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Deblurring is an ill-posed inverse problem naturally and becomes more complex if the noise is also tainting the image. Classical approaches of inverse filtering and linear algebraic restorations are now obsolete due to the additive noise, as the problem is very sensitive to the small perturbation in the data. To cater the sensitivity of solution for small perturbations, smoothness constraints are generally added in the classical approaches. Previously neural networks and gradient based approaches have widely been used for optimisation; however, due to improper regularisation and computational cost, the problem is still an active research problem. In this paper, a new simple, efficient and robust method of regularisation based on the difference of grey scale average of image and each element of the estimated image is proposed. Constrained least square error is considered for optimisation and gradient based steepest descent algorithm is designed to estimate the optimal solution for restoration iteratively. The visual results and statistical measures of the experiments are presented in the paper which shows the effectiveness of the approach as compared to the state of art and recently proposed techniques. [ABSTRACT FROM AUTHOR]

Highlights: [•] The scheduling model is used for the sizing of a pumped storage power plant. [•] All variables are interrelated in inter-temporal constraints, leading to a direct approach. [•] The decision vector is separated into past and future decisions. [•] The model can be immediately translated into a mathematical program modeling language. [•] Forecast errors are simulated as uncertainty cones of correlated time series of growing variance. [Copyright &y& Elsevier]

Spatial data mining is the process of discovering interesting patterns from large databases that are useful. Discovering interesting patterns from the spatial information is rather a challenging and complex task when compared to extraction from the traditional datasets. This paper gives an insight into various spatial clustering algorithms, their strengths and weaknesses, and focus on issues like quality measures. [ABSTRACT FROM AUTHOR]

In many applications, such as physiology and finance, large time series data bases are to be analyzed requiring the computation of linear, nonlinear and other measures. Such measures have been developed and implemented in commercial and freeware softwares rather selectively and independently. The Measures of Analysis of Time Series (MATS) MATLAB toolkit is designed to handle an arbitrary large set of scalar time series and compute a large variety of measures on them, allowing for the specification of varying measure parameters as well. The variety of options with added facilities for visualization of the results support different settings of time series analysis, such as the detection of dynamics changes in long data records, resampling (surrogate or bootstrap) tests for independence and linearity with various test statistics, and discrimination power of different measures and for different combinations of their parameters. The basic features of MATS are presented and the implemented measures are briefly described. The usefulness of MATS is illustrated on some empirical examples along with screenshots.

The new generation of short-read sequencing technologies requires reliable measures of data quality. Such measures are especially important for variant calling. However, in the particular case of SNP calling, a great number of false-positive SNPs may be obtained. One needs to distinguish putative SNPs from sequencing or other errors. We found that not only the probability of sequencing errors (i.e. the quality value) is important to distinguish an FP-SNP but also the conditional probability of "correcting" this error (the "second best call" probability, conditional on that of the first call). Surprisingly, around 80% of mismatches can be "corrected" with this second call. Another way to reduce the rate of FP-SNPs is to retrieve DNA motifs that seem to be prone to sequencing errors, and to attach a corresponding conditional quality value to these motifs. We have developed several measures to distinguish between sequence errors and candidate SNPs, based on a base call's nucleotide context and its mismatch type. In addition, we suggested a simple method to correct the majority of mismatches, based on conditional probability of their "second" best intensity call. We attach a corresponding second call confidence (quality value) of being corrected to each mismatch. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the proportion of ecologic studies published during a 20-year period regarding environmental exposures and cancer in which correlation coefficients or coefficients of determination were used as a measure of association. The authors performed a descriptive analysis of published literature by conducting a systematic review of PubMed to identify eligible ecologic studies published between 1991 and 2010. The reported measure of association was extracted for all eligible studies. During the 20-year study period, 35/105 (33%, 95% confidence limits [CL]: 25%, 43%) ecologic studies used correlation coefficients or coefficients of determination as a measure of association. These results indicate that the use of correlation coefficients and coefficients of determination as measures of association in ecologic studies of environmental exposures and cancer is relatively common, despite extensive literature discouraging their interpretation as valid measures of association. [ABSTRACT FROM PUBLISHER]

Abstract: The sunshine number is a Boolean random parameter stating whether the sun is covered or not by clouds. The first four statistical moments of the sunshine number are theoretically derived as a function of a single parameter, the cloud shade. Alternately, this single parameter may be the total cloud cover amount. These parameters are very often measured by the meteorological stations. Time series of global and diffuse solar irradiance recorded at 15-second time intervals between sunrise and sunset during all the days in 2009 in the Romanian town of Timisoara are used to validate the theory. In case of cloud shade representation, there is very good agreement between theory and measurements for all statistical indicators, for all summer and winter days analyzed here, which belong to various classes of cloud shade. In case of cloud cover amount representation, there is a good concordance between theory and measurements when the skewness is considered. In case of the variance and the kurtosis, the concordance is still reasonable. Three types of probability distributions for the sunshine number values have been defined. They were evaluated by using the existing sunshine number database and best fit analytical relationships have been obtained. [Copyright &y& Elsevier]

Various techniques of fitness landscape analysis for the determination of optimisation problem hardness for evolutionary algorithms are proposed in the literature. However, a few implementations of these techniques and their application in practice are described nowadays. In the paper comparative statistical and information analysis for benchmark fitness functions such as Sphere, Rastrigin, Rosenbrock and Ackley functions is performed. Both statistical and information measures for benchmark fitness landscapes are estimated and interpreted in the optimisation context. The sensitivity analysis is performed to determine how the conditions of experimental analysis and the noise factor will impact the target measures and their estimations. [ABSTRACT FROM AUTHOR]

As was the case in the beginning of the sequencing era, the new generation of short-read sequencing technologies still requires both accuracy of data processing methods and reliable measures of that accuracy. Inspired by the classic of the genre, the Phred method, we generalized those findings in the area of base quality value calibration. We introduce a simple, straightforward statistically established way to measure the performance of a calibrator, and to find an optimal way to assess its reliability. We illustrate the method by assessing the performance of several calibrators/predictors for Illumina, Genome Analyser 2 (GA2) data. The choice of the best predictor is based on optimization of validity, discriminative ability and discrimination power for several candidate predictors. We applied the method on data from one experimental run for genome of the phage ϕX, and found the best predictor out of ten candidates to be 'Purity', a statistics derived from corrected cluster intensities. The source code for the comparison of the predictors is available from the authors by request. [ABSTRACT FROM AUTHOR]

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This paper presents a text-mining approach in order to extract candidate terms from a corpus. The relevant candidates are selected using a web-mining approach. The terms (i.e. relevant candidate terms) we find are the instances of specialized ontologies built during this process. The experiments are based on real data -- Human Resources corpus -- and they show the quality of our text and web mining approaches. [ABSTRACT FROM AUTHOR]

Carbon Capture and Storage (CCS) is of interest to the scientific community as a way of achieving significant global reduction of atmospheric CO2 emission in the medium term. CO2 would be transported from large emission points (e.g. coal fired power plants) to storage sites by surface/shallow high pressure pipelines. Modelling of CO2 atmospheric dispersion after leakages from transportation facilities will be required before starting large scale CCS projects. This paper deals with the evaluation of the atmospheric dispersion CFD tool Fluidyn-PANACHE against Prairie Grass and Kit Fox field experiments. A description of the models for turbulence generation and dissipation used (k–ɛ and k–l) and a comparison with the Gaussian model ALOHA for both field experiments are also outlined. The main outcome of this work puts PANACHE among the “fit-for-purpose” models, respecting all the prerequisites stated by Hanna et al. [Hanna, S.R., Chang, J.C. and Strimaitis, D.G., 1993. Hazardous gas model evaluation with field observations. Atmospheric Environment, 27, 2265–2285] for the evaluation of atmospheric dispersion model performance. The average under-prediction has been ascribed to the usage of mean wind speed and direction, which is characteristic of all CFD models. The authors suggest a modification of performance ranges for model acceptability measures, within the field of high pressure CO2 transportation risk assessment, with the aim of accounting for the overall simplification induced by the usage of constant wind speed and direction within CFD atmospheric dispersion models. [Copyright &y& Elsevier]

Many statistical measures and algorithmic techniques have been proposed for studying residue coupling in protein families. Generally speaking, two residue positions are considered coupled if, in the sequence record, some of their amino acid type combinations are significantly more common than others. While the proposed approaches have proven useful in finding and describing coupling, a significant missing component is a formal probabilistic model that explicates and compactly represents the coupling, integrates information about sequence, structure, and function, and supports inferential procedures for analysis, diagnosis, and prediction. We present an approach to learning and using probabilistic graphical models of residue coupling (GMRCs). These models capture significant conservation and coupling constraints observable in a multiply aligned set of sequences. Our approach can place a structural prior on considered couplings, so that all identified relationships have direct mechanistic explanations. It can also incorporate information about functional classes, and thereby learn a differential graphical model that distinguishes constraints common to all classes from those unique to individual classes. Such differential models separately account for class-specific conservation and family- wide coupling, two different sources of sequence covariation. They are then able to perform interpretable functional classification of new sequences, explaining classification decisions in terms of the underlying conservation and coupling constraints. We apply our approach in studying both G protein-coupled receptors and PDZ domains, identifying and analyzing family-wide and class-specific constraints, and performing functional classification. The results demonstrate that GMRCs provide a powerful tool for uncovering, representing, and utilizing significant sequence-structure-function relationships in protein families. [ABSTRACT FROM PUBLISHER]

Abstract: In order to suggest a new methodology for selecting an appropriate dispersion model, various statistical measures having respective characteristics and recommended value ranges were integrated to produce a new single index by using fuzzy inference where eight statistical measures for various model results, including fractional bias (FB), normalized mean square error (NMSE), geometric bias mean (MG), geometric bias variance (VG), within a factor of two (FAC2), index of agreement (IOA), unpaired accuracy of the peak concentration (UAPC), and mean relative error (MRE), were taken as premise part variables. The new methodology using a single index was applied to the prediction of ground-level SO2 concentration of 1-h average in coastal areas, where eight modeling combinations were organized with fumigation models, σy schemes for pre-fumigation, and modification schemes for σy during fumigation. As a result, the fumigation model of Lyons and Cole was found to have better predictability than the modified Gaussian model assuming that whole plume is immerged into the Thermal Internal Boundary Layer (TIBL). Again, a better scheme of σy (fumigation) was discerned. This approach, which employed the new integrated index, appears to be applicable to model evaluation or selection in various areas including complex coastal areas. [Copyright &y& Elsevier]

Abstract: A comprehensive model evaluation has been conducted for MM5-CMAQ for the period of 1–10 July 1999 of the Southern Oxidants Study episode with a coarse-grid horizontal spacing of 32-km and a nested fine-grid spacing of 8-km. Meteorological and chemical predictions from simulations with both grids are compared with observations from both routine monitoring networks (e.g., CASTNet, IMPROVE, and AIRS-AQS) and special studies (e.g., SOS99/SOS99NASH, SEARCH, and ARIES). In this Part I paper, five simulated meteorological variables (i.e., temperature, relative humidity (RH), wind speed, wind direction, and planetary boundary layer (PBL) height) are evaluated. While MM5 reproduces well the diurnal variations for temperature and RH, and the minimum temperatures at all sites, it tends to overpredict maximum temperatures and underpredict both maximum and minimum RHs on most days at most sites. MM5 predictions agree reasonably well for wind speeds but poorly for wind direction and the maximum mixing depths. The significant overpredictions in the PBL heights can be attributed to the positive biases of the maximum 2-m temperatures and to the Medium Range Forecast (MRF) model PBL scheme and the Oregon State University (OSU)-Land Surface Model used in the MM5 simulations. For wind speed/direction and the U- and V-component of the wind speed, the normalized mean bias (NMB) and the normalized mean bias factor (NMBF) are the most robust statistical measures because of the dominance of the extremely small observed values in the normalization for those variables. [Copyright &y& Elsevier]

Abstract: To find an easy-to-use, automated tool to identify technical vocabulary applicable to learners at various levels, nine statistical measures were applied to the 7.3-million-word ‘commerce and finance’ component of the British National Corpus. The resulting word lists showed that each statistical measure extracted a different level of specialized vocabulary as measured by word length, vocabulary level, US native speaker grade level, and Japanese school textbook vocabulary coverage, and that these measures produced level-specific words; i.e., beginning-level basic business words were identified using Cosine and the complimentary similarity measure; intermediate-level business words were extracted using log-likelihood, the chi-square test, and the chi-square test with Yates’s correction; and advanced-level business word lists were created using mutual information and McNemar’s test. We conclude that these statistical measures are effective tools for identifying multi-level specialized vocabulary for pedagogical purposes. [Copyright &y& Elsevier]

Statistical measures of bending moment capacity of titanium pipes exposed to high external pressure differences are developed. Variations in relevant geometry and material parameters are found from laboratory tests. These quantities are input to non-linear finite element shell models of the pipe. Maximum bending moment capacities estimated by the non-linear finite element analyses are compared with some experimental results. A response surface approach is applied in order to reduce the required number of non-linear shell analyses. The bending moment capacity is expressed as a function of the basic parameter. With statistical distributions fitted to the uncertain input parameters, the response surface enables estimation of probability distributions for the bending moment capacity for a titanium pipe subjected to high external pressure. [Copyright &y& Elsevier]

Measuring the proportionality of outcomes in terms of each party's vote and seat shares is an important task in electoral analysis. Various indexes have been designed that provide a summary statistic of electoral proportionality/disproportionality. Claims and counter-claims have been made regarding the strengths and weaknesses of particular indexes. Important consequences follow from this methodological pluralism. First, it is not always clear which index has been employed when particular electoral outcomes are discussed. Second, recent additions to the list of indexes have not been thoroughly scrutinised and appraised. Third, the lack of knowledge about the general relationship between indexes means that observations might be different had a different index been used. This article seeks to identify and clarify the particular properties of different indexes of proportionality. Relatively new, and largely untested, indexes of proportionality are examined and some unusual and potentially damaging properties are identified. We also compare different measures of disproportionality in an effort to specify some general properties of the inter-relationships between them. Understanding the particular patterns of electoral competition and vote distributions that affect the relationship between these measures should enable users to anticipate the consequences of preferring one index over others. [ABSTRACT FROM AUTHOR]

Describes methods for examination of the relationship between two variables measured on a set of objects, using correlation coefficients and simple regression analysis. [ABSTRACT FROM AUTHOR]

The magnetoencephalography (MEG) signal was recorded while subjects watched a video containing separate blocks of affective and cognitive advertisements and recalled slides extracted from the video a day later. An earlier behavioural study using the same video material showed that the affective advertisements were better recalled and that administration of propranolol (a beta-adrenergic blocker) abolished this effect. Magnetic field tomography (MFT) was used to extract tomographic estimates of activity millisecond by millisecond from the continuous MEG signal. Statistically significant differences between affective and cognitive blocks were identified in posterior and prefrontal areas. Cognitive blocks produced stronger activity in posterior parietal areas and superior prefrontal cortex in all three subjects. Affective blocks modulated activity in orbitofrontal and retrosplenial cortex, amygdala and brainstem. Individual contributions to the statistical maps were traced in real time from milliseconds to many seconds. Time-locked responses from the recall session were used to compare average and single trial MFT solutions and to combine activations from all subjects into a common anatomical space. The last step produced statistically significant increases in occipital and inferior ventral cortex between 100 and 200 ms compared to a prestimulus baseline. [ABSTRACT FROM AUTHOR]

Describes the application of correlation and regression in food science and nutrition studies. [ABSTRACT FROM AUTHOR]

Speech processing and recognition are some of the imperative research areas, remarkably in user authentication and entertainment. There are assorted well-known approaches in the domain, and the properties of pitch are broadly used in most of the works. The objective of this work is to explore the capabilities of statistical features of the pitch in the gender identification problem. We proposed an effective combination of features, PFG-Pitch Feature for Gender, for gender identification with machine learning algorithms. The feature sets from three datasets – TIMIT, CHAINS and SLR-63- were used in the experiments. We could attain the maximum output in some ideal situations with the classical learning methods- CNN, MLP, SVM and LR. It is renowned that the outstanding performance from most of the machine learning classifiers embassies the magnitude of statistical features in speech processing. [ABSTRACT FROM AUTHOR]

In an earlier experiment, we have used the BTi twin MAGNES system (2 × 37 channels) to record the evoked magnetic field from five healthy right-handed male volunteers using two tasks: visual recognition of complex objects including faces and facial expressions of emotion. We have repeated the experiment with one of the five subjects using the BTi whole head system (148 channels). Magnetic field tomography (MFT) was used to extract 3D estimates of brain activity millisecond by millisecond from the recorded magnetoencephalographic (MEG) signals. Results from the MFT analysis of the average signals of the five subjects have been reported elsewhere (Streit et al. 1997; Streit et al. 1999). In this paper, we present results of the detailed single trial analysis for the subject recorded from the whole head system. We found activations in areas extending from the occipital pole to anterior areas. Regions of interest (ROIs) were defined entirely on functional criteria and confirmed independently by the location of the maximum activity on the MRI. Activation curves for each ROI were computed and objective statistical measures (Kolmogorov-Smirnov test) were then used to identify time segments for which the ROI activity showed significant differences both within the same and across different object/emotion categories. Emphasis is placed on the quantification of the activity from two ROIs, fusiform gyrus (FG) and amygdala (AM), which have been best studied in the context of processing of faces and facial expressions of emotion, respectively. We found no face-specific area as such, but instead areas like the FG was activated by all complex objects at roughly similar latencies and varying strengths. The amygdala activity was significantly different between 150 and 180 ms for fearful expression, and even earlier for happy expression. [ABSTRACT FROM AUTHOR]

A model of a real-time intrusion-detection expert system capable of detecting break-ins, penetrations, and other forms of computer abuse is described. The model is based on the hypothesis that security violations can be detected by monitoring a system's audit records for abnormal patterns of system usage. The model includes profiles for representing the behavior of subjects with respect to objects in terms of metrics and statistical models, and rules for acquiring knowledge about this behavior from audit records and for detecting anomalous behavior. The model is independent of any particular system, application environment, system vulnerability, or type of intrusion, thereby providing a framework for a general-purpose intrusion-detection expert system. [ABSTRACT FROM AUTHOR]

Objectives An examination of the methods used in assessing cancer detection rates in double reading studies to obtain a clear interpretation of the disparate results from differing studies. Setting National breast screening programmes. Methods Critical appraisal of methodologies used in the comparison of cancer detection rates with single or double reading. Results The reported improvement in cancer detection rate with double reading varies greatly between studies, depending upon whether the study is blinded and the statistic used. A method of calculating the increase in cancer detection rate due to a second reader is proposed. [ABSTRACT FROM AUTHOR]

Experiments are reported in which changes in the appearance of carpet samples after treatment ranging from 2 × 104 to 20 × 104 revolutions in a Tetrapod Walker were assessed with the aid of photographs of the new and treated samples. It was found that photographs, taken under controlled conditions, can be used as a record and basis for the assessment of changes in appearance resulting mainly from changes in texture, without much disturbing effect from colour and pattern. The ranking of carpets, based on changes in their appearance, did not alter significantly after 5 × 104 revolutions in the Tetrapod Walker. Results from the Tetrapod Walker are compared with those from a floor trial, where the effects of soiling caused further interference with the assessment. [ABSTRACT FROM AUTHOR]

Certain aspects of the handle of fabric laminates are related to properties of the component fabrics. Particular attention is paid to a theoretical prediction of the bending stiffness of a laminate from the bending and tensile properties of its components. This theoretical stiffness is a minimum value; if, in practice, the observed stiffness is much greater than this, it may generally be assumed that excess of adhesive or of melted foam is the cause. The paper also reports work on other features of the bending behaviour, such as the degree of recovery from bending, and on the shearing behaviour. The work is concluded by a brief study of some faulty laminates. [ABSTRACT FROM AUTHOR]

A method for measuring the variance between ultra-short lengths of yarn is presented and shows that the reported flattening of the B(L) curve to a constant value in the 5(0) region does not occur at lengths of down to at least 0-1 cm. The curve continues to rise logarithmically as the length decreases, possibly as far as 0· 045 cm, though detection imperfections render readings at this length open to some doubt. Yarn irregularity is shown to be strongly dependent on fibre length and on yarn fineness, particularly at short test lengths, and the possibility of periodicities at less than 1-cm ‘wavelengths’ is shown to exist. [ABSTRACT FROM AUTHOR]

Descriptions are given, together with fibre-length and fibre-diameter measurements, of the fibres in some raw-wool and cloth remains of early-nineteenth-century date from some Maori caves in the South Island of New Zealand. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about the measurement of the mean diameter of a blend of wool fibers through using the mean diameter of each component of the blend.

A study is reported in which fibre-length measurements were made on fibres withdrawn from a range of staples representing 21 sale lots of merino wool. The average variance of fibres within staples was 2.2 cm², and the estimates fell in the range 1.2–4.8 cm². Fibre-length variances within sale lots were estimated for six sale lots, and these ranged from 3.3 to 5.8 cm². Both the ratio of average fibre length to staple length and the regression coefficients for these parameters varied over a wide range (e.g., from 1.1 to 1.6 for the ratios and from 0.4 to 1.0 for the regression coefficients). This variation, coupled with relatively low correlation coefficients, indicates that the use of staple length as a predictor of the average fibre length of greasy wool is inefficient. However, staple length may be a useful predictor of the average fibre length of wool tops. [ABSTRACT FROM AUTHOR]

Estimates are reported for the variance of staple length within bales for each of 33 bales taken from separate sale lots of skirted classed merino wool. These variances range from 0.59 to 2.90 cm², with an average of 1.53 cm². Variances between bales, within sale lots of merino wool, were small and not significant. Within-bale variances for comeback and crossbred fleece ranged from 0.61 to 4.62 cm², with an average of 2.64 cm². The highest variances occurred within lots of broken and pieces, these ranging from 1.83 to 6.33, with an average of 3.44 cm². Evidence is presented which suggests that the removal of short wool during skirting makes the largest contribution to staple-length uniformity, classing having a secondary effect. Of the variation occurring within a bale, about half is found within fleeces and half between fleeces. [ABSTRACT FROM AUTHOR]

A factorial experiment performed on the aqueous compression-jet scour with three independent variables is reported. These variables were the feed-rate of greasy wool, the speed of the layer of wool, and the jetting pressures. The wools were processed to gilled slivers, on which mean-fibre-length determinations were made. The effects of the independent variables on the dependent variables of residual grease and dirt and mean fibre length (the last-named being a measure of the degree of entanglement of the scoured wool) were evaluated. The results obtained indicated the operating conditions to be used to achieve the optimum production capacity. [ABSTRACT FROM AUTHOR]

The article presents a letter to the editor concerning the variability of yield and fineness in length samples taken from bales of greasy wool.

A simple rapid method developed for the quantitative estimation of the various constituents of fleece wools is reported. The method is primarily based on visual estimations of the fibre qualities and the dirt and vegetable-matter contents of the fleece wools. These visual estimates are then related to significant correlations found to exist for a large number of fleece wools so that the average contents of the various remaining constituents may be rapidly estimated. This method of estimating the contents of the various constituents in fleece wools is especially useful in the scouring of raw wool, Where strict emphasis is being placed on efficiency and economy of operation, since it is possible to determine the optimum conditions of raw-wool feed-rate, detergent consumption, liquor back-flow, etc., to employ in a given wool-scouring machine from such estimates. It was found that the cumulative sum of the naturally occurring grease, suint, and moisture constituents deviates only slightly from a value of about 30% of the fleece weight, independently of the origin of the wool fleece. Since the remaining 70% of the fleece weight is composed of the dry-fibre, dirt, and vegetable-matter constituents, then only variations in the two last-named components will significantly affect the yield of a fleece. The best correlation found to exist was between the methanol-soluble matter in wool grease and the wool-grease content. It demonstrated that the highest contents of oxidized grease will be found in fleeces having the highest grease contents, whereas the actual oxidized fraction of the grease is generally lowest in these wools. [ABSTRACT FROM AUTHOR]

A study is reported of the variability of yield and fineness measurements between core samples within 'unclassed' lots of Australian greasy wool. The lots taken as 'unclassed' are some consigned from the farm for bulk-classing. The variability is compared with that found in previous studies, for auction lots that had been classed. The results are discussed from the point of view of obtaining an adequate sample from lots of unclassed wool, and a comment is made on the effectiveness of wool-classing as it appears from the comparison. [ABSTRACT FROM AUTHOR]

An account is given of an investigation in which air-flow measurements of fineness were made on individual core samples drawn from lots of scoured wool. From analyses of variance, estimates were made of between-bales, between-ends, and between-cores components of variance. These estimates suggest that the sampling precision (95 % confidence level) for lots of ten bales or more should be, at the worst, ±0-2 µm and may be better than ±0-1 µm for a sample consisting of two cores from each bale. An example is given in which the variability of fineness within a lot of greasy wool is compared with the variability within the same lot after it had been scoured and rebaled. [ABSTRACT FROM AUTHOR]

Previous papers have described the use of the cloth-bending-hysteresis test in investigating the detailed bending behaviour of fabrics. An account is given in this paper of the use of the techniques of regression analysis to investigate the correlation between the results of this test and other mechanical tests with subjective assessments of cloth stiffness and liveliness for two groups of fabrics. The correlations are shown to be highly significant, and good estimates of these two subjective properties could be made from the laboratory tests. [ABSTRACT FROM AUTHOR]

The three-dimensional nature of the knitted structure is considered by studying the thickness and compression behaviour of a wide range of plain-knitted fabrics. Compression-recovery curves were obtained for several plain-knitted fabrics in both their dry-relaxed and their completely relaxed states. The compression of the various fabrics is interpreted in terms of several different mechanisms. The effect of fabric tightness on the compression-recovery curves was investigated. The parameters t/l and p were determined for all the fabrics tested, where l is the fabric loop length, t the 'geometrical' thickness of the fabric, and ρ the fabric bulk density. A proportional relation between the parameter t/l and the fabric tightness was found to exist, and this is interpreted in terms of the basic plain knitted-fabric geometry. In addition, a linear relation between fabric bulk density, ρ, and the parameter g K/1·3 was observed, where K is the fabric-tightness factor and g the fibre specific gravity (g = 1·3 g/cm³ for wool). Specific examples cf this general relation agree with experimental observations made by other workers. The variation with fabric tightness of the felting-shrinkage rate for plain-knitted wool fabrics can be explained in terms of the relation between fabric bulk density and tightness factor. [ABSTRACT FROM AUTHOR]

The dimensional properties of cotton and Vincel fabrics in all-over-eyelet constructions are examined in the dry, wet, and washed states of relaxation, in a similar manner to fabrics of close-eyelet construction discussed in Part II of this series of papers. An analytical approach is offered to explain the geometrical properties of the structure in relation to the dimensional characteristics of the constituent stitches. [ABSTRACT FROM AUTHOR]

A reappraisal of previous work on the hairiness of ring-spun yarns that the conclusions reached regarding the effect of fibre characteristics on cotton-yarn hairiness need to be revised. The observed effects can be explained by a simple hypothesis that the mean weight and mean length are the only fibre characteristics that intrinsically affect yarn hairiness. Published data are shown to be inadequate for arriving at satisfactory explanations of the way in which the spinning parameters affect yarn hairiness. The need for the measurement of the hairiness of yarns from the spinning zone and from the instantaneous surface of the cop, in addition to that from the interior of the cop, is established. Methods for these measurements are proposed. The information obtained is shown to be useful in explaining the phenomenon of yarn hairiness and particularly in accounting for the observed differences between different yams. [ABSTRACT FROM AUTHOR]