In this paper, the applications of the multivariate data analysis and optimization on vibration signals from compressors have been tested on the assembly line to identify nonconforming products. The multivariate analysis has wide applicability in the optimization of weather forecasting, agricultural experiments, or, as in this case study, in quality control. The techniques of discriminant analysis and linear program were used to solve the problem. The acceleration and velocity signals used in this work were measured in twenty-five rotating compressors, of which eleven were classified as good baseline compressors and fourteen with manufacturing defects by the specialists in the final acoustic test of the production line. The results obtained with the discriminant analysis separated the conforming and nonconforming groups with a significance level of 0.01, which validated the proposed methodology.
Even though the discrimination against women in science have been studied for at least half of the century and any many actions have been taken to promote careers of female researchers, their chances are still far from equal. Many barriers have disappeared, but increasingly precarious model of academic career makes it more difficult for women. The interviews conducted with laureates of prestigious competitions by the Foundation for Polish Science allowed for analysis of what Polish researchers think about the role of gender and parenthood in academic career. The have also served to identify factors that were crucial – according to the interviewed female scientists – for their success in science. As the interviews indicate, the requirements od academic career are the same in case of both: men and women, which could suggest lack of discrimination. On the other hand, the expectation that women will be able to meet the criteria set up by male experiences does not mean equal playing field. To assess real chances for academic success, other non-academic aspects of researchers’ life need to be taken into consideration, especially their limitations for dedicating time to research and for mobility. Young researchers – men as well as women – experience increasing uncertainty in regard to their academic future. Growing competition for employment and research funding, makes it much more difficult for women to fulfil the expectations of a fast-track, mobile career. The interviews formed the basis for identification of support mechanisms in this respect.
The paper provides statistical analysis of the photographs of four various granular materials (peas, pellets, triticale, wood chips). For analysis, the (parametric) ANOVA and the (nonparametric) Kruskal-Wallis tests were applied. Additionally, the (parametric) two-sample t-test and (non-parametric) Wilcoxon Rank-Sum Test for pairwise comparisons were performed. In each case, the Bonferroni correction was used. The analysis shows a statistical evidence of the presence of differences between the respective average discrete pixel intensity distributions (PID), induced by the histograms in each group of photos, which cannot be explained only by the existing differences among single granules of different materials. The proposed approach may contribute to the development of a fast inspection method for comparison and discrimination of granular materials differing from the reference material, in the production process.
When the distribution of water quality samples is roughly balanced, the Bayesian criterion model of water-inrush source generally can obtain relatively accurate results of water-inrush source identification. However, it is often difficult to achieve desired classification results when training samples are imbalanced. Sample imbalance is common in the source identification of mine water-inrush. Therefore, we propose a three-dimensional (3D) spatial resampling method based on rare water quality samples, which achieves the balance of water quality samples. Based on the virtual water sample points distributed by the 3D grid, the method uses the 3D Inverse Distance Weighting (IDW) method to interpolate the groundwater ion concentration of the virtual water samples to achieve oversampling of rare water samples. Case study in Gubei Coal Mine shows that the method improves overall discriminant accuracy of the Bayesian criterion model by 5.26%, from 85.26% to 90.69%. In particular, the discriminative precision of the rare class is improved from 0% to 83.33%, which indicates that the method can improve the discriminant accuracy of the rare class to large extent. In addition, this method increases the Kappa coefficient of the model by 19.92%, from 52.26% to 72.19%, increasing the degree of consistency from “general” to “significant”. Our research is of significance to enriching and improving the theory of prevention and treatment of mine water damage.
As many as three international disputes containing allegations of infringement of the International Convention on the Elimination of All Forms Racial Discrimination (ICERD) have been brought before the International Court of Justice (ICJ), thus contributing to the number of cases allowing the Court to pronounce itself on the international human rights law. Even though none of the cases invoking violations of ICERD has been (yet) adjudicated on the merits, they have already provided an opportunity to clarify (at least in part) the compromissory clause enshrined in Art. 22 of ICERD, as well as to tackle some other issues related to provisional measures ordered by the Court. This article discusses the ICJ’s approaches to the application of ICERD in the three above-mentioned cases, while posing the question whether indeed the 1965 Convention can be useful as a tool for settling inter-state disputes. The author claims that ICERD and the broad definition of “racial discrimination” set out in its Art. 1 constitute cornerstones for the international protection of human rights, though the recourse to the procedures provided in Art. 22 of ICERD – vital as they are – should not necessarily be perceived as a better alternative to the inter-state procedures and the functions exercised by the UN Committee on the Elimination of Racial Discrimination (CERD).
The paper is a review of analog and digital electronics dedicated to monitor nanosecond pulses. Choosing the optimal peak detector construction depends on many factors for example precision, complexity, or costs. The work shows some virtues and limitations of selected peak detection methods, for example standard peak detector with rectifier, sample and hold circuit with triggering units and ADC fast acquisition. However, the main attention is paid to problems of results from effective triggering signal for sample and hold operation. The obtained results allow for designing a peak detector construction as an alternative for costly and very complex fast acquisition systems based on ADC and FPGA technologies.
An application specific integrated design using Quadrature Linear Discriminant Analysis is proposed for automatic detection of normal and epilepsy seizure signals from EEG recordings in epilepsy patients. Five statistical parameters are extracted to form the feature vector for training of the classifier. The statistical parameters are Standardised Moment, Co-efficient of Variance, Range, Root Mean Square Value and Energy. The Intellectual Property Core performs the process of filtering, segmentation, extraction of statistical features and classification of epilepsy seizure and normal signals. The design is implemented in Zynq 7000 Zc706 SoC with average accuracy of 99%, Specificity of 100%, F1 score of 0.99, Sensitivity of 98% and Precision of 100 % with error rate of 0.0013/hr., which is approximately zero false detection.
The paper presents a new construction of an optical pulse amplitude monitoring unit (PAMU) used in a transceiver of Free Space Optics. It consists of a buffer, constant fraction discriminator (CFD), delay line, and a sample and hold (S&H) circuit. In the design FSO system, the PAMU provides to monitor transmitted and received optical pulses with duration of few ns. Using this device, there is no need to apply complicated and expensive digitizing systems. The unique aspect of its construction is to control S&H circuit using the CFD. The lab model of this unit allows to perform tests to define some virtues of constant fraction and leading-edge discriminators. The results were implemented in optical signal monitoring of FSO system. The unit was prepared to cooperate with two different detection modules. Using this setup, it was possible, e.g. to determine operation characteristics of FSO transmitter, identify interruption of transmission, and control light power to provide high safety of work.
In Western music culture instruments have been developed according to unique instrument acoustical features based on types of excitation, resonance, and radiation. These include the woodwind, brass, bowed and plucked string, and percussion families of instruments. On the other hand, instrument performance depends on musical training, and music listening depends on perception of instrument output. Since musical signals are easier to understand in the frequency domain than the time domain, much effort has been made to perform spectral analysis and extract salient parameters, such as spectral centroids, in order to create simplified synthesis models for musical instrument sound synthesis. Moreover, perceptual tests have been made to determine the relative importance of various parameters, such as spectral centroid variation, spectral incoherence, and spectral irregularity. It turns out that the importance of particular parameters depends on both their strengths within musical sounds as well as the robustness of their effect on perception. Methods that the author and his colleagues have used to explore timbre perception are: 1) discrimination of parameter reduction or elimination; 2) dissimilarity judgments together with multidimensional scaling; 3) informal listening to sound morphing examples. This paper discusses ramifications of this work for sound synthesis and timbre transposition.
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