Conventional steel-braced outrigger trusses are widely used to control lateral deformation in super high-rise buildings, but their high axial stiffness can create abrupt stiffness discontinuities at the strengthened story and amplify deformation and internal-force demands in adjacent stories. Braces with intentional eccentricity (BIEs) offer an alternative by partially decoupling stiffness from strength, enabling a flexible strength-stiffness design strategy without reducing ultimate brace strength. This study investigates a 71-story super high-rise building equipped with BIE outrigger trusses and compares it with an otherwise identical building using conventional steel-braced (CSB) outrigger trusses. The building is designed according to Chinese code requirements and assessed through response-spectrum analysis under frequent earthquakes and nonlinear time-history analysis under rare earthquakes. A preliminary method is also developed to estimate the optimal strengthened-story location by accounting for eccentricity-induced stiffness reduction. Results show that BIE outrigger trusses reduce abrupt deformation changes at the outrigger level, lessen internal-force amplification in adjacent beams and columns and promote uniform seismic deformation along the building height. Compared with CSB outriggers, the BIE system reduced the sudden change in inter-story drift near the strengthened story by approximately 58% and reduced wall-beam yielding by approximately 17% on average. Optimizing the strengthened-story location further reduced the maximum average story drift and increased the relative drift-control advantage of BIE over CSB. These findings indicate that BIE outrigger trusses can improve seismic resilience through controlled flexibility, enhanced energy dissipation and greater freedom in strengthened-story placement.
Industrial process heat production is responsible for a great amount of CO2 emissions due to fossil fuel consumption. The electrification of this domain, mainly with the use of high temperature heat pumps (HTHPs), is a promising way for designing sustainable industrial units. In this context, the present study investigates in detail reverse Brayton HTHPs with Air and supercritical carbon dioxide (sCO2) as working fluids. Initially, conventional reverse Brayton HTHPs, with and without an internal heat exchanger (IHX), are analyzed using Air and supercritical CO2 (sCO2). Subsequently, a cascade reverse Brayton HTHP is proposed and evaluated for the first time. Notably, two cascade designs are studied: the first one with Air in one stage and sCO2 in the other (sCO2/Air), while the second one implements sCO2 in both stages (sCO2/sCO2). The cascade concept aims to mitigate the extremely high operating pressures of conventional sCO2cycles while maintaining high thermodynamic performance. The analysis is conducted using mathematical models developed in the MATLAB programming environment, while the thermophysical properties of the working fluids are obtained using CoolProp. According to the thermodynamic simulation results, the systems with sCO2 have significantly higher performance compared to the systems with Air. The coefficient of performance and the exergy efficiency are computed to be up to 73.17% and 57.44% higher than those of the Air-based units, respectively. The cascade designs achieve higher efficiency compared to the Air designs, but lower than the conventional sCO2 designs due to the exergy destruction in the cascade heat exchanger. However, it is found that the cascade sCO2/sCO2 system leads to reasonably high pressure levels and to sustainable designs, especially in medium and high process heat temperature levels, as the high-pressure levels are reduced by about 20-50%. It is concluded that the Cascade sCO2/ sCO2 system has potential for process heat production in ultra-high temperatures, but with the proper design and by exploiting suitable waste heat streams. Finally, all reverse Brayton HTHP configurations reduce annual CO2 emissions compared with a natural gas boiler, whereas conventional sCO2-based configurations are the most costeffective solutions.
This study evaluates fixed-tilt reflector-assisted floating photovoltaic (FPV) and land-based photovoltaic (LPV) systems at Kremasta Lake, Greece, through a coupled analysis of irradiance, shading, thermal response, PV-module and reflector degradation, technical lifetime, maintenance, and economics. For a reflector tilt of 10∘, the maximum first-year energy yield occurs at a PV tilt of 43∘ and an initial reflector reflectivity of ρ0=0.95, providing annual energy gains of 18.41% for FPV and 17.86% for LPV relative to their respective optimal reflector-free configurations. Reflector-enhanced irradiance increases module temperature, with a maximum hourly temperature-induced efficiency penalty of 3.84% for the 10∘ reflector configuration. The maximum annual PV degradation rate increases from 0.89% to 1.26% yr–1 for FPV and from 1.17% to 2.45% yr–1 for LPV under the most severe reflector-assisted conditions. Consequently, at the first-year energy-optimal configurations, the modelled PV technical lifetime decreases from 26.03 to 18.57 years for FPV and from 19.97 to 9.98 years for LPV. When material-dependent reflector ageing, cleaning, replacement, and technology-specific O&M costs are included over a 20-year project horizon, the economic optimum shifts to ρ0=0.75. The minimum FPV LCOE decreases from 46.59 to 45.90 EUR/MWh, whereas the corresponding LPV LCOE increases from 46.50 to 47.49 EUR/MWh. These results demonstrate that the reflector configuration maximizing first-year energy is not the configuration minimizing lifetime electricity cost, and that reflector integration is economically more compatible with FPV than with LPV under the investigated conditions.
Maritime Autonomous Surface Ships (MASS) require safety assessments that connect systemic control deficiencies with quantitative evaluation of component and functional failures. However, existing approaches provide limited operational guidance for maintaining traceability between system-theoretic causal analysis, quantitative modelling, and risk-informed design decisions. This study refines and operationalizes a parallel and architecturally synchronized STPA–FTA framework and applies it quantitatively to a Degree of Autonomy 4 Collision Avoidance System (CAS). STPA and FTA were developed within a shared architecture, preserving traceability from unsafe control behavior and causal mechanisms to fault-tree events and design changes across four operating modes. The integrated analysis identified situation-awareness and communication contributors as dominant and revealed additional safety-critical control and interaction deficiencies not captured by component rankings alone. These findings directly informed a structural reconfiguration of the CAS. Across the four operating modes, the reconfigured architecture reduced the modeled probability of CAS functional failure by 83–88% and eliminated multiple single-point failure pathways. Sensitivity analysis indicated that the principal operating-mode and contributor rankings remained broadly consistent. The results demonstrate how the refined framework can support traceable identification of safety vulnerabilities and the evaluation of risk-informed architectural improvements during the design of safety-critical MASS functions.
This research aims to record hotel owners' perceptions as subjective measures of the degree of integration of local traditional cheese varieties in the hospitality sector. Within the context of cheese tourism, this specific type of alternative tourism is operationalized through B2B co-creation among tourism businesses and cheese factories, serving as a framework for perceived business development. Specifically, this study fills a gap in the literature by exploring the managerial views on the current state of cheese tourism in relation to the entrepreneurship strengthening, the opportunities, and challenges that could favor cooperation between the two sectors. Descriptive and inductive statistics were conducted, collecting primary data from hotels in the Peloponnese, Greece, which has a long tradition of cheese production. Regional tradition and star rating determine the integration of local cheese. While 4-5-star hotels leverage cheese heritage for differentiation and experiential services, lower-end hotels face cost and supply chain barriers, requiring supporting strategies and cross-sector partnerships. The study offers original knowledge for the development of specific strategic proposals for the use of cheese tourism through co-creation for business development of hotels. Future research is recommended to record the views of all stakeholders and correlate them with objective financial performance.
