Search results for "methods"
showing 10 items of 4526 documents
B1(1)Π state of KCs: high-resolution spectroscopy and description of low-lying energy levels.
2012
The diode laser induced B(1)(1)Π → X(1)Σ(+) fluorescence spectra of the KCs molecule were recorded by Fourier-transform spectrometer with resolution of 0.03 cm(-1). Buffer gas Ar was used to facilitate appearance of rotation relaxation lines in the spectra, thus enlarging the B(1)(1)Π dataset, allowing one to determine the Λ-splitting constants and to reveal numerous local perturbations. A dataset was systematically obtained for B(1)(1)Π vibrational levels ν(') ∈ [0; 5] nonuniformly covering rotational levels with J(') ∈ [7; 233]. For ν(') ∈ [0; 3], the less-perturbed data of f-components were included in the fit. A pointwise potential energy curve (PEC) based on the inverted perturbation a…
Simultaneous determination of 4-nitroanisole, 4-nitrophenol, and 4-nitrocatechol by phase-sensitive ac polarography.
1977
Abstract Phase‐sensitive ac polarography was applied to the simultaneous quantitative determination of 4‐nitroanisole, 4‐nitrophenol and 4‐nitrocatechol in alkaline solutions. Certain experimental precautions are necessary to determine each compound in the presence of the other two. Thus, 4‐nitrocatechol is determined indirectly by forming a yellow ratio chelate with cupric ions, whereas 4‐nitroanisole is determined directly by the reduction waves of the nitro group. For the determination of 4‐nitrophenol, the interference by the simultaneously present 4‐nitrocatechol must be eliminated by masking it by the addition of magnesium ions. The method described permits a qualitative and quantitat…
An Overview of Assessment Practices
2016
On a global scale, attempts to specify conceptually academic learning outcomes have been made mostly in OECD countries. Definitions of learning outcomes can be used not only as an orientation for accrediting degree courses and universities; in some countries, they are used also as a basis for the development of assessment methods. The following will provide an overview of various key approaches and projects in this field.
Linear infrared dichroism by a double modulation technique
1991
In the first part of this paper an experimental setup using Fourier-transform infrared spectroscopy (FTIR) in combination with a photoelastic modulator (PEM) for linear dichroism measurements is described. The second part shows the influence of PEM-amplitude and scan-velocity on the sensitivity of the instrument. The third part deals with the fringe-problem in the baselines of absorbance spectra and its influence on the determination of the linear dichroic ratio.
A Monte Carlo Study of Knots in Long Double-Stranded DNA Chains.
2016
We determine knotting probabilities and typical sizes of knots in double-stranded DNA for chains of up to half a million base pairs with computer simulations of a coarse-grained bead-stick model: Single trefoil knots and composite knots which include at least one trefoil as a prime factor are shown to be common in DNA chains exceeding 250,000 base pairs, assuming physiologically relevant salt conditions. The analysis is motivated by the emergence of DNA nanopore sequencing technology, as knots are a potential cause of erroneous nucleotide reads in nanopore sequencing devices and may severely limit read lengths in the foreseeable future. Even though our coarse-grained model is only based on …
Polynomial Regression and Measurement Error
2020
Many of the phenomena of interest in information systems (IS) research are nonlinear, and it has consequently been recognized that by applying linear statistical models (e.g., linear regression), we may ignore important aspects of these phenomena. To address this issue, IS researchers are increasingly applying nonlinear models to their datasets. One popular analytical technique for the modeling and analysis of nonlinear relationships is polynomial regression, which in its simplest form fits a "U-shaped" curve to the data. However, the use of polynomial regression can be problematic when the independent variables are contaminated with measurement error, and the implications of error can be m…
Photo-z optimization for measurements of the BAO radial scale
2009
ArXiv pre-print avaible at:http://arxiv.org/abs/0812.3414
A cautionary note on the finite sample behavior of maximal reliability.
2019
Several calls have been made for replacing coefficient α with more contemporary model-based reliability coefficients in psychological research. Under the assumption of unidimensional measurement scales and independent measurement errors, two leading alternatives are composite reliability and maximal reliability. Of these two, the maximal reliability statistic, or equivalently Hancock's H, has received a significant amount of attention in recent years. The difference between composite reliability and maximal reliability is that the former is a reliability index for a scale mean (or unweighted sum), whereas the latter estimates the reliability of a scale score where indicators are weighted di…
The positioning system of the ANTARES Neutrino Telescope
2012
The ANTARES neutrino telescope, located 40km off the coast of Toulon in the Mediterranean Sea at a mooring depth of about 2475m, consists of twelve detection lines equipped typically with 25 storeys. Every storey carries three optical modules that detect Cherenkov light induced by charged secondary particles (typically muons) coming from neutrino interactions. As these lines are flexible structures fixed to the sea bed and held taut by a buoy, sea currents cause the lines to move and the storeys to rotate. The knowledge of the position of the optical modules with a precision better than 10cm is essential for a good reconstruction of particle tracks. In this paper the ANTARES positioning sys…
Newborns with an impairment: discourses of hospital staff.
2007
The birth of a baby with an impairment goes against dominant cultural ideals about a happy event. Therefore, the interaction between professionals and parents is particularly important, from the hospital maternity ward to the home. In this article, the author examines both the representations of neonatal impairments constructed by professionals and the consequent subject positions for these babies with impairments. The study is based on interview data collected among 19 staff members of one Finnish county hospital. The author analyzed the data by means of qualitative discourse analysis and concludes that it would be important for health care professionals to provide many-sided elements for…