## 1 Introduction and Formulation of the Problem
In this paper, we present the results of voltammetric research of a temporal series of current and potential, formed in repeated redox processes of solute components in conditions where one electroactive analyte is slightly varied. As the analyte to be varied, we chose the d-tryptophan amino acid. This choice is supported by the fact that this acid participates in different electrochemical oxidation reactions, varying its activity depending on the material of the used electrode. It is important also that d-tryptophan refers to one enantiomer, and its presence as a mixture in pharmaceuticals is extremely undesirable. Therefore, one can expect its signal on a level comparable with that of random fluctuations/noises. The application of a multisensor electrochemical system becomes inefficient if the number of detected components is large and the sensitivity of each micro-sensor forming the desired system is low. The selection of d-tryptophan as an analyte is stipulated also by thefact that, depending on the material of the electrode (C or Pt), this amino acid exhibits different electric activity in the oxidation reaction. At \"trace\" concentrations of d-tryptophan, both electrodes \"feel\" the concentration variations in the presence of a microcomponent. This behavior of the used multisensor having low sensitivity is characterized as \"delayed\" behavior. In many cases, this behavior is related to the mathematical method used for the extraction of a weak signal [10; 11; 12; 13]. In our case, on C-electrodes, the d-tryptophan is oxidized easily with formation of a clearly expressed signal; however, on Pt-electrodes, it does not give clearly oxidized peaks. Therefore, part of the useful information is lost. In this paper, we propose a general method free from treatment errors, which can improve the sensitivity of existing multisensor systems. In this paper, we try to solve the following problems:  
1. Determination of some output parameters that are related to monotone concentration of the electroactive components in conditions of strongly fluctuating currents on the C(\"active\") and Pt (\"inertial\") electrodes, for construction of the desired calibration curves. 2. Comparison of the obtained characteristics for the C- and Pt-electrodes and derivation of the calibration/monotone curves with respect to the given d-tryptophan concentration. For solution of these problems, we propose a general method that enables comparing two random sets in a two-dimensional (2D) plane. The advantages of the proposed method are as follows:  
1. Its generality (universality) implies the potential to compare _any_ couple of random sets assigned by their coordinates (\(Y1_{k}\), \(Y2_{k}\)) in a 2D plane. 2. All parameters are expressed in terms of the integer moments and their inter-correlations. 3. The number of parameters is finite, and they have clear geometrical interpretation. 4. The proposed method oriented for analysis of discrete sets is free from _any_ unjustified supposition and treatment errors. 5. The proposed approach can compare random sequences having different sampling volumes in the frame of the _same_ set of statistical parameters. Here, it is appropriate to compare the DGI approach with classical statistical mechanics, when a small number of statistical parameters associated with their averaged motion (T, \(V\), \(P\), \(\upmu\)) replaces a large number of parameters (\(3N\)) characterizing the micromotions of atoms and molecules. In our case, two random sequences having \(2N\) data points are reduced to the analysis of eight statistical parameters associated with integer moments and their inter-correlations. In addition to this reduction, one can see also the desired curve in a 2D plane (Equations (A7) and (A18)), reflecting the behavior of these parameters. The proposed approach is free from model assumptions related to the nature of the compared random sequence/noise.