Essays in Physics

“Essays in Physics” gives accounts of 32 chosen topics. The level is that of a 3–4-year university course in Physics. The topics discussed are diverse but “mainstream”. Each essay aims to say something fresh that complements what the reader will find elsewhere. Just what “fresh” means inevitably depends somewhat on the subject matter. Some chapters give a “different” slant on a familiar idea (e.g. electromagnetic energy, Lorentz transformation, photon emission). Some contain an analysis not available elsewhere (diffraction, feedback stability). Some correct material that is commonplace in many textbooks (much atomic physics). Some add insightful discussion to standard material (free energy, Brillouin zones). One in particular refines technique (perturbation theory). One brings order to confusion (-m dB). The aim in all cases is to encourage a fuller, and correct, understanding, and an enhanced intellectual acuity (critical faculty). With a subject as mature as physics, it is bold to claim originality. However I will dare to make that claim, in particular for Chapters 10, 22 and 30, but also for parts of most other chapters.

Trust Marketing in the Stakeholder Network: Mechanism, Sources and Process of Forming Trust Relationships

The presented publication is aimed at determining the mechanism and sources of formation of trust relationships in the stakeholder network and closer defining the content of the process of their formation. The article defines the most significant sources of formation and strengthening of trust relations at the microeconomic level, which are: openness and availability of information; solving social problems; ability of each participant in the relationship to express their interests and influence the decision-making; integrity, honesty and competence of managers; clear feedback; stability of contractual relations and partnerships; high reputation and developed organizational culture of companies. Trust in the stakeholder network has a mechanism of occurrence, which consists of an aggregate of trust states of participants in relationships and processes by which these states are formed in them. Determining the sources of trust and the mechanism of its occurrence in the stakeholder network gives grounds for the development and adjustment, if necessary, of the process of establishing and developing trust relationships between network members. The incentive, cognitive, instrumental, practical and final stages of the process of formation of trust relations in the stakeholder network are also allocated, which makes it possible to structure the process of trust formation in the system of relations between the company and stakeholders and harmonize it with the stakeholder analysis and management process.

An LMI Approach to Nonlinear State-Feedback Stability of Uncertain Time-Delay Systems in the Presence of Lipschitzian Nonlinearities

This article proposes a new nonlinear state-feedback stability controller utilizing linear matrix inequality (LMI) for time-delay nonlinear systems in the presence of Lipschitz nonlinearities and subject to parametric uncertainties. Following the Lyapunov–Krasovskii stabilization scheme, the asymptotic stability criterion resulted in the LMI form and the nonlinear state-feedback control technique was determined. Due to their significant contributions to the system stability, time delays and system uncertainties were taken into account while the suggested scheme was designed so that the system’s stabilization was satisfied in spite of time delays and system uncertainties. The benefit of the proposed method is that not only is the control scheme independent of the system order, but it is also fairly simple. Hence, there is no complexity in using the proposed technique. Finally, to justify the proficiency and performance of the suggested technique, a numerical system and a rotational inverted pendulum were studied. Numerical simulations and experimental achievements prove the efficiency of the suggested control technique.