555 research outputs found
Monitoring for a Shift in a Process Covariance Matrix Using the Generalized Variance
The commonly recommended charts for monitoring the mean vector are affected by a shift in the covariance matrix. As in the univariate case, a chart for monitoring for a change in the covariance matrix should be examined first before examining the chart used to monitor for a change in the mean vector. One such chart is the one that plots the generalized sample variance lSl verses the sample number t. We propose to study charts based on the statistics V = l(n - 1) Σ₀-¹ Sl¹/̳p̳ and U = 1n (l (n-1) Σ₀-¹Sl¹/̳p̳), where n is the sample size and Σ₀ is the in-control value of the process covariance matrix Σ. In particular, we will study the Shewhart V and U charts supplemented with runs rules. Also, we examine the methods that are useful in studying the run length properties of the cumulative sum (CUSUM) U charts. Further, we will study the effect that estimating Σ₀ has on the performance of these charts. Guidance will be given for designing the Shewhart charts with runs rules with illustrative examples
The influence of high-quality early childhood education programs on at-risk children\u27s literacy and language development
This literature review addressed the impact that high-quality early childhood education programs have on at-risk children\u27s literacy and language development. The purpose of this review was to focus on the impact and benefits that high quality early childhood education programs have on the literacy and language development of at-risk young children, and the influence that the early childhood teachers, the early childhood classroom environment, and the early childhood classroom activities have on the literacy and language development of young children who may be at-risk of developing reading difficulties when they begin formal education.
The research concluded that at-risk children who attended a high-quality early childhood education program were better prepared to enter school than those children who don\u27t have that opportunity and are also less likely to need remedial services. Research for this review was obtained through professional articles and books about the impact and benefits of high-quality early childhood education programs
THE PERSONALIZATION-PRIVACY PARADOX EXPLORED THROUGH A PRIVACY CALCULUS MODEL AND HOFSTEDE’S MODEL OF CULTURAL DIMENSIONS
The Personalization-Privacy Paradox is a relevant issue for companies today, as it deals with the paradox of customers who on the one hand want to keep their personal data private, but on the other hand desire the personalization benefits that can be gained by giving up that privacy. Many studies in the past have observed the Personalization-Privacy Paradox, but not thoroughly through the lens of a privacy calculus model. This paper uses a privacy calculus model to examine the Personalization-Privacy Paradox using Hofstede’s Six Dimensions of Culture and examines the United States, Germany, and China as case studies of three different cultures. These three cultures all have a great deal of influence in the world and are world opinion leaders but have vast differences in cultural values and beliefs. This paper shows the importance for marketers, designers, and implementers of personalization services to understand diverse cultures and how their varied idioms, beliefs, and values affect how they will perceive benefits and costs of personalization services in their internal privacy calculus. The marked differences in cultural scores and how those cultural beliefs affect the perceptions of personalization and privacy demonstrate that companies looking to expand their services and applications into new markets cannot rely on universal approaches
Hybrid Field Oriented and Direct Torque Control for Sensorless BLDC Motors Used in Aerial Drones
In this study, a sensorless hybrid control scheme for brushless direct current (BLDC) motors for use in multirotor aerial vehicles is introduced. In such applications, the control scheme must satisfy high-performance demands for a wide range of rotor speeds and must be robust to motor parameter uncertainties and measurement noise. The proposed controller combines field-oriented control (FOC) and direct torque control (DTC) techniques to take benefit of the advantages offered by each of these techniques individually. Simulation results demonstrate the effectiveness of the proposed control scheme over a wide range of rotor speeds as well as good robustness against parameter uncertainties within -5to + 10% for inductance and -5to + 5% for resistance parameters. The proposed hybrid controller is robust also against noise in voltage and current measurements. In order to verify the results from simulation, the proposed hybrid controller is implemented in hardware using the TI C2000 Piccolo Launchpad and TI BOOSTXL-DRV8305EVM BoosterPack. Testing is done with a Bull Running motor typically used in aerial drones. Testing experiments demonstrate that the hybrid controller reduces the rotor speed ripple when compared to DTC while operating in steady-state mode and decreases the response time to desired speed changes when compared to FOC
Neutrino magnetohydrodynamics
A new neutrino magnetohydrodynamics (NMHD) model is formulated, where the
effects of the charged weak current on the electron-ion magnetohydrodynamic
fluid are taken into account. The model incorporates in a systematic way the
role of the Fermi neutrino weak force in magnetized plasmas. A fast
neutrino-driven short wavelengths instability associated with the magnetosonic
wave is derived. Such an instability should play a central role in strongly
magnetized plasma as occurs in supernovae, where dense neutrino beams also
exist. In addition, in the case of nonlinear or high frequency waves, the
neutrino coupling is shown to be responsible for breaking the frozen-in
magnetic field lines condition even in infinite conductivity plasmas.
Simplified and ideal NMHD assumptions were adopted and analyzed in detail
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Human-specific transcriptional regulation of CNS development genes by FOXP2.
The signalling pathways controlling both the evolution and development of language in the human brain remain unknown. So far, the transcription factor FOXP2 (forkhead box P2) is the only gene implicated in Mendelian forms of human speech and language dysfunction. It has been proposed that the amino acid composition in the human variant of FOXP2 has undergone accelerated evolution, and this two-amino-acid change occurred around the time of language emergence in humans. However, this remains controversial, and whether the acquisition of these amino acids in human FOXP2 has any functional consequence in human neurons remains untested. Here we demonstrate that these two human-specific amino acids alter FOXP2 function by conferring differential transcriptional regulation in vitro. We extend these observations in vivo to human and chimpanzee brain, and use network analysis to identify novel relationships among the differentially expressed genes. These data provide experimental support for the functional relevance of changes in FOXP2 that occur on the human lineage, highlighting specific pathways with direct consequences for human brain development and disease in the central nervous system (CNS). Because FOXP2 has an important role in speech and language in humans, the identified targets may have a critical function in the development and evolution of language circuitry in humans
Access to Nitrogen Heterocycles via Borrowing Hydrogen Catalysis
Nitrogen heterocycles are ubiquitous motifs which occur as the core structure of several alkaloid natural products exhibiting inherent biological activity against an array of bacteria, fungi, viruses, and cancer cell lines. These azacycles serve as key synthetic building blocks for medicinal chemists to access more structurally complex and diverse compounds with tunable biological properties. A synthetic approach to these valuable motifs employing intramolecular borrowing hydrogen catalysis has been developed. The utility of the developed chemistry will be applied to synthetic efforts towards the recently isolated Cylicomorphins A-E
The mPower Study, Parkinson Disease Mobile Data Collected Using Researchkit
Current measures of health and disease are often insensitive, episodic, and subjective. Further, these measures generally are not designed to provide meaningful feedback to individuals. The impact of high-resolution activity data collected from mobile phones is only beginning to be explored. Here we present data from mPower, a clinical observational study about Parkinson disease conducted purely through an iPhone app interface. The study interrogated aspects of this movement disorder through surveys and frequent sensor-based recordings from participants with and without Parkinson disease. Benefitting from large enrollment and repeated measurements on many individuals, these data may help establish baseline variability of real-world activity measurement collected via mobile phones, and ultimately may lead to quantification of the ebbs-and-flows of Parkinson symptoms. App source code for these data collection modules are available through an open source license for use in studies of other conditions. We hope that releasing data contributed by engaged research participants will seed a new community of analysts working collaboratively on understanding mobile health data to advance human health
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