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The paper relates to the problem of adaptation of V-block methods to waviness measurements of cylindrical surfaces. It presents the fundamentals of V-block methods and the principle of their application. The V-block methods can be successfully used to measure the roundness and waviness deviations of large cylinders used in paper industry, shipping industry, or in metallurgy. The concept of adaptation of the V-block method to waviness measurements of cylindrical surfaces was verified using computer simulations and experimental work. The computer simulation was carried out in order to check whether the proposed mathematical model and V-block method parameters are correct. Based on the simulation results, a model of measuring device ROL-2 for V-block waviness measurements was developed. Next, experimental research was carried out consisting in evaluation of waviness deviation, initially using a standard non-reference measuring device, and then using the tested device based on the V-block method. Finally, accuracy of the V-block experimental method was calculated.

The form, waviness and roughness components of a measured profile are separated by means of digital filters. The aim of analysis was to develop an algorithm for one-dimensional filtering of profiles using approximation by means of B-splines. The theory of B-spline functions introduced by Schoenberg and extended by Unser et al. was used. Unlike the spline filter proposed by Krystek, which is described in ISO standards, the algorithm does not take into account the bending energy of a filtered profile in the functional whose minimization is the principle of the filter. Appropriate smoothness of a filtered profile is achieved by selecting an appropriate distance between nodes of the spline function. In this paper, we determine the Fourier transforms of the filter impulse response at different impulse positions, with respect to the nodes. We show that the filter cutoff length is equal to half of the node-to-node distance. The inclination of the filter frequency characteristic in the transition band can be adjusted by selecting an appropriate degree of the B-spline function. The paper includes examples of separation of 2D roughness, as well as separation of form and waviness of roundness profiles.

Quantitative Comparison of Cylindricity Profiles Measured with Different Methods Using Legendre-Fourier CoefficientsThe paper discusses a method of quantitative comparison of cylindricity profiles measured with different strategies. The method is based on applying so-called Legendre-Fourier coefficients. The comparison is carried out by computing the correlation coefficient between the profiles. It is conducted by applying a normalized cross-correlation function and it requires approximation of cylindrical surfaces using the Legendre-Fourier method. As the example two sets of measurement data are employed: the first from the CMM and the second one from the traditional radial measuring instrument. The measuring data are compared by analyzing the values of selected cylindricity parameters and calculating the coefficient of correlation between profiles.

The paper addresses the problem of adaptive strategy of measurements of rotary parts. The authors propose a novel strategy that consists of two stages: a preliminary measurement and additional measurements. During the preliminary measurement, an investigated area is scanned in three equally distant longitudinal sections. Then, the correlation coefficient between the profiles in neighbouring sections is calculated. If the value of the coefficient is lower than the assumed critical value, then additional measurements between the -sections are performed until the value of the correlation coefficient exceeds the assumed critical value. Authors have developed a set of procedures in Wolfram Mathematica to investigate their concept. The paper presents the fundamentals of the method and selected results of its practical verification. Experimental results show capability of the new method to measurement of form deviations of cylindrical parts.

This report describes the first results from coupling of pressurized planar electrochromatography (PPEC) and desorption electrospray ionization (DESI) mass spectrometry (MS). Nine analytes were separated in 2.0 min by PPEC and detected by direct analysis of the TLC plate using DESI coupled to a tandem mass spectrometer. The total analysis time was less than 10 min and sample preparation was minimal. Combination of DESI–MS with PPEC enhances the specificity and sensitivity of detection of analytes in a mixture.

Trypsin autolysis fragments and matrix clusters are often observed as intense peaks in mass spectra of protein digests. It is demonstrated that these can be exploited to improve the mass calibration of a matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) spectrometer. Interpretation of some of the autolysis masses is complicated by the existence of disulfide bonds. Surprisingly large matrix clusters are often visible for α‐cyano‐4‐hydroxy‐cinnamic acid. The fractional part of their masses differentiates them from protein digestion fragments. Copyright © 2002 John Wiley & Sons, Ltd.

The main disadvantage of the standard recursive weighted least-squares algorithm is the unbounded increase in its gain matrix when the covariance vector is not sufficiently rich. We propose a general method for updating the gain matrix. This allows us to derive many new specific algorithms in which the boundedness of the gain matrix is ensured automatically.

In this paper three new adaptive control strategies for linear discrete-time single-input/single-output plants are proposed. They enable globally stable and exponentially convergent adaptive controllers to be designed based on various approaches, such as pole placement and optimal LQ. The principle idea of the strategies proposed is to apply a fixed-parameter control law while the estimates of the plant parameters leave some appropriately chosen region. The persistency of excitation of some external signals is crucial for the stability analysis of an overall adaptive system.