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Officially, of course, the world is now post-imperial. The Q’ing and Ottoman empires fell on the eve of World War I, and the last Leviathans of Europe's imperial past, the Austro-Hungarian and Tsarist empires, lumbered into the grave soon after. Tocsins of liberation were sounded on all sides, in the name of democracy (Wilson) and socialism (Lenin). Later attempts to remake and proclaim empires – above all, Hitler's annunciation of a “Third Reich” – now seem surreal, aberrant, and dystopian. The Soviet Union, the heir to the Tsarist empire, found it prudent to call itself a “federation of socialist republics.” Mao's China followed suit. Now, only a truly perverse, contrarian regime would fail to deploy the rhetoric of democracy.

The wording “atypical forms of employment” is grounded on juxtaposing it with typical employment, i.e. full‐time employment, for indefinite period and in one place of work. However one can notice that different forms of atypical work have spread so much at present that the expression “atypical” is becoming less and less adequate for the majority of them.

The aim of this paper is to find the electrical representation of a solid oxide fuel cell (SOFC) that enables the application of typical exploitation characteristics of fuel cells for estimation of fuel cell parameters (for example, exchange current) and easy analysis of phenomena occurred during the fuel cell operation.

Three-layer structure of an SOFC, where a thin semi-conducting layer of electrolyte separates the anode from the cathode, shows a strong similarity to typical semiconductor devices built on the basis of P-N junctions, like diodes or transistors. Current–voltage (I-V) characteristics of a fuel cell can be described by the same mathematical functions as I-V plots of semiconductor devices. On the basis of this similarity and analysis of impedance spectra of a real fuel cell, two electrical representations of the SOFC have been created.

The simplified electrical representation of SOFC consists of a voltage source connected in series with a diode, which symbolizes a voltage drop on a cell cathode, and two resistors. This model is based on the similarity of Butler-Volmer to Shockley equation. The advanced representation comprises a voltage source connected in series with a bipolar transistor in close to saturation mode and two resistors. The base-emitter junction of the transistor represents voltage drop on the cell cathode, and the base-collector junction represents voltage drop on the cell anode. This model is based on the similarity of Butler-Volmer equation to Ebers-Moll equation.

The proposed approach based on the Shockley and Ebers-Moll formulas enables the more accurate estimation of the ion exchange current and other fuel cell parameters than the approach based on the Butler-Volmer and Tafel formulas. The usability of semiconductor models for analysis of SOFC operation was proved. The models were successively applied in a new design of a planar ceramic fuel cell, which features by reduced thermal capacity, short start-up time and limited number of metal components and which has become the basis for the SOFC stack design.

The argument presented in this paper is based on distinctive and exploitable differences which merit putting eco-tourists, eco-resorts and the coastal tropics into categories of their own. Such differences should inform planning and design process when working in this environment, which is both very sensitive and valuable. The paper aims to describe the main characteristics of the coastal tropics as a climate targeted by eco-tourism. Differences between eco-tourists and residents are presented through definition of comfort. Climatic and other factors influencing comfort limits are at the core of discussion, in which passive design is seen as the most appropriate response to challenges of the tropical coast setting. The design opportunities for the desirable climate modifications in eco-friendly resorts together with some passive design features are briefly presented. These architectural design solutions are set against theoretical principles specific to tropical coastal regions. The focus is on human responses to environmental factors, and on their implications. The paper concludes with a few recommendations aimed to deliver indoor conditions consistent with climatic preferences of itinerant environmentally conscious users of buildings in the coastal tropics. Such an approach is expected to minimize impacts the facility will make on the environment.

The purpose of this qualitative study is to explore the role of spirituality, understood as a personal relationship with God, in missionary intercultural experience.

We conducted narrative interviews with eight Polish consecrated missionaries in Argentina, Bolivia, Ecuador, Peru and Paraguay. We used thematic analysis to establish spirituality in missionary experience and narrative analysis to examine sensemaking processes.

Missionary spirituality was defined by a personal relationship with God as a source of consolation, psychological comfort, strength to cope with distressing experiences, and Grace promoting self-improvement. It compensated for the lack of family and psychological support and enhanced psychological adjustment to the environment perceived as dangerous. Spirituality helped missionaries deal with cultural challenges, traumatic and life-threatening events. Traumatic experiences furthered their understanding of the mission and triggered a spiritual transition that entailed a change in their life, attitudes and behavior.

Comparative research into religious vs nonreligious individual spirituality in the experience across various types of expats in various locations could capture the professional and cultural specificity of individual spirituality. Research is also needed to link spirituality with expat failure.

Catholic agencies and institutions that dispatch missionaries to dangerous locations should consider providing professional psychological assistance. Narrative interviewing could be used to enhance missionaries' cultural and professional self-awareness, to better serve the local community. Their stories of intercultural encounters could be incorporated into cross-cultural training and the ethical and spiritual formation of students and future expats.

This study captures a spiritual aspect of intercultural experience of under-researched expats. It offers a model of the involvement of individual spirituality in coping in mission.

In this paper results of numerical analysis of the ground resonance are shown. This analysis is performed making use of the complete model of the one‐main rotor helicopter. This model is adopted from flight mechanics. For the basic analysis it is assumed that the helicopter fuselage is a rigid body and the main rotor consists of four rigid blades. Each blade performs motions about its horizontal flapping hinge and vertical lagging hinge. The tail rotor is treated as a hingeless and weightless source of thrust, which equilibrates the drag moment and ensures directional control of the helicopter. For analysis of the ground resonance phenomenon, forces and moments produced by the landing gear are taken into account – their rigidity and damping are included into consideration.

The Cyprus conflict is a classical case of protracted ethnic conflict with very obvious and important international dimensions. It is one of the major unresolved inter national conflicts, which for decades attracts the attention of the international community. The involvement of many countries and international organizations in the Cyprus conflict demonstrates the importance and seriousness of the conflict. During the last decades the conflict has cost a lot both for the Greek Cypriots and for the Turkish Cypriots. It claimed a lot of lives and caused serious economic damages and psychological destruction. The conflict began in the 1950s, erupted violently with blood shed at the end of 1963,and culminated in 1974 with the interventions of Greece and Turkey that led to the island’s current de facto division as the Greek Cypriot South and Turkish Cypriot North. Over the past 40 years many states have came out with various initiatives and have proposed various approaches for final settlement of the conflict. It also has been addressed by dozens of UN Security Council resolutions but all these have proved to be futile so far.

The purpose of the present paper is to show a comparative analysis of classical and modern heuristics such as genetic algorithms, simulated annealing, particle swarm optimization and bacterial chemotaxis, when they are applied to electrical engineering problems.

Hybrid algorithms (HAs) obtained by a synergy between the previous listed heuristics, with the eventual addiction of the Tabu Search, have also been compared with the single heuristic performances.

Empirically, a different sensitivity for initial values has been observed by changing type of heuristics. The comparative analysis has then been performed for two kind of problems depending on the dimension of the solution space to be inspected. All the proposed comparative analyses are referred to two corresponding different cases: Preisach hysteresis model identification (high dimension solution space) and load‐flow optimization in power systems (low dimension solution space).

The originality of the paper is to verify the performances of classical, modern and hybrid heuristics for electrical engineering applications by varying the heuristic typology and by varying the typology of the optimization problem. An original procedure to design a HA is also presented.

The purpose of this paper is to develop a novel active disturbance rejection attitude controller for quadrotors and propose a controller parameters identification approach to obtain better control results.

Aiming at the problem that quadrotor is susceptible to disturbance in outdoor flight, the improved active disturbance rejection control (IADRC) is applied to design attitude controller. To overcome the difficulty that adjusting the parameters of IADRC controller manually is complex, paired coevolution pigeon-inspired optimization (PCPIO) algorithm is used to optimize the control parameters.

The IADRC, where nonlinear state error feedback control law is replaced by non-singular fast terminal sliding mode control law and a third-order tracking differentiator is designed for second derivative of the state, has higher control accuracy and better robustness than ADRC. The improved PIO algorithm based on evolutionary mechanism, named PCPIO, is proposed. The optimal parameters of ADRC controller are found by PCPIO with the optimization criterion of integral of time-weighted absolute value of the error. The effectiveness of the proposed method is verified by a series of simulation experiments.

IADRC can improve the accuracy of attitude control of quadrotor and resist external interference more effectively. The proposed PCPIO algorithm can be easily applied to practice and can help the design of the quadrotor control system.

An improved active disturbance rejection controller is designed for quadrotor attitude control, and a hybrid model of PIO and evolution mechanism is proposed for parameters identification of the controller.