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The risk of hail-impact occurrence that can decrease local strength property must be taken into account in the design of primary airframe structures in aviation, energy and space industries. Because of the high-speed of hail impact in operation, it can affect the load carrying capacity. Testing all impact scenarios onto real structure is expensive and impractical. The purpose of this paper is to present a cost-effective hybrid testing regime including experimental tests and FEM-based simulations for airframe parts that are locally exposed to the impacting hail in flight.

Tested samples (specimens) are flat panels of laminated and sandwich carbon/epoxy composites that are used in designing lightweight new airframes. The presented numerical simulations provide a cost effective and convenient tool for investigating the hail impact scenarios in the design process. The smoothed particle hydrodynamics (SPH) technique was selected for the simulation of projectiles. The most commonly used shape of projectiles in hail impact tests is the ice ball with a defined diameter. The proposed simulation technique was verified and validated in tests on flat composite panels (specimens).

Integration of the numerical analyses with high-speed impact tests of hail onto flat laminated and sandwich composite shells has been presented, and a developed simulation model for impact results assessment was obtained.

The tested coupons (specimens) are flat panels as representative of structural design deployed in real aircraft structures. These numerical simulations provide a cost effective and convenient tool for hail impact scenarios in the design process.

Cities’ population growth goes in hand with the development of new technologies that are becoming the key factor of the Smart City (SC) concept. It allows the implementation of efficient management solutions, operation, and sustainable development of a city to face the challenges of urbanization and improve the services for the citizens and visitors.

The concept of the SC 5.0 was first presented in Svítek, Skobelev, and Kozhevnikov (2020), where the problems of the complexity of current cities due to rigid management processes, variety of infrastructure, and SC modules, systems, subsystems, and applications were described.

To prove the concept, several practical examples were developed to cover the topics: modeling in SCs, practical implementation of multiagent technologies, the approach of creating city ontology and the city knowledge base as the instrument of semantic interoperability, and visualization possibilities of Smart Evropská as a SC Testbed used for teaching purposes.

The new organizational structure is proposed based on knowledge graphs, and practical examples are shown. The applicability of knowledge graphs to be used in combination with data management platforms for monitoring SC key performance indicators (KPIs) and providing interoperability of services is presented.

Existing research indicates that collective identity is critical in sustaining social movements, especially in the face of significant opposition. We extend this literature by analyzing the ways collective identity evolves and develops over time to combat external barriers and obstacles. Drawing from a unique dataset on activists in the post-communist Czech environmental movement, we analyze how women rallied around their gendered identity to protest against nuclear power. Our analysis focuses on the case of the South Bohemian Mothers (Jihočeské matky), an organization that rallied specifically around the protection of children and healthy communities. The activists faced extensive obstacles including: post-communist patriarchal institutions and sexism; the South Bohemian Daddies, a male-dominated pro-nuclear countermovement; and pervasive anti-environmentalist sentiments. Our results highlight the complex and evolutionary nature of collective identity and the role it can play in sustaining activism in the face of external challenges.

The purpose of this paper is to analyse Czech’s activation reforms enacted since 2006 which culminated in 2010-2012 as radical workfare-like reforms. It also aims to explain which factors have influenced their development.

The paper is the case study of activation reforms in one country interpreted within the theoretical framework of the “activation models” and discussion of the factors influencing activation reforms. The design and implementation of the reforms of activation policies are in focus. Institutional analysis is combined with secondary statistical data and survey data.

The author distinguish three phases of the activation reforms: the initial phase of activation (work first), the radical phase (workfare) and the failure of radical workfare as the final phase. The key argument is that the main factors leading to the radical workfare version of activation were the political factors combined with institutional factors, particularly, the specific model of policy making (the so-called “compost model”). Ironically, this model which has enabled fast and radical workfare-like reforms was also the main reason why the reforms failed.

The paper is innovative since it explains the specific features of the activation reforms in the Czech Republic, distinguishing workfare from other models of activation, and identifying the factors which have played a role in shaping these features. The in-depth case study of one country provides the evidence on the role of the specific factors and helps the author to understand the motives, the design and the implementation of activation reforms in their mutual relationships. The specific role of the institutional legacy in the new circumstances is emphasized.