Mutual Consistency Research Articles

Transforming data into knowledge—Process Informatics for combustion chemistry

The present frontier of combustion chemistry is the development of predictive reaction models, namely, chemical kinetics models capable of accurate numerical predictions with quantifiable uncertainties. While the usual factors like deficient knowledge of reaction pathways and insufficient accuracy of individual measurements and/or theoretical calculations impede progress, the key obstacle is the inconsistency of accumulating data and proliferating reaction mechanisms. Process Informatics introduces a new paradigm. It relies on three major components: proper organization of scientific data, availability of scientific tools for analysis and processing of these data, and engagement of the entire scientific community in the data collection and analysis. The proper infrastructure will enable a new form of scientific method by considering the entire content of information available, assessing and assuring mutual scientific consistency of the data, rigorously assessing data uncertainty, identifying problems with the available data, evaluating model predictability, suggesting new experimental and theoretical work with the highest possible impact, reaching community consensus, and merging the assembled data into new knowledge.

On the Meteorological Instruments and Observations Made during the 19th Century Exploration of the Canadian Northwest Passage

Meteorological records from about 30 British Navy ships that overwintered in the Canadian Arctic islands between 1818 and 1859 are the earliest detailed baseline of direct historical data in this region against which modern and future climate trends can be assessed. We describe the types of meteorological instruments and the observational methods employed aboard these ships. For measuring air temperatures, both mercurial and spirit thermometers were used. Observations of atmospheric pressure were made using marine and aneroid barometers. Wind direction and speed were also logged. The Royal Navy’s ordered and disciplined daily regime was well-suited to regular scientific observations. Individual instruments on most Navy ships were calibrated against established Royal Observatory standards before and after expeditions. Many recording officers commented on the relative unreliability of spirit thermometers below the freezing point of mercury. Little contemporary written evidence exists regarding absolute accuracy or precision of meteorological instruments taken to the Arctic, but some calibration data are available to assess typical instrument errors between 32° and −38°F (0° and −39°C). Our comparison of minimum daily temperatures from four overwintering ships in 1853 and 1854 shows very high correlation coefficients. The mutual consistency of these records implies good instrumental precision. Although the absolute accuracy of temperatures recorded below the freezing point of mercury is in doubt, those above this point are relatively accurate. Guidance on the preferred methods of observing and recording were codified in, for example, the Admiralty’s Manual of Scientific Enquiry (Herschel, 1851). Meteorological registers were regarded as official documents that were, as far as possible, required to be complete and no attempt was to be made to fill in missing data. The need to screen or cover instruments from both solar and terrestrial radiation was also recognized from the earliest expeditions. It was not until the 1850s that standardizing the exposure of thermometers was resolved through the introduction of louvered screens. This unique set of ships’ meteorological registers presents opportunities to investigate a variety of meteorological parameters for the Canadian High Arctic in the 19th century, allowing quantitative assessment of change relative to contemporary climate.

Probing the nonlinear structure of general relativity with black hole binaries

Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Space Antenna (LISA) and stellar mass binary black holes in the European Gravitational Wave Observatory (EGO) offer an unique opportunity to test the nonlinear structure of general relativity. For a binary composed of two nonspinning black holes, the nonlinear general relativistic effects depend only on the masses of the constituents. In a recent paper, we explored the possibility of a test to determine all the post-Newtonian coefficients in the gravitational wave phasing. However, mutual covariances dilute the effectiveness of such a test. In this paper, we propose a more powerful test in which the various post-Newtonian coefficients in the gravitational wave phasing are systematically measured by treating three of them as independent parameters and demanding their mutual consistency. LISA (EGO) will observe BBH inspirals with a signal-to-noise ratio of more than 1000 (100) and thereby test the self-consistency of each of the nine post-Newtonian coefficients that have so-far been computed, by measuring the lower order coefficients to a relative accuracy of ∼10-5 (respectively, ∼10-4) and the higher order coefficients to a relative accuracy in the range 10-4-0.1 (respectively, 10-3-1).

06/01714 Characterization and quantification of uncertainty in solid oxide fuel cell hybrid power plants: Subramanyan, K. and Diwekar, U. M. Journal of Power Sources, 2005, 142, (1–2), 103–116

The mineralogy of clay-rich mineral matter isolated from a range of Australian bituminous coals has been evaluated in quantitative terms from X-ray powder diffraction (XRD) patterns using a Rietveld-based data processing technique. The chemical composition of coal ash derived from this mineral matter has been calculated and compared to the directly determined composition of the ash prepared from the same coal samples. Although there are some minor differences due in part to uncertainty regarding the actual composition of several minerals, the compositions indicated by the two methods show a relatively high correlation, suggesting that the Rietveld technique provides mineralogical analyses that are consistent with independently determined chemical data. Comparison of the normalised clay mineral percentages from the Rietveld analysis to quantitative interpretations based on a peak intensities in glycolated and heat-treated oriented aggregates of the respective clay fractions also shows a high correlation, confirming mutual consistency of the two different mineralogical analysis methods. Such quantitative mineralogical data are significant to a range of coal exploration, mining and utilization activities, including seam correlation, material handling and ash and slag formation in combustion processes.

Mutual consistency between simulated and measured pressure drops in silica monoliths based on geometrical parameters obtained by three-dimensional laser scanning confocal microscope observations

The geometrical properties of co-continuous macroporous silica monoliths have been studied by laser scanning confocal microscopy (LSCM) and a comparison has been made with those obtained by conventional mercury intrusion method. Tetrahedral skeleton model (TMS), which mimics the gel skeleton shape of monoliths, was compared with real monoliths in terms of macropore and porosity using the geometrical parameters extracted from the LSCM observations. Liquid flow behavior through the macroporous silica monoliths was examined in comparison with those simulated using TSM, based on the geometrical properties obtained from LSCM observations. Heterogeneity in macropore topology and connectivity in pores and skeletons are suggested to contribute to the improvement of the model structure for macroporous monoliths.

The efficiency of crop recognition on ENVISAT ASAR images in two growing seasons

The aim of the presented project was to assess the efficiency of crop recognition based on microwave Advanced Synthetic Aperture Radar (ASAR) images acquired from ENVISAT-1. Investigations were conducted during two consecutive growing seasons, in 2003 and 2004. The agrometeorological conditions during the selected seasons differed markedly, which induced year-to-year variations regarding the relevant characteristics of crop canopy. Multitemporal series of ASAR alternating polarization images were used for crop differentiation. Classification was performed using a neural network classifier trained separately for each year. Field observations conducted in the western part of Poland supplied datasets for training, validation, and testing of the classifier. Despite some differences noted in the classifier performance on two datasets, the results obtained for 2003 and 2004 showed high mutual consistency.

Twisted boundary states and representation of generalized fusion algebra

The mutual consistency of boundary conditions twisted by an automorphism group G of the chiral algebra is studied for general modular invariants of rational conformal field theories. We show that a consistent set of twisted boundary states associated with any modular invariant realizes a non-negative integer matrix representation (NIM-rep) of the generalized fusion algebra, an extension of the fusion algebra by representations of the twisted chiral algebra associated with the automorphism group G. We check this result for several concrete cases. In particular, we find that two NIM-reps of the fusion algebra for su ( 3 ) k ( k = 3 , 5 ) are organized into a NIM-rep of the generalized fusion algebra for the charge-conjugation automorphism of su ( 3 ) k . We point out that the generalized fusion algebra is non-commutative if G is non-Abelian and provide some examples for G ≅ S 3 . Finally, we give an argument that the graph fusion algebra associated with simple current extensions coincides with the generalized fusion algebra for the extended chiral algebra, and thereby explain that the graph fusion algebra contains the fusion algebra of the extended theory as a subalgebra.

Demonstration of a genotype–phenotype correlation in the polymorphic color vision of a non‐callitrichine New World monkey, capuchin (Cebus apella)

Color-vision polymorphism in New World monkeys occurs because of an allelic polymorphism of the single-copy red-green middle-to-long-wavelength-sensitive (M/LWS) opsin gene on the X chromosome. Because color-vision types can readily be estimated from allelic types of the M/LWS opsin gene, this polymorphic system offers researchers an excellent opportunity to study the association between vision and behavior. As a prerequisite for such studies, genetically determined color-vision types must be concordant with phenotypes determined directly by behavioral criteria (e.g., by a color discrimination test). However, such correlations between genotypes and phenotypes have been studied only for callitrichine species. Using genetic, electrophysiological, and behavioral approaches, we evaluated the color vision of brown capuchin monkeys (Cebus apella), a representative non-callitrichine model animal for physiology and behavior. Two allelic M/LWS opsins-P545 and P530-were identified in the studied captive population. Females had one or both of the alleles, and males had either one. The retinal sensitivity in P530 dichromats was short-wave shifted relative to that in P545 dichromats, whereas that in P530/P545 trichromats was between the two groups. In a discrimination task using Ishihara pseudo-isochromatic plates, P530/P545 trichromats were successful in discriminating stimuli that P530 and P545 dichromats were unable to discriminate. In a food-search task, P530/P545 trichromats were able to locate red targets among green distracters as quickly as among white distracters, whereas both types of dichromats took longer. These results demonstrate the mutual consistency between genotypes and phenotypes of color vision, and provide a solid genetic basis on which the ecology and evolution of color vision can be investigated.

Improving Ecological Impact Assessment by Statistical Data Synthesis Using Process-Based Models

Summary Population dynamic modelling often entails parameterizing quite sophisticated biological and ecological mechanisms. For models of moderate mechanistic complexity, this has traditionally been done in an ad hoc manner, with different parameters being estimated independently. The point estimates so obtained are then used for model simulation, perhaps with some further ad hoc adjustment based on comparison with any available data on population dynamics. Quantitative assessments of model adequacy and prediction uncertainty are not easily made using this approach. As an alternative, the paper investigates the practical feasibility of fitting a moderately complex population dynamic model directly and simultaneously to all the data available for parameterization of the model, and to all available data on the population dynamics of the target animal. This alternative approach allows us to combine all available quantitative information on the target species, to assess the viability of the model, the mutual consistency of model and different sources of data and to estimate the uncertainties that are associated with model-based predictions. The target organism in this study is the freshwater amphipod Gammarus pulex (L.), which we model using a stage-structured population dynamic model, implemented via a set of delay differential equations describing the basic demography of the population. Target data include population dynamic data from two sites, information on basic physiological relationships and environmental temperature data. Fitting is performed by using a non-linear least squares approach supplemented with a bootstrapping method for avoiding small scale local minima in the least squares objective function. Variance estimation is performed by further bootstrapping. Interest in Gammarus pulex population dynamics in this case is primarily related to likely population level responses to chemical stressors, and for this we examine predicted ‘recovery times’ following exposure to a known toxicant.

Galactic Globular Cluster Relative Ages

We present accurate relative ages for a sample of 55 Galactic globular clusters. The ages have been obtained by measuring the difference between the horizontal branch and the turnoff in two internally photometrically homogeneous databases. The mutual consistency of the two data sets has been assessed by comparing the ages of 16 globular clusters in common between the two databases. We have also investigated the consistency of our relative age determination within the recent stellar model framework. All clusters with [Fe/H] -0.8 are ~1 Gyr younger than the most metal-poor ones, with a relatively small age dispersion, although the metal-rich sample is still too small to allow firmer conclusions. There is no correlation of the cluster age with the galactocentric distance. We briefly discuss the implication of these observational results for the formation history of the Galaxy.

Spin-glass theory for pedestrians

In these notes the main theoretical concepts and techniques in the field of mean-field spinglasses are reviewed in a compact and pedagogical way, for the benefit of the graduateand undergraduate student. One particular spin-glass model is analysed (thep-spin spherical model) by using three different approaches: thermodynamics, coveringpure states, overlaps, overlap distribution, replica symmetry breaking, and thestatic transition; dynamics, covering the generating functional method, generalizedLangevin equation, equations for the correlation and the response, the modecoupling approximation, and the dynamical transition; and finally complexity,covering the mean-field (Thouless–Anderson–Palmer) free energy, metastable states,entropy crisis, threshold energy, and saddles. Particular attention has been paidto the mutual consistency of the results obtained from the different methods.

Are secondary schools spending enough on books?

Evidence is provided to illustrate that the current level of spending on books by English secondary schools is low with regard to maintaining existing book stocks and that parental expenditure is not making up the shortfall. An analysis of the inspection regime suggests a tendency to emphasise information and communications technology (ICT) to the relative neglect of books. The authors also provide an empirical study at school level of the respective contribution of books, ICT and other inputs to both student performance and overall success in inspections. Its findings raise important questions about not only the efficiency of resource allocation but also the role and mutual consistency of the examination and inspection systems.

PVTx measurements for N 2O + CH 3F, N 2O + CH 2F 2, and N 2O + CHF 3 binary systems

Isochoric PVTx measurements have been performed for the binary system of nitrous oxide + CH 3F (R41), +CH 2F 2 (R32), and +CHF 3 (R23) using a new experimental set-up. The experiments covered both the two-phase region and the superheated vapor region and were performed within the temperature range 214–358 K and within a pressure range from 270 to 5600 kPa. Data have been collected for not less than four compositions for each system. The vapor–liquid equilibrium data were derived correlating the experimental data by means of the Carnahan–Starling–De Santis equation of state. The studied systems show a positive deviation from the Raoult's law. The results obtained were compared with the Burnett PVTx data. The two methods showed a mutual consistency within an acceptable margin of error. No other experimental PVTx data were found in the literature for these binary systems.

Polymorphic bytecode

We define compositional compilation as the ability to typecheck source code fragments in isolation, generate corresponding binaries,and link together fragments whose mutual assumptions are satisfied, without reinspecting the code. Even though compositional compilation is a highly desirable feature, in Java-like languages it can hardly be achieved. This is due to the fact that the bytecode generated for a fragment (say, a class) is not uniquely determined by its source code, but also depends on the compilation context.We propose a way to obtain compositional compilation for Java, by introducing a polymorphic form of bytecode containing type variables (ranging over class names) and equipped with a set of constraints involving type variables. Thus, polymorphic bytecode provides a representation for all the (standard) bytecode that can be obtained by replacing type variables with classes satisfying the associated constraints.We illustrate our proposal by developing a typing and a linking algorithm. The typing algorithm compiles a class in isolation generating the corresponding polymorphic bytecode fragment and constraints on the classes it depends on. The linking algorithm takes a collection of polymorphic bytecode fragments, checks their mutual consistency, and possibly simplifies and specializes them. In particular, linking a self-contained collection of fragments either fails, or produces standard bytecode (the same as would have been produced by standard compilation of all fragments).

Assessment of vapor pressure data of solid metal carbonyls

The vapor pressure data of solid metal carbonyls have been assessed and compiled using the “Oonk arc representation” (OAR), also called the “ln f representation”. A simple modification is proposed to the existing OAR called the “ modified Oonk arc representation” (MOAR), which aids in the visual representation of the vapor pressure data. The solid metal carbonyls chosen for these data assessment do not exhibit any disproportionation: chromium carbonyl (Cr(CO) 6), tungsten carbonyl (W(CO) 6), osmium carbonyl (Os 3(CO) 12), molybdenum carbonyl (Mo(CO) 6), rhenium carbonyl (Re 2(CO) 10), and manganese carbonyl (Mn(CO) 5) have been evaluated. The sublimation properties using the assessed data (Δ sub G ∘, Δ sub H ∘ and Δ sub C p , m ∘ ) of these compounds have been evaluated and a discussion on the mutual consistency of various data sets for each compound over a wide range of temperature is presented.

The Rationality of Automobile Seatbelt Usage: The Value of Statistical Life and Fatality Risk Beliefs

This article examines the rationality of seatbelt usage using an original data set of 465 adult respondents. People with high stated values of statistical life, who do not smoke, and who have risk beliefs that are highly elastic with respect to actual risks are more likely to use seatbelts, as economic theory predicts. Respondents' stated values of statistical life were similar on average to the value of life range of $2.2 million to $7.9 million computed from their revealed preferences for seatbelt usage, providing empirical support for the mutual consistency of these two approaches.

Statistical approaches on discriminating spatial variation of species diversity

This study applied statistical approaches to the discrimination of spatial variations between sites and between forest types in the upper area of the Liukuei Experimental Forest of Taiwan Forestry Research institute, Taiwan. The main purpose was to compare the effectiveness of various statistical approaches and then present the best strategy for discriminating the spatial variations of species diversity. The two methods used were (1) univariate methods by diversity measures, Shannon t-test, and (2) multivariate methods by cluster analysis, ordination by non-metric multi-dimensional scaling, and principal component analysis. The results by univariate methods indicate that diversity differences exist between sites and between forest types. Meanwhile, the natural forest has more diversity than the plantation, and the hardwood plantation has more diversity than the conifer plantation. The differences between forest types are very significant at the 100 significance level according to the Shannon t-test. The results indicate that univariate methods by diversity measures are a flexible way to reduce the complexity of ”species by sites” matrices into a single coefficient. The results of using multivariate methods indicate that cluster analysis and ordination by non-metric multi-dimensional scaling and principal component analysis are useful techniques for discriminating spatial variations. However, ordination by non-metric multi-dimensional scaling discriminates better than principal component analysis. in addition, ordination by non-metric multi-dimensional scaling is a more informative summary than cluster analysis, and the combination of both the analyses is more effective than either alone for the mutual consistency of representations. it is concluded that the most powerful tools for discriminating the spatial variations of species diversity are in the multivariate category. Among multivariate methods, ordination by non-metric multidimensional scaling is preferable, and its superimposition with cluster analysis is recommended in order to obtain more information regarding the relationship between sites and between forest types.

Comparison of microwave satellite humidity data and radiosonde profiles: A case study

This article documents a case study comparing radiosonde humidity data to Advanced Microwave Sounding Unit (AMSU) satellite humidity data. The study had two goals: first, to develop a robust method for such a comparison, and second, to check the quality and mutual consistency of radiosonde data, radiative transfer model, and AMSU data. The radiosonde data used are Vaisala RS80 data from the station Lindenberg of the German Weather Service (DWD), which have been subject to several corrections compared to the standard data processing. The radiative transfer model is the Atmospheric Radiative Transfer Simulator (ARTS), and the AMSU data are those of the satellites NOAA 15 and 16 for the time periods 2001 and 2002. The comparison was done in radiance space, using a radiative transfer model to simulate AMSU radiances from the radiosonde data. The overall agreement is very good, with radiance biases below 1.5 K and standard deviations below 2 K. The main source of “noise” in the comparison is atmospheric inhomogeneity on the 10‐km scale. While the radiosonde correction performed at Lindenberg significantly reduces the bias between simulated and measured AMSU radiance, there still remains a slope in the radiance difference. Possible reasons for this were investigated. Most likely, the radiosondes underestimate the relative humidity under extremely dry conditions, showing 0 %RH when the true value is 2–4 %RH.

Limiting Activity Coefficients by Comparative Tensimetry: 1-Propanol and 1-Butanol in Heptane and in Octane

Limiting activity coefficients ( ) of 1-propanol and 1-butanol in heptane and octane were determined at 10-K increments between 303 K and 343 K using a differential static cell equilibrium apparatus. The comparative tensimetric technique was employed because it is well suited for the systems and conditions examined. The new measurements supplement and extend previously released data for some lower 1-alkanol in n-alkanes we determined by the inert gas stripping. The sets of data obtained by the two different experimental techniques show good mutual consistency. The present data compare favorably also with other literature information, and their temperature trends are reasonably consistent with calorimetric data on limiting partial molar excess enthalpies.

Micro-phase separation of diblock–copolymer melts confined in a slit from simulation calculations—effect of coarse-graining scale

Two methods with different levels of coarse-graining are used to simulate microphase separation in diblock copolymer melts. The first uses Monte Carlo simulation (MC) based on particles and the second uses the cell-dynamical-system method (CDS) based on fluid elements. Results are presented for symmetric and asymmetric A– B diblock-copolymer melts ( f A =0.5, 0.4, 0.3 and 0.2) confined in a slit. Several microdomain morphologies are obtained. A lamella structure with alternate A- and B-rich layers appears for the symmetric case. Mesh-like, bi-continuous cylinder-like and dispersed sphere-like layers appear for asymmetric block copolymers with different compositions. Both methods of calculation give similar morphologies, indicating their mutual consistency. However, the calculation efficiency of CDS is remarkably higher, and it is therefore used to provide the pattern evolutions in time, the order-parameter distribution in real space, and the dynamic scattering function in Fourier space.