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Studies the effects of exposure to light of the laser diode Melles Griot (λ = 670nm), He‐Ne laser (λ = 632.8nm) and argon laser (λ = 514nm) on selected soil micro‐organisms, fungi that destroy old manuscripts, pictures, stone, etc. and on humification and mineralization of soil samples. Also studies exposure effects on seed growth and biomass production of a few species of cultivated plants and on Chlorella cells and animal spermatozoa. Finds significant changes in comparison to control material (including results of the preliminary measurement of bio‐photon emission). Suggests a fruitful direction for studies on the synergistic effects of Se, laser and white light, as well as on the optimal level of exposure of living material to laser light. Concludes that the data obtained seem to be useful both for land reclamation and for the protection of the indoor environment against toxicogenic moulds and bacteria.

The main occupational safety measure in factories is monitoring workers exposed to various types of contaminations. The main environmental concern of governments about copper industries is emission of dust, metals, metal compounds and volatile organic compounds in air. The purpose of this paper is to evaluate the immune system status of workers in a copper concentration factory in Iran by placing the emphasis on oxidative stress biomarkers.

A comparative cross-sectional study was performed on 40 workers of the copper concentration factory and 40 unexposed individuals. White blood cell count, plasma interleukin 2 and 4, oxidative burst of neutrophils, oxidative damages of DNA and RNA, lipid and protein, total antioxidant capacity of plasma, and antioxidant enzymes activities were measured.

A significant decrease in the white blood cell count and interleukin 2 and an increase in the interleukin 4 were observed in the workers and these changes represented the possibility of inflammation and weakening of the immune system. The elevation of oxidative damages, total antioxidant capacity and the activity of antioxidant enzymes are indicative of the change in oxidative stress status.

The oxidative stress induction and immune system changes might be useful biomarkers in screening and surveillance for occupational hazard. More studies are needed to find out the type and the concentration of pollutants and to evaluate the protective effects of natural antioxidants.

The purpose of this paper is to demonstrate the similarities and differences of occupational identity among logistics managers, controllers and specialists.

After a thorough review of the literature, the authors opted for desk research and content analysis of job advertisements for these three occupations as the major research method, focusing on a sample of 60 Polish and German advertisements.

The analysis of these data confirmed that the three occupations have their own identity (although there is a certain closeness between controllers and managers), but, from a holistic perspective of logistics management considering current trends in logistics, these three occupations should be integrated as a whole.

This has been the first paper comparing ads focused on logistics professionals in two relevant European economies in terms of logistics development: Poland and Germany.

The separation of energy conversion and propulsor is a promising aspect of hybrid-electric propulsion systems, allowing for increased installation efficiencies and setting the basis for distributed propulsion concepts. University of Stuttgart’s Institute of Aircraft Design has a long experience with electrically powered aircraft, starting with Icaré 2, a solar-powered glider flying, since 1996. Icaré 2 recently has been converted to a three-engine motor glider with two battery-powered wing-tip propellers, in addition to the solar-powered main electric motor. This adds propulsion redundancy and will allow analyzing yaw control concepts with differential thrust and the propeller-vortex interaction at the wing-tip. To ensure airworthiness for this design modification, new ground vibration tests (GVTs) and flutter calculations are required. The purpose of this paper is to lay out the atypical approach to test execution due to peculiarities of the Icaré 2 design such as an asymmetrical aileron control system, the long wing span with low frequencies of the first mode and elevated wing tips bending under gravity and thus affecting the accuracy of the wing torsion frequency measurements.

A flutter analysis based on GVT results is performed for the aircraft in basic configuration and with wing tip propulsors in pusher or tractor configuration. Apart from the measured resonant modes, the aircraft rigid body modes and the control surface mechanism modes are taken into consideration. The flutter calculations are made by a high-speed, low-cost software named JG2 based on the strip theory in aerodynamics and the V-g method of flutter problem solution.

With the chosen atypical approach to GVT the impact of the suspension on the test results was shown to be minimal. Flutter analysis has proven that the critical flutter speed of Icaré 2 is sufficiently high in all configurations.

The atypical approach to GVT and subsequent flutter analysis have shown that the effects of wing-tip propulsors on aeroelasticity of the high aspect ratio configuration do not negatively affect flutter characteristics. This analysis can serve as a basis for an application for a permit to fly.

The presented methodology is valuable for the flutter assessment of aircraft configurations with atypical aeroelastic characteristics.

Discusses a parallel algorithm for the finite‐difference time domain method. In particular, investigates electromagnetic field propagation in two and three dimensions. The computational intensity of such problems necessitates the use of multiple processors to realise solutions to interesting problems in a reasonable time. Presents the parallel algorithm with examples, and uses aspects of graph theory to examine the communication overhead of the algorithm in practice. This is achieved by observing the dynamically changing adjacency matrix of the communications graph.

The purpose of this chapter is to evaluate the role of business schools in corporate social responsibility (CSR) and responsible management education from the business school students’ perspective, and to develop a framework for effective CSR education that meets the Polish students’ expectations.

The chapter starts with a review of CSR concept evolution and importance, with a strong focus on Poland. Next, the review of the responsible management education state in Europe and Poland is presented. Then, an evaluation of CSR and responsible management education in Polish business schools from the students’ perspective is conducted. The evaluation is based on a survey amongst business students of a non-public Polish business school. The practical dimension of the chapter takes the form of a framework of effective CSR education in Polish business schools, presented at the end.

To sum up, the demand for CSR competencies and responsible management is on the rise, both amongst students and employers. The existing international initiatives and accreditation standards give a general idea about the shape of responsible management education, but the exact model must be developed on the regional/country level, as it must include various factors such as the economy, history, culture, academia-business relations or even the dominating teaching model.

The chapter provides a conceptual framework for CSR and responsible management education for those business schools operating in the Polish business context.

The purpose of this paper is to identify and profile clusters of retailers operating in emerging markets, in terms of positioning strategies of their own brands (based on the example of the Polish market).

The study is based on a random sample of 143 medium and large retailers operating in Poland. The data were collected using a CATI method at the end of 2014 and then analyzed with the use of hierarchical and non-hierarchical methods.

With the use of cluster analysis, six clusters of retailers were identified. Members of each cluster refer to different predominant factors when positioning their own brands. Members of each cluster do not differ significantly in terms of descriptive variables (exogenous to the cluster analysis) being used for profiling clusters.

In this study, only retailers operating in Poland were surveyed. This study does not refer to the targeting strategies, which may be analyzed jointly with the positioning strategies of retailers’ brands.

The paper has implications in understanding the approaches to the retailer brand positioning representing by the identified clusters of retailers that might be a basis for the creation of the retailers’ competitive advantages.

The main contribution of this research lies in the clustering approach to segmenting retailers in terms of their own brands’ positioning strategies and identifying clusters of retailers in the Polish market due to the retailer brands’ positioning.

The purpose of this paper is to address a shortfall in the literature dealing with optimal sharing arrangements. In construction projects, where the owner is concerned about multiple project outcomes (cost, time, quality, […]), there exist no guidelines in the literature on what a sharing arrangement should be between the owner and the contractor. This paper gives that arrangement, under defined risk assumptions on the contractor (risk averse ranging to risk neutral) and the owner (risk neutral). The sharing aligns the contractor's interests with those of the owner.

The results are based on solving a constrained maximisation problem involving the expected utilities of both the owner and contractor. Construction practitioners were interviewed in a designed experiment to validate the results.

It is demonstrated that, at the optimum, the proportions of outcomes sharing to the contractor should be higher for outcomes with lower effort cost and a lower level of uncertainty, and by increasing the correlation between outcomes, the fixed component of the contractor’s fee should increase and the proportions to the contractor should decrease.

The theoretical results assume that the contractor is risk-averse ranging to risk-neutral, and that the owner is risk-neutral. The theory is supported through conducting an empirical study based on interviewing a sample of practitioners working for medium-sized contractors, and hence the support is limited to similar situations, until further data are assembled.

By providing a broader understanding of sharing arrangements within contracts, a contribution is made to the current practice of contracts management. The results may be used in the design of contracts, or as benchmarks, by which contracts designed differently, may be compared.

The results address a shortfall in the literature and are an original solution to establishing an optimal multiple-outcome sharing arrangement.

The purpose of this paper is to find an influence of the reduced stiffness of actuators, located on the most outer parts of ailerons, flaperons, rudders, elevators and elevons on the excitation of flutter. This phenomenon is especially important for unmanned aerial vehicles because they continuously use all these control surfaces for trimming and stabilisation and on the other hand, the numerous statistics show that failure of elements of flight control systems are still the most probable reasons of aircraft critical failure.

Flutter calculations were performed by use of the classical modal approach. The normal vibrations of the free aircraft were measured in the ground vibration test (GVT). Test results were used either for verification of the FEM model of the structure – in this case for flutter calculation the MSC.Nastran software was used, or directly for flutter calculation. Based on the flutter analysis, the control surfaces critical for flutter were determined.

These so‐called critical control surfaces –, i.e. surfaces responsible for flutter excitation at first – are localized on outer parts of wing and empennage. It was found that the critical surfaces should have been mass balanced or should be irreversible. In the second case, i.e. when the control surfaces are irreversible, the actuators and drivers should have been of a high reliability, because disconnection of these elements could involve flutter.

This approach within the computational analysis is limited to linear case, otherwise NASTRAN software cannot be used for flutter analysis. GVTs could be performed successfully independently if the structure has linear or non‐linear properties.

It was found that before any flight the stiffness in the flight control system of all control surfaces must carefully be checked and kept above the critical stiffness value. Safety level strongly depends on the reliability of actuators used on such unmanned aerial vehicles. The simulation of disconnection (as a result of damage) of selected control surfaces is possible even if the GVT were provided on undamaged vehicle. To do it, the rotational mode of so‐called “free control surface” should be prepared (as an artificial resonant mode) for all deflected control surfaces; next all the resonant modes should be orthogonalized, relative to this artificial control surfaces mode.

This paper was based on two big European and national projects, and all presented results are original and were never published before. Some selected graphs were shown during the EASN Workshop, Paris, September 2010 at the presentation entitled: “Aeroelastic analysis of remotely controlled research vehicles with numerous control surfaces”.

The risks and uncertainties of public–private partnership (PPP) projects threaten their sustainability. Contract flexibility, which is based on the theory of incomplete contract and transaction cost, may be a viable solution to this issue. The purpose of this study is to investigate the relationship between contract flexibility and the sustainability performance of PPP projects. The multiple mediating roles of justice perception and cooperation efficiency are assessed, thereby allowing the pathways and conditions to be understood more comprehensively for improving the sustainability performance of PPP projects.

Nine hypotheses in the proposed research model are tested via structural equation modeling using data acquired from 218 Chinese PPP professionals.

Results show that contract flexibility positively affects PPP project sustainability performance. Justice perception and cooperation efficiency play direct and sequential mediating roles in this effect.

This study validates that contract flexibility positively impacts the sustainability performance of PPP projects, where justice perception and cooperation efficiency serve direct and sequential mediating roles. The findings of this study contribute to an improved understanding of the effect of contract flexibility on the sustainability performance of PPP projects. Furthermore, they provide important theoretical and practical insights into contract management as well as beneficial information and valuable initiatives for improving the sustainability of PPP projects.