new approach to quantum gravity starting from Feynman's formulation for the simplest example, that of a scalar field as the representative matter. We show that we extend his treatment to a calculable framework using resummation techniques already well-tested in other problems. Phenomenological consequences for Newton's law are described.Comment: 7 pages, 1 figure; improved fig., refs;improved discussion;more discussion; proo

The decay eta_c^prime -> eta_c pi pi

It is pointed out that the decay of the recently observed charmonium eta_c^prime resonance, eta_c^prime -> eta_c pi pi is simply related to the well studied decay psi^prime -> J/psi pi pi and can thus be used for absolute normalization of other decay modes of the eta_c^prime. The total rate of the discussed decay should be approximately three to four times the corresponding rate for the psi^prime$ resonance making the channel with charged pions the most probable exclusive decay mode of the eta_c^prime with the branching ratio in the range 5-10 %.Comment: 5 pages, references adde

Neutral top-pion and the rare top decays t→cliljt\to c l_{i} l_{j}

We study the rare top decays $t\to c l_{i} l_{j}(l=\tau,\mu,or e)$ in the framework of topcolor-assisted technicolor($TC2$) models. We find that the neutral top-pion $\pi_{t}^{0}$ can produce significant contributions to these processes via the flavor changing couplings $\pi_{t}^{0} \bar{t} c$ and $\pi_{t}^{0} l_{i} l_{j}$. For the $\pi_{t}^{0}$ mass $m_{\pi_{t}}=150 GeV$ and the parameter $\epsilon=0.08$, the branching ratio $Br$(t$\to c \tau \tau)$ can reach $7.1\times10^{-7}$. Taking into account the constraints of the present experimental limit of the process $\mu\to e \gamma$ on the free parameters of $TC2$ models, we find that the value of $Br$($t\to c \tau \mu$)$\approx$$Br$($t\to c \tau e$) is in the range of 1.8$\times10^{-10}\sim1.7\times10^{-8}$.Comment: To be published in Phys.

Various Measures of Socioeconomic Status as Predictors of Formal and Informal Home Literacy Environments

Individual differences in literacy during early childhood are important predictors of later reading ability (Sénéchal & LeFevre, 2002) and cognitive achievements (Downer & Pianta 2006). These differences in early literacy have been shown to be associated with various forms of literacy opportunities in the home, collectively known as the home literacy environment (HLE; Sénéchal & LeFevre, 2002). HLE includes both an informal aspect, which involves “those [activities] for which the primary goal is the message contained in the print,” and a formal aspect, which entails “those [activities] for which parent and child focus on the print” (Sénéchal & LeFevre, 2002, p. 1). Each aspect of HLE is correlated with different aspects of future literacy. HLE, however, does not exist in a vacuum; it is associated with multiple family-level variables, most notably socioeconomic status (SES). Like HLE, SES can be conceptualized in many ways. The researchers hypothesized that different aspects of SES would be differentially related to HLE, and that Informal HLE would be more strongly predicted by income-related measures, whereas Formal HLE would be more strongly predicted by education-related measures. To disentangle this complex association between SES and HLE, the researchers administered surveys to the parents of 393 preschool-aged children in Columbus to document their Informal HLE, Formal HLE, and multiple aspects of their SES, including income, income-to-needs ratio, and parental education. Multiple regression was used to predict Informal and Formal HLE from the various SES measures. Results indicated that income (β=.182, p=.010), income to needs ratio (β=.179, p=.014), and maternal education (β=.207, p=.013) are unique, significant predictors of Informal HLE. No measures of SES were significant predictors of Formal HLE. The results suggest that SES plays a role in Informal HLE, but also suggest that SES is not a catch-all predictor of HLE and that factors not explored in this study may predict both Informal and Formal HLE. Although the results do not fully support hypotheses, they suggest the existence of complex associations between SES and HLE that must be understood in order to develop initiatives that address the underlying causes of disparities in early childhood literacy.U.S. Department of EducationAcademic Major: PsychologyAcademic Major: Public Affair

Search for Low Mass Exotic mesonic structures. Part II: attempts to understand the experimental results

Our previous paper, part I of the same study, shows the different experimental spectra used to conclude on the genuine existence of narrow, weakly excited mesonic structures, having masses below and a little above the pion (M=139.56 MeV) mass. This work \cite{previous} was instigated by the observation, in the $\Sigma^{+}$ disintegration: $\Sigma^{+}\to$pP$^{0}$, P$^{0}\to\mu^{-}\mu^{+}$ \cite{park}, of a narrow range of dimuon masses. The authors conclude on the existence of a neutral intermediate state P$_{0}$, with a mass M=214.3 MeV $\pm$ 0.5 MeV. We present here some attempts to understand the possible nature of the structures observed in part I.Comment: 3 pages, 4 figures. Follows 0710.1796. Both replace arXiv:0707.1261 [nucl-ex

GaAs-based Self-Aligned Stripe Superluminescent Diodes Processed Normal to the Cleaved Facet

We demonstrate GaAs-based superluminescent diodes (SLDs) incorporating a window-like back facet in a self-aligned stripe. SLDs are realised with low spectral modulation depth (SMD) at high power spectral density, without application of anti-reflection coatings. Such application of a window-like facet reduces effective facet reflectivity in a broadband manner. We demonstrate 30mW output power in a narrow bandwidth with only 5% SMD, outline the design criteria for high power and low SMD, and describe the deviation from a linear dependence of SMD on output power as a result of Joule heating in SLDs under continuous wave current injection. Furthermore, SLDs processed normal to the facet demonstrate output powers as high as 20mW, offering improvements in beam quality, ease of packaging and use of real estate. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Irrigation water management under risk: an application to Cyprus

We provide empirical evidence that attitude towards risk is important when assessing the impact of conservation policies on production choices. We �first follow the approach used by Antle (1987) which enables �flexible estimation of the stochastic technology without ad hoc specifi�cation of risk preferences. In a second step, the impact of water quotas on farmer decisions can be solved, using risk aversion and technology parameter estimates. Application is made on a farm-level data-set from the agricultural region of Kiti in Cyprus