Search Results (266)

Renewable energy curtailment has emerged as a growing challenge on the Korean mainland grid as photovoltaic (PV) and wind power capacity continues to expand toward national carbon neutrality targets. Plus demand response (Plus DR), in which electricity consumers increase consumption during curtailment periods, has been introduced as a demand-side mitigation measure. Buildings represent a potential resource for Plus DR participation. However, existing studies have primarily focused on load-reduction DR, and Plus DR availability by building use type under curtailment conditions has not been systematically quantified. This study estimates Plus DR availability of building loads by use type—department store, hotel, general commercial, public facility, apartment, and school—based on representative building load profiles, PV generation data, and 2025 curtailment occurrence data from the Korean mainland grid. Curtailment events were concentrated in the 10:00–16:00 window with peak frequency at 12:00 (80 events). The combined Plus DR availability across the six use types averaged 290.3 kW during curtailment hours, peaking at 300.9 kW at 14:00. The estimated Plus DR availability operated primarily through the load-increase pathway (additional grid consumption) rather than the surplus absorption pathway (reduced PV export). Surplus generation was observed only in the school at 13:00 (0.77 kW). These results provide a quantitative basis for identifying suitable building types and curtailment-responsive time windows for building-based Plus DR program design on the Korean mainland, and may serve as a reference for mainland DR market development. Full article

Growing environmental pressures have increased interest in zero-waste practices within the hospitality industry, while digital platforms have become key spaces where such practices are interpreted and debated. However, limited research has examined how zero-waste hospitality is represented in digital public discourse. This study addresses this gap by analyzing 10,944 posts from X (Twitter) collected globally in English using an integrated approach combining text mining, sentiment analysis, and topic modeling implemented in Python (v3.14.5). The findings indicate that online discussions are predominantly neutral and positive, suggesting a normalization of zero-waste practices, while critical narratives point to concerns about greenwashing, pricing, and implementation consistency. Topic modeling further shows that zero-waste hotels are framed within broader themes, such as circular economy and carbon reduction, rather than solely operational practices. Building on these insights, the study proposes a three-layer conceptualization of digital sustainability discourse—informational, normative, and critical dimensions. By offering a conceptual perspective grounded in large-scale user-generated data, the study contributes to sustainable tourism literature and advances our understanding of how sustainability practices are socially constructed in digital contexts. Full article

Energy efficiency retrofits are widely promoted for public buildings, yet evidence from large-scale real-world projects remains limited compared with simulation-based assessments. This study leverages measured pre- and post-retrofit operational data from 530 public building retrofit projects across 11 provinces/municipalities in China to quantify realized energy-saving performance and screening-level cost-effectiveness across building types and climate zones. Wilcoxon and Kruskal–Wallis tests were employed to ensure statistical rigor. Retrofit measures were grouped into seven categories (e.g., HVAC, lighting, envelope, monitoring/management), and a median-based four-quadrant framework was employed to characterize investment–savings profiles by climate zone and building function. Across the full sample, mean energy use intensity decreased by 19.1%, with 99.2% of projects achieving positive savings. Savings varied markedly by building type: commercial and hotels achieved the highest savings intensities (26.5–28.0 kWh/(m²·a)), while education and cultural buildings generally showed lower gains, with some projects having < 10 kWh/(m²·a). Technology performance exhibited distinct climate and building suitability. Envelope retrofits were most effective in the Cold and Hot Summer–Cold Winter zones (13.30–22.06 kWh/(m²·a)) but yielded limited benefits in the Hot Summer–Warm Winter zone (~1.73 kWh/(m²·a)). HVAC and lighting upgrades delivered comparatively stable savings across climates and building types and dominated retrofit portfolios. Based on these findings, we propose a tiered strategy: prioritizing HVAC and envelope upgrades for high-load sectors while focusing on low-cost optimizations for educational facilities to mitigate investment risks. The findings provide large-scale empirical evidence to support climate- and building-specific retrofit prioritization and investment decision-making under real-world operating conditions. Full article

Accurate prediction of structural dynamic responses is critical for seismic analysis and decision-making throughout the structural life cycle. While model-driven and data-driven approaches have advanced practice, reliable prediction under limited data remains challenging due to the high cost of acquisition and simulation. This study proposes a Self-Attention-Enhanced Physics-Informed Gated Recurrent Unit network, SA-PhyGRU, for efficient and accurate seismic response prediction. The proposed network integrates GRU dynamics with a self-attention mechanism to capture long-range temporal dependencies and improve computational efficiency, while embedding physical constraints to enhance fidelity and generalization. Numerical and experimental validations on a three-story frame and a California hotel building show that SA-PhyGRU consistently outperforms conventional baselines in both accuracy and runtime, achieving improvements of up to 11.6% in $R^2,$ with pronounced gains in small-sample regimes. These results highlight SA-PhyGRU as an effective and generalizable approach for structural seismic response prediction and performance evaluation. Full article

Seismic design methods often involve high construction costs and may lead to severe structural damage during strong earthquakes. Energy dissipation technology represents an efficient approach to improving seismic performance through the integration of devices that absorb and dissipate induced seismic energy. This study investigates the seismic behavior of a five-story mixed-use hotel building with and without viscous fluid dampers through advanced numerical modeling using ETABS software, applying static, dynamic, and time-history analyses and considering representative seismic records from Ica, Peru. The research follows an applied and quantitative approach, in which two structural configurations were modeled to evaluate the efficiency of energy dissipation systems in mitigating seismic effects. The results demonstrate that the incorporation of viscous fluid dampers reduced maximum displacements by 51.12% and interstory drifts by 52.82% along the X–X axis, while absorbing approximately 74% of the induced seismic energy. All structural responses remained within safe performance limits. The findings confirm that viscous dampers substantially enhance structural seismic performance by increasing safety and functionality, and they validate their applicability as an efficient and reliable alternative for mid-rise buildings located in high-seismicity regions. Full article

Maritime transport is essential for global trade, yet ship emissions remain a major source of air pollution in coastal and port areas, with potential impacts on local air quality and human health. Cruise ships are particularly relevant in urban ports because, beyond propulsion, they require a continuous onboard energy supply for hotel services while berthed. This study develops a bottom-up emission inventory for cruise ship calls at Istanbul Galataport during the 2024 season, estimating CO₂ as a greenhouse gas (GHG) and NO_x, SO_x, and particulate matter (PM) as air-quality pollutants generated during manoeuvring and hotelling phases. Ship technical characteristics (engine type, installed main and auxiliary power, engine speed class, and year of build) were obtained from the IHS database, while port call activity data were provided by the terminal operator. Emission factors were primarily based on the IMO Third Greenhouse Gas Study and complemented with established literature sources to address missing vessel information and ensure methodological consistency. Results indicate that hotelling dominates total emissions, reflecting the high auxiliary power demand during berths. Results show that total annual emissions from 164 cruise ship calls amount to approximately 31,360 t·y⁻¹ of CO₂, 370 t·y⁻¹ of NO_x, 350 t·y⁻¹ of SO_x, and 44 t·y⁻¹ of PM. Hotelling operations account for the dominant share of emissions, contributing more than 90% of total CO₂ and the majority of NO_x and SO_x emissions, due to sustained auxiliary engine demand during berth stays. These findings confirm that cruise ship activity represents a significant localized emission source in densely populated port environments and provide a quantitative baseline for evaluating mitigation measures such as shore power, cleaner fuels, and operational strategies aimed at reducing at-berth emissions. Full article

The rapid evolution of smart building technologies has transformed the hotel industry, necessitating structured methodologies for evaluating building intelligence. This research, dedicated to engineering problems, proposes an integrated decision-making model that combines fuzzy Shannon entropy and fuzzy multi-objective optimization on the basis of ratio analysis (MOORA) to assess the intelligence level of buildings within the hospitality sector. The model systematically determines the relative importance of intelligence criteria, including engineering, environmental, economic, social and cultural, technological, and energy conservation criteria. By leveraging fuzzy Shannon entropy, the framework objectively assigns weights to criteria based on information distribution, minimizing subjective biases in evaluation. Fuzzy MOORA is then applied to rank alternative intelligent buildings in hotels, ensuring an accurate comparative assessment. The proposed model is tested on real-world hotel data, demonstrating its effectiveness in identifying optimal intelligent building configurations. The results of applying fuzzy Shannon entropy reveal that human comfort, the emission of greenhouse gases (pollution), and system integration are the most important sub-criteria. Finally, by applying the importance of the criteria in the fuzzy MOORA model, the intelligence levels of hotels are evaluated. The results show that the Parsian Kowsar, Piroozy and Sepahan Hotels are the best hotels based on the intelligent building criteria. Full article

The digital transformation of the tourism industry faces a dual challenge: the fragmentation of data across platforms and the lack of immersive “try-before-you-buy” experiences. While Large Language Models (LLMs) have revolutionized information synthesis, they typically lack real-time visual verification capabilities. This paper proposes a novel, multimodal AI Agent architecture that integrates advanced natural language planning with photorealistic 3D visualization. We present a system where a conversational agent, powered by Gemini 2.5 Flash, orchestrates a suite of dynamic tools to build structured travel itineraries (flights, hotels, activities) while simultaneously deploying a neural rendering engine. This engine utilizes a modular Structure-from-Motion (SfM) pipeline feeding into 3D Gaussian Splatting (3DGS) to render navigable, high-fidelity digital twins of hotel facilities directly within the chat interface. Positioned as a Technology Readiness Level 4 (TRL 4) proof of concept (PoC), this work demonstrates the technical feasibility of the multimodal integration between conversational logic and automated visual synthesis. The results demonstrate the technical feasibility of a pipeline that dynamically binds LLM inference to 3D spatial data, providing a foundation for high-fidelity, interactive travel consultancy. Full article

Adaptive reuse projects frequently involve substantial plan-level reorganization; however, the reconfiguration of spatial hierarchy within interior layouts remains insufficiently examined at the building scale. Background: This study investigates how spatial hierarchy is restructured during the adaptive reuse of an industrial building converted into a hotel, focusing on configurational implications of program-driven design decisions within unchanged architectural boundaries. Methods: Visibility-based Space Syntax analyses were conducted using visual integration, connectivity, and mean depth measures. Rather than relying on floor-level averages, a control-point-based comparative protocol enabled systematic pre- and post-intervention comparisons linked to plan-level architectural interventions under identical analytical parameters. Results: The findings indicate selective amplification of spatial accessibility and visual integration at defined circulation nodes on the ground floor, while upper floors exhibit contraction of visibility fields and increased relational depth. These shifts indicate a floor-specific redistribution of spatial hierarchy rather than uniform configurational transformation. Conclusions: The results suggest that spatial transformation in adaptive reuse can be interpreted as a design-driven recalibration of configurational relationships within fixed architectural boundaries. Without pursuing statistical generalisation, the study proposes a case-bound analytical protocol that may inform examination of comparable adaptive reuse contexts where program transformation occurs within stable spatial envelopes. Full article

This study provides a comprehensive empirical examination of the factors influencing the adoption of smart technologies in the Serbian hotel industry by integrating structural equation modeling (SEM), mediation and multigroup analyses, and machine-learning-based robustness testing. Grounded in the UTAUT framework, the research investigates how perceptual, organizational, and social determinants shape employees’ Behavioural Intention (BI) and actual Use Behaviour (USE). A key theoretical contribution is the introduction of the construct Perceived Spatial Impact of Technology (PST), which captures employees’ perceptions of how smart technologies transform the architectural concept, spatial organization, aesthetics, and functional logic of hotels. Although UTAUT traditionally focuses on users, neither prior studies nor the present one examine these dynamics from the perspective of architects or designers who create hotel spaces. Thus, the findings serve as an initial step from the user viewpoint, while future research should incorporate expert architectural reasoning to better understand how spatial knowledge and design logic intersect with user perceptions. All core UTAUT constructs significantly predict BI and USE, with Performance Expectancy and BI emerging as the strongest predictors across SEM and Random Forest models. PST exerts a fully mediated effect on USE through BI, and multigroup analysis reveals notable differences across job roles, hotel categories, and age groups. Overall, the results highlight that digital transformation in hospitality is not only technological and organizational, but also fundamentally architectural. Full article

This research examines high-rise hotel buildings located on the Mediterranean coast, focusing on the advantages, in terms of energy consumption and environmental benefits of installing domestic hot water (DHW) storage tanks on upper technical floors instead of in the basement. To this end, the Bali Hotel, the tallest hotel in Europe, is analyzed as a case study. The proposed system achieves a substantial reduction in energy consumption by decreasing heat losses in DHW recirculation pipes (61.3%). Annual energy costs are reduced by €8976.89, corresponding to overall DHW energy savings of 3.69%. In addition, installation costs are reduced by €15,462.18 due to the shorter recirculation pipe lengths required, which must withstand very high pressures exceeding 6 kp/cm², reaching up to 18 kp/cm². Although the initial installation cost is €15,462.18 lower, the elevated placement of the tanks increases maintenance and replacement costs. Therefore, after a 50-year service life, total construction and maintenance costs are €17,366.82 higher. This additional cost is recovered within 1.93 years, yielding cumulative savings of €527,106 over the building’s lifespan. Finally, the study quantifies the associated environmental benefits, demonstrating an annual reduction of 24,335.03 kg CO₂eq in carbon emissions, a novel contribution to the existing literature on this topic. Full article

The building sector has a significant environmental impact throughout the life cycle of a building. Reducing the environmental load of the building sector is essential for creating a sustainable society. Many current reports focus on carbon emission, while other environmental impacts remain insufficiently evaluated. Furthermore, buildings serve different functions depending on the region, and the types and quantities of primary materials used vary accordingly. Under these circumstances, little research has focused specifically on Japan. This study conducted a life cycle assessment (LCA) covering the life cycle of material inputs (structural and finishing materials) for 95 buildings in Japan. In addition to greenhouse gas emissions, multi-criteria analysis, including characterization and integration (characterization such as acidification, ozone layer destruction, and photochemical ozone; damage assessment; and integration using LIME2 and LIME3), was conducted. Based on analyses of numerous buildings, the objectives were to clarify trends in environmental impact emissions by building use, conduct an environmental impact analysis that could serve as a future benchmark, and discuss for reducing these environmental impacts. First, the analysis of trends such as maximum, median, and minimum values across six building types revealed that the environmental impact per square meter tended to be lower for production and logistics facilities and higher for offices, government buildings, schools, hospitals, hotels, and condominiums across many indicators. However, significant variations were observed between individual buildings within each category. These results can serve as a benchmark for the environmental impact of future buildings in Japan. Next, GHG emissions and integration (LIME2, LIME3) were quantitatively identified for materials with high emissions, and the factors were considered. Furthermore, processes with high environmental impacts associated with the material were analyzed and identified. Ready-mixed concrete, reinforcing bars, and steel frames showed high values across quantitative indicators, whereas wood and other materials varied by indicator. Finally, based on these findings, perspectives for reducing the environmental impact of key materials are proposed for each stakeholder group. Full article

This study presents an integrated engineering methodology aligned with the planning phase of the ISO 50001:2018 (Energy Management Systems—Requirements with Guidance for Use. International Organization for Standardization (ISO): Geneva, Switzerland, 2018) energy management standard for the design, sizing, and assessment of a solar thermal system applied to domestic hot water production in a medium-scale hotel building. The proposed framework focuses on the energy review stage of ISO 50001, incorporating site-specific climatic assessment, spatial layout optimization, structural feasibility analysis, and energy performance evaluation to support informed technology selection and system viability. Thermal performance is assessed using real operational data from the case study, complemented by a data-driven multivariable regression-based energy performance indicator (EnPI) that relates electricity consumption to cooling degree days and room occupancy. This regression model, developed in accordance with ISO 50001 recommendations, enables transparent monitoring of energy performance under real operating conditions without relying on black-box predictive techniques. Material selection criteria for absorber plates, heat-transfer components, transparent covers, and insulation layers are discussed to support both initial efficiency and performance stability under site-specific climatic conditions. In addition, an indicative and qualitative analysis of material-dependent performance evolution is introduced to support comparative decision-making, without implying quantitative lifetime prediction. Structural feasibility of the collector support system is examined through finite-element simulations under combined gravitational and wind loads, providing illustrative verification of stress distribution under representative operating conditions. The installed system delivers an annual thermal energy contribution of 8468 kWh, resulting in an estimated reduction of 7.79 t of CO₂ emissions per year. Economic indicators suggest a short payback period and a favorable internal rate of return, which should be interpreted as order-of-magnitude estimates within the planning scope of the methodology. Overall, the proposed methodology provides a replicable and multidisciplinary planning-phase framework aligned with ISO 50001 for the design and assessment of solar thermal systems in medium-scale buildings under real operating conditions. Full article

Firms increasingly develop dynamic pricing policies to maximize revenue for perishable products with limited inventory over a finite selling horizon. This trend is enabled by the growing availability of sales data and is observed across industries such as airlines, hotels, cruise lines, fashion, and seasonal retail. Given customer heterogeneity, firms may further adopt discriminatory pricing across customer groups. However, excessive price disparities can trigger legal risks and consumer backlash, motivating price fairness constraints that bound inter-group price differences in each selling period. We formulate this problem as an action-constrained Markov decision process (ACMDP) with unknown demand functions and adopt a model-free deep reinforcement learning (DRL) framework. However, standard DRL algorithms for unconstrained MDPs cannot directly handle these fairness constraints. Therefore, we introduce an optimization-based shielding mechanism. From the DRL pricing agent’s perspective, this mechanism converts the ACMDP into a shield-induced unconstrained MDP. Meanwhile, it guarantees constraint satisfaction for all executed prices. Building on this framework, we propose the Shield Soft Actor-Critic (Shield-SAC) algorithm. This is the first Shield-SAC method for fairness-aware pricing under instantaneous and hard price fairness constraints. We test it in two simulated markets of different scales and validate that Shield-SAC achieves strong revenue performance while consistently enforcing the price fairness constraints during both training and deployment. Full article

The revised Energy Performance of Buildings Directive (EPBD) has introduced ambitious targets aimed at accelerating the decarbonization of the building sector. In parallel, the forthcoming implementation of the Emission Trading System for buildings and road transport (ETS2) in January 2027 adds a further dimension to the policy landscape. This study investigates three renewable energy retrofit strategies (Scenarios A, B, and C) for a hotel building in northern Italy, assessing their effectiveness in meeting the decarbonization objectives set by the EPBD and ETS2. Scenario A couples photovoltaic generation with an existing gas boiler, Scenario B integrates PV with an electric heat pump for space heating, and Scenario C implements the full electrification of both heating and domestic hot water. The results of the three scenarios are evaluated using selected metrics, such as renewable primary energy consumption (EPren), non-renewable primary energy consumption (EPnren), CO₂ emission (CO₂), carbon avoidance cost (CAC), levelized cost of energy (LCOE), net present value (NPV), and Emission Trading System (ETS)2. The results show that PV deployment alone provides economic benefits but yields limited reductions in CO₂ emissions and non-renewable primary energy consumption due to continued reliance on natural gas. The introduction of a heat pump significantly enhances environmental performance, with reduced fossil fuel consumption, increased renewable energy use, and improved cost-effectiveness of carbon avoidance. The ETS2 has no impact in the case of full electrification, as fossil fuel consumption is completely eliminated. Full electrification achieves the greatest emission reductions and the lowest non-renewable primary energy demand while offering the strongest long-term economic performance. Overall, the analysis demonstrates that combining PV systems with building electrification is essential to achieving deep decarbonization, and that fully electrified configurations present the most robust pathway for compliance with emerging ETS2 policies. Full article