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This paper aims to improve the mathematical justification of certain analog signal theory concepts and offer a rigorous framework for it.

The framework relies on functional analysis, namely theory of distributions and the concept of weak limit. Its notation is adjusted to resemble the notation usually used in engineering signal theory. It can be used to prove in a rigorous manner already established results in signal theory, but also to establish new ones.

Examples have shown the lack of rigour caused by using ordinary calculus in proving fundamental signal theoretic results. On that basis, concepts of limit, Fourier transform and derivative are revisited in the spirit of functional analysis. A new useful formula for weak limit computation is proved.

Functional analysis is efficiently used in signal theory in a manner approachable by engineers. An original and efficient formula for weak limit computation is presented and proved.

A fast identification algorithm for a linear monotonic process from a step response is proposed in this paper, from which the parameters of a first‐order plus dead‐time model can be obtained directly.

The study is based on a non‐asymptotic distributional estimation technique initiated without delay in the framework of systems. Such a technique leads to simple realization schemes, involving integrators, multipliers and piecewise polynomial or exponential time functions and shows a possible link between simultaneous identification and generalized eigenvalue problems. Thus, it allows for a real‐time implementation.

The effectiveness of the identification method has been demonstrated through a number of simulation examples and a real‐time test.

This paper presents a novel method to simultaneous delay and parameters identification of a stable first‐order plus time delay model from step response that can model a widespread class of systems.

Knowledge management (KM) is an important consideration in e‐government portals to ensure that knowledge flows efficiently between governments, individuals and organisations. A crucial aspect of e‐government portals that has not been addressed adequately is the extent to which KM mechanisms have been implemented. Specifically, the authors argue that appropriate KM mechanisms are necessary to support the access, creation and transfer of knowledge between these portals and their users. The paper aims to propose an evaluation model for this purpose by first defining the main KM mechanisms and then burrowing deeper into their constituent dimensions.

An evaluation model known as knowledge access, creation and transfer (K‐ACT) is presented which identifies three KM mechanisms for portals: knowledge access, creation and transfer. Each mechanism is characterised by a set of dimensions and sub‐dimensions representing the tools and features for supporting that mechanism. The model was derived from an analysis of the literature and validated by two independent reviewers who were trained in information science, were familiar with the objectives of the project and understood the concepts underlying KM implementation in portals. Using this model, a checklist was developed and applied to 60 e‐government portals in the Asian and North American regions to investigate the extent to which these KM mechanisms have been implemented.

The findings indicate that, on average, e‐government portals featured only about 36 per cent of the KM mechanisms described in the model. Furthermore, no significant differences in the implementation of the KM mechanisms were found between the two regions' portals. The evaluation also offered potential areas for improvement based on the K‐ACT model.

The present work has developed an evaluation model known as K‐ACT which can be used to assess KM implementation gaps in e‐government portals. This model can also be generalised to other types of portals. The evaluation also provides insights into the state of KM processes in the portals of the Asian and North American regions.

This paper deals with mathematical and numerical methods for defining optimal therapeutics associated with drugs action models. To obtain the optimal control corresponding to some criteria analytical and numerical methods are proposed. An original optimization technique giving the global optimum will be described and used. It is based on a space filling curve idea. A new variant of the dynamic programming method is also proposed, this leads to a simple optimization problem.

To describe and extend existing concepts of discrete electromagnetism in a unified formalism; to give examples for the usefulness of the presented ideas for our theoretical work, especially with regard to energy.

After a concise introduction to the mathematical concepts of discrete electromagnetism, we introduce continuous de Rham currents and give their discrete counterpart. We define operators acting upon discrete currents, and apply the theory to electromagnetism.

de Rham current theory yields a mathematical framework for the discussion of discrete electromagnetic problems: The focus is on energy‐balance equations; a discrete Lagrangian can be defined for various modeling problems; the Galerkin approach fits nicely into the proposed formalism; boundary terms in discrete formulations are an implicit feature to the theory.

In this paper, we use the interpolation of discrete fields by Whitney forms on a simplicial cell complex. The resulting discrete formulation is identical to a Galerkin finite‐element method. Other numerical techniques that do not resort to Whitney‐form interpolation can equally be discussed in de Rham‐current terminology.

Rather than a novel numerical technique, the paper presents a unified mathematical framework for the discussion of different practical approaches. We advocate a canonical treatment of energy‐related quantities and of boundary terms in discrete formulations.

This study was undertaken to determine what trends have been occurring in price discrimination in the United States over the past 25 years. The vehicle here will he U.S. District Court actions filed and decisions rendered under the Robinson‐Patman Act from 1961 through 1986. Marketing practitioners and educators have long been discussing the relative impact of the Robinson‐Patman Act on pricing practices. In the years following passage of the Act in 1936, these marketing professionals have felt that noncompliance would bring down the wrath of the federal government. And, for the most part, this fear was well founded. If, in fact, Robinson‐Patman is alive and well today, are large firms practicing discriminatory pricing? If so, are they discriminating and not being prosecuted? Or are they discriminating in price, being prosecuted, and not being convicted of the charge?

The aim of this article is to draw attention to the importance of open discussion for the proper development of science.

In the phase of the developed market economy we are currently in, the evaluation of each human activity, including scientific work, which is based on an evaluation of the value of the profit it brings. Unfortunately, it does not always work correctly.

The problem will be analyzed using as an example the erroneous (according to the author) use of fractional derivatives in electrical engineering.

To the best of the author’s knowledge, this is the author's original point of view on the problem of improper use of fractional derivatives in electrical engineering.

On May 17, 2012, the social networking company Facebook Inc. fixes its initial public offering (IPO) price at $38.00 a share. Over the next couple of months, contrary to expectations raised by previous IPOs, the stock price crashes more than 50 per cent. Immediately, the question arises whether the issuer’s or the stock market’s pricing of the share are in line with the firm’s fundamentals. Thus, the purpose of this paper is to determine the company value in close proximity to the date of IPO.

As Facebook is an archetypal internet growth company, it is evaluated using the Schwartz/Moon model. This approach features significant advantages over traditional valuation models and more adequately captures the characteristics of growth companies.

As of September 30, 2012, the fundamental share value determined was $26.53, which exceeded the market price per share of $22.66 by 22.48 per cent, but was far less than the IPO stock price. The subsequent sensitivity analysis reveals the robustness of the result to key input parameters.

The results raise doubts about the IPO price of Facebook. Furthermore, this paper is of value from a more conceptual perspective in that an extended version of the Schwartz/Moon model is provided. Beyond extensions previously discussed in the subject-based literature, the authors include stochastic interest rates (as an additional source of uncertainty) and investigate their valuation effects.

The purpose of this paper is to analyze business model (BM) and intellectual capital (IC) of a firm with a focus on their common elements. The common bases in the field of strategic management for these two concepts are, among others, resource-based view, knowledge-based view, intellectual capital-based view, dynamic capabilities, and configurational approach. It indicates areas in which these two concepts can benefit from each other, e.g. in classification of components, their configuration, or dynamic approach. This general review examines the following research questions: What are the common concepts for the BM and IC? What are their common components? What does the dynamic approach to IC and BM mean?

The Web of Science™ Core Collection database was selected for the period 1975-2014 and the Journal of Intellectual Capital (JIC) indexed in Scopus^® (Elsevier) was incorporated into the analysis for the period it had been indexed by Scopus (1990-2015). These databases were selected because they offer a reliable overview of historical data regarding journals, articles, and citation impact. The key filter criteria were the presence of the phrases “business model” or “intellectual capital” in the article title, abstract, and key words in order to narrow down the selection to the most appropriate results for the research area.

This paper investigates two concepts from the point of view of their underpinnings in management, definitions, and components, as well as value creation. Analysis of the foundations in management allows the author to present a cohesive model, which depicts a comprehensive approach to analysis of these two concepts. Many common elements have been identified and investigated.

First, it provides an indication of the common underpinnings of the analyzed concepts within the framework of strategic management and proposals for their development toward resource, knowledge, and IC accumulation, combination and heterogeneity-based views. Second, it presents an analysis of the BM and IC components, showing common elements between them. Third, it provides a description and analysis of dynamic view of BM and IC components in a value creation context.