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Keywords = demand control ventilation

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15 pages, 286 KiB  
Review
Strategies for Maximising Lung Utilisation in Donors After Brain and Cardiac Death: A Narrative Review
by Carola Pergolizzi, Chiara Lazzeri, Daniele Marianello, Cesare Biuzzi, Casagli Irene, Antonella Puddu, Elena Bargagli, David Bennett, Chiara Catelli, Luca Luzzi, Francesca Montagnani, Francisco Del Rio Gallegos, Sabino Scolletta, Adriano Peris and Federico Franchi
J. Clin. Med. 2025, 14(15), 5380; https://doi.org/10.3390/jcm14155380 - 30 Jul 2025
Abstract
Lung transplantation remains the standard of care for end-stage lung disease, yet a persistent gap exists between donor lung availability and growing clinical demand. Expanding the donor pool and optimising donor lung management are therefore critical priorities. However, no universally accepted management protocols [...] Read more.
Lung transplantation remains the standard of care for end-stage lung disease, yet a persistent gap exists between donor lung availability and growing clinical demand. Expanding the donor pool and optimising donor lung management are therefore critical priorities. However, no universally accepted management protocols are currently in place. This narrative review examines evidence-based strategies to improve lung utilisation across three donor categories: donors after brain death (DBD), controlled donors after circulatory death (cDCD), and uncontrolled donors after circulatory death (uDCD). A systematic literature search was conducted to identify interventions targeting lung preservation and function, including protective ventilation, recruitment manoeuvres, fluid and hormonal management, and ex vivo lung perfusion (EVLP). Distinct pathophysiological mechanisms—sympathetic storm and systemic inflammation in DBD, ischaemia–reperfusion injury in cDCD, and prolonged warm ischaemia in uDCD—necessitate tailored approaches to lung preservation. In DBD donors, early application of protective ventilation, bronchoscopy, and infection surveillance is essential. cDCD donors benefit from optimised pre- and post-withdrawal management to mitigate lung injury. uDCD donor lungs, uniquely vulnerable to ischaemia, require meticulous post-mortem evaluation and preservation using EVLP. Implementing structured, evidence-based lung management strategies can significantly enhance donor lung utilisation and expand the transplantable organ pool. The integration of such practices into clinical protocols is vital to addressing the global shortage of suitable lungs for transplantation. Full article
(This article belongs to the Section Respiratory Medicine)
13 pages, 1479 KiB  
Article
Asymmetric Spread Analysis of Heart Rate Variability in XC Mountain Biking During a 20-Minute Autonomic Profile Test
by Luis Javier Tafur-Tascón, María José Martínez-Patiño and Yecid Mina-Paz
Sensors 2025, 25(15), 4677; https://doi.org/10.3390/s25154677 - 29 Jul 2025
Viewed by 117
Abstract
The heart is innervated by the autonomic nervous system (ANS), which plays a role in regulating the heart rate. Cross-country mountain biking (MTBXC) is a sport with high physiological demands, where the autonomic nervous system plays a significant role. The main objective of [...] Read more.
The heart is innervated by the autonomic nervous system (ANS), which plays a role in regulating the heart rate. Cross-country mountain biking (MTBXC) is a sport with high physiological demands, where the autonomic nervous system plays a significant role. The main objective of this study was to analyze the asymmetry of heart rate in Colombian National Team mountain bikers, sub-23 category, during a 20 min cardiovascular autonomic profile test. Method: The cardiovascular autonomic profile was measured through heart rate variability during a 20 min test, divided into eight phases (supine, controlled ventilation at 10 cycles/min, controlled ventilation at 12 cycles/min, postural change, orthostasis, Ruffier test, 1 min recovery, and final recovery) in a group of n = 10 MTB cyclists from the National Sub-23 Team, including 5 males and 5 females. Results: The results for the male athletes were as follows: age: 19 ± 1 years; VO2max: 67.5 mL/kg/min; max power: 355 W; HRmax: 204 bpm. The results for the female athletes were as follows: age: 19 ± 1 years; VOmax: 58.5 mL/kg/min; max power: 265 W; HRmax: 194 bpm. Both genders showed the expected autonomic behavior in each phase. Asymmetrical propagation of heart rate was observed, with a greater deceleration pattern after postural changes and effort and a symmetrical acceleration pattern in these two phases. Discussion: Athletes exhibit increased vagal response compared to non-athletes. Mountain bikers show rapid heart rate reduction after exertion. Conclusion: This study demonstrates how mountain bikers exhibit increased heart rate deceleration following sympathetic stimuli. Full article
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21 pages, 1558 KiB  
Article
Total Performance in Practice: Energy Efficiency in Modern Developer-Built Housing
by Wiktor Sitek, Michał Kosakiewicz, Karolina Krysińska, Magdalena Daria Vaverková and Anna Podlasek
Energies 2025, 18(15), 4003; https://doi.org/10.3390/en18154003 - 28 Jul 2025
Viewed by 167
Abstract
Improving the energy efficiency of residential buildings is essential for achieving global climate goals and reducing environmental impact. This study analyzes the Total Performance approach using the example of a modern semi-detached house built by a Polish developer, as an example. The building [...] Read more.
Improving the energy efficiency of residential buildings is essential for achieving global climate goals and reducing environmental impact. This study analyzes the Total Performance approach using the example of a modern semi-detached house built by a Polish developer, as an example. The building is designed with integrated systems that minimize energy consumption while maintaining resident comfort. The building is equipped with an air-to-water heat pump, underfloor heating, mechanical ventilation with heat recovery, and automatic temperature control systems. Energy efficiency was assessed using ArCADia–TERMOCAD 8.0 software in accordance with Polish Technical Specifications (TS) and verified by monitoring real-time electricity consumption during the heating season. The results show a PED from non-renewable sources of 54.05 kWh/(m2·year), representing a 23% reduction compared to the Polish regulatory limit of 70 kWh/(m2·year). Real-time monitoring conducted from December 2024 to April 2025 confirmed these results, indicating an actual energy demand of approximately 1771 kWh/year. Domestic hot water (DHW) preparation accounted for the largest share of energy consumption. Despite its dependence on grid electricity, the building has the infrastructure to enable future photovoltaic (PV) installation, offering further potential for emissions reduction. The results confirm that Total Performance strategies are not only compliant with applicable standards, but also economically and environmentally viable. They represent a scalable model for sustainable residential construction, in line with the European Union’s (EU’s) decarbonization policy and the goals of the European Green Deal. Full article
(This article belongs to the Section G: Energy and Buildings)
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39 pages, 5325 KiB  
Review
Mechanical Ventilation Strategies in Buildings: A Comprehensive Review of Climate Management, Indoor Air Quality, and Energy Efficiency
by Farhan Lafta Rashid, Mudhar A. Al-Obaidi, Najah M. L. Al Maimuri, Arman Ameen, Ephraim Bonah Agyekum, Atef Chibani and Mohamed Kezzar
Buildings 2025, 15(14), 2579; https://doi.org/10.3390/buildings15142579 - 21 Jul 2025
Viewed by 549
Abstract
As the demand for energy-efficient homes continues to rise, the importance of advanced mechanical ventilation systems in maintaining indoor air quality (IAQ) has become increasingly evident. However, challenges related to energy balance, IAQ, and occupant thermal comfort persist. This review examines the performance [...] Read more.
As the demand for energy-efficient homes continues to rise, the importance of advanced mechanical ventilation systems in maintaining indoor air quality (IAQ) has become increasingly evident. However, challenges related to energy balance, IAQ, and occupant thermal comfort persist. This review examines the performance of mechanical ventilation systems in regulating indoor climate, improving air quality, and minimising energy consumption. The findings indicate that demand-controlled ventilation (DCV) can enhance energy efficiency by up to 88% while maintaining CO2 concentrations below 1000 ppm during 76% of the occupancy period. Heat recovery systems achieve efficiencies of nearly 90%, leading to a reduction in heating energy consumption by approximately 19%. Studies also show that employing mechanical rather than natural ventilation in schools lowers CO2 levels by 20–30%. Nevertheless, occupant misuse or poorly designed systems can result in CO2 concentrations exceeding 1600 ppm in residential environments. Hybrid ventilation systems have demonstrated improved thermal comfort, with predicted mean vote (PMV) values ranging from –0.41 to 0.37 when radiant heating is utilized. Despite ongoing technological advancements, issues such as system durability, user acceptance, and adaptability across climate zones remain. Smart, personalized ventilation strategies supported by modern control algorithms and continuous monitoring are essential for the development of resilient and health-promoting buildings. Future research should prioritize the integration of renewable energy sources and adaptive ventilation controls to further optimise system performance. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
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28 pages, 2612 KiB  
Article
Optimizing Economy with Comfort in Climate Control System Scheduling for Indoor Ice Sports Venues’ Spectator Zones Considering Demand Response
by Zhuoqun Du, Yisheng Liu, Yuyan Xue and Boyang Liu
Algorithms 2025, 18(7), 446; https://doi.org/10.3390/a18070446 - 20 Jul 2025
Viewed by 165
Abstract
With the growing popularity of ice sports, indoor ice sports venues are drawing an increasing number of spectators. Maintaining comfort in spectator zones presents a significant challenge for the operational scheduling of climate control systems, which integrate ventilation, heating, and dehumidification functions. To [...] Read more.
With the growing popularity of ice sports, indoor ice sports venues are drawing an increasing number of spectators. Maintaining comfort in spectator zones presents a significant challenge for the operational scheduling of climate control systems, which integrate ventilation, heating, and dehumidification functions. To explore economic cost potential while ensuring user comfort, this study proposes a demand response-integrated optimization model for climate control systems. To enhance the model’s practicality and decision-making efficiency, a two-stage optimization method combining multi-objective optimization algorithms with the technique for order preference by similarity to an ideal solution (TOPSIS) is proposed. In terms of algorithm comparison, the performance of three typical multi-objective optimization algorithms—NSGA-II, standard MOEA/D, and Multi-Objective Brown Bear Optimization (MOBBO)—is systematically evaluated. The results show that NSGA-II demonstrates the best overall performance based on evaluation metrics including runtime, HV, and IGD. Simulations conducted in China’s cold regions show that, under comparable comfort levels, schedules incorporating dynamic tariffs are significantly more economically efficient than those that do not. They reduce operating costs by 25.3%, 24.4%, and 18.7% on typical summer, transitional, and winter days, respectively. Compared to single-objective optimization approaches that focus solely on either comfort enhancement or cost reduction, the proposed multi-objective model achieves a better balance between user comfort and economic performance. This study not only provides an efficient and sustainable solution for climate control scheduling in energy-intensive buildings such as ice sports venues but also offers a valuable methodological reference for energy management and optimization in similar settings. Full article
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35 pages, 2895 KiB  
Review
Ventilated Facades for Low-Carbon Buildings: A Review
by Pinar Mert Cuce and Erdem Cuce
Processes 2025, 13(7), 2275; https://doi.org/10.3390/pr13072275 - 17 Jul 2025
Viewed by 580
Abstract
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding [...] Read more.
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding and the insulated structure, address that challenge. First, the paper categorises VFs by structural configuration, ventilation strategy and functional control into four principal families: double-skin, rainscreen, hybrid/adaptive and active–passive systems, with further extensions such as BIPV, PCM and green-wall integrations that couple energy generation or storage with envelope performance. Heat-transfer analysis shows that the cavity interrupts conductive paths, promotes buoyancy- or wind-driven convection, and curtails radiative exchange. Key design parameters, including cavity depth, vent-area ratio, airflow velocity and surface emissivity, govern this balance, while hybrid ventilation offers the most excellent peak-load mitigation with modest energy input. A synthesis of simulation and field studies indicates that properly detailed VFs reduce envelope cooling loads by 20–55% across diverse climates and cut winter heating demand by 10–20% when vents are seasonally managed or coupled with heat-recovery devices. These thermal benefits translate into steadier interior surface temperatures, lower radiant asymmetry and fewer drafts, thereby expanding the hours occupants remain within comfort bands without mechanical conditioning. Climate-responsive guidance emerges in tropical and arid regions, favouring highly ventilated, low-absorptance cladding; temperate and continental zones gain from adaptive vents, movable insulation or PCM layers; multi-skin adaptive facades promise balanced year-round savings by re-configuring in real time. Overall, the review demonstrates that VFs constitute a versatile, passive-plus platform for low-carbon buildings, simultaneously enhancing energy efficiency, durability and indoor comfort. Future advances in smart controls, bio-based materials and integrated energy-recovery systems are poised to unlock further performance gains and accelerate the sector’s transition to net-zero. Emerging multifunctional materials such as phase-change composites, nanostructured coatings, and perovskite-integrated systems also show promise in enhancing facade adaptability and energy responsiveness. Full article
(This article belongs to the Special Issue Sustainable Development of Energy and Environment in Buildings)
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13 pages, 683 KiB  
Article
Breathing Reserve and Lung Function in Female Elite Runners
by Ferdinand Grov Kyte, Karoline Holsen Kyte, Linn Skinstad, Jonny Hisdal and Trine Stensrud
Sports 2025, 13(7), 231; https://doi.org/10.3390/sports13070231 - 14 Jul 2025
Viewed by 253
Abstract
Breathing reserve (BR) is the remaining proportion of achievable minute ventilation that remains unutilized at total exhaustion during exercise. Previous studies have found a smaller BR in endurance-trained athletes compared to untrained controls. However, most of these studies have examined men. Given that [...] Read more.
Breathing reserve (BR) is the remaining proportion of achievable minute ventilation that remains unutilized at total exhaustion during exercise. Previous studies have found a smaller BR in endurance-trained athletes compared to untrained controls. However, most of these studies have examined men. Given that women have a greater ventilatory limitation than stature-matched men, the present cross-sectional study aimed to investigate how this sex difference influences BR and lung function tests in endurance-trained females compared to matched, untrained females. To obtain further insight, we also aimed to investigate whether VO2max serves as a predictor of BR. We examined 15 female elite runners and 15 healthy, matched female controls aged 24–33 years with regard to pulmonary function, MVV, VEmax, BR, and VO2max. The elite runner group had a median BR of 5%, while that of the controls was 21%, representing a significant difference. Lung function tests showed no differences between the two groups. A moderate association was found between VO2max and BR. The female elite runners demonstrated a lower BR than the group of matched, untrained controls, which was lower than that found for male elite athletes in previous studies. This may indicate a greater ventilatory demand in female relative to male endurance athletes. Full article
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37 pages, 3802 KiB  
Review
Energy Efficiency Optimization of Air Conditioning Systems Towards Low-Carbon Cleanrooms: Review and Future Perspectives
by Xinran Zeng, Chunhui Li, Xiaoying Li, Chennan Mao, Zhengwei Li and Zhenhai Li
Energies 2025, 18(13), 3538; https://doi.org/10.3390/en18133538 - 4 Jul 2025
Viewed by 664
Abstract
The advancement of high-tech industries, notably in semiconductor manufacturing, pharmaceuticals, and precision instrumentation, has imposed stringent requirements on cleanroom environments, where strict control of airborne particulates, microbial presence, temperature, and humidity is essential. However, these controlled environments incur significant energy consumption, with air [...] Read more.
The advancement of high-tech industries, notably in semiconductor manufacturing, pharmaceuticals, and precision instrumentation, has imposed stringent requirements on cleanroom environments, where strict control of airborne particulates, microbial presence, temperature, and humidity is essential. However, these controlled environments incur significant energy consumption, with air conditioning systems accounting for 40–60% of total usage due to high air circulation rates, intensive treatment demands, and system resistance. In light of global carbon reduction goals and escalating energy costs, improving the energy efficiency of cleanroom heating, ventilation, and air conditioning (HVAC) systems has become a critical research priority. Recent efforts have focused on optimizing airflow distribution, integrating heat recovery technologies, and adopting low-resistance filtration to reduce energy demand while maintaining stringent environmental standards. Concurrently, artificial intelligence (AI) methods, such as machine learning, deep learning, and adaptive control, are being employed to enable intelligent, energy-efficient system operations. This review systematically examines current energy-saving technologies and strategies in cleanroom HVAC systems, assesses their real-world performance, and highlights emerging trends. The objective is to provide a scientific basis for the green design, operation, and retrofit of cleanrooms, thereby supporting the industry’s transition toward low-carbon, sustainable development. Full article
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13 pages, 3164 KiB  
Article
The Steady-State and Dynamic Characteristics of a Humidity-Sensitive Air Inlet: Modeling Based on Measurements
by Maciej Mijakowski and Piotr Narowski
Energies 2025, 18(13), 3444; https://doi.org/10.3390/en18133444 - 30 Jun 2025
Viewed by 201
Abstract
This paper presents the airflow characteristics of humidity-sensitive air inlet. This type of air inlets and exhausts are often part of demand control ventilation, especially in dwellings where humidity is an important indicator of ventilation needs. Humidity-controlled ventilation is one of the simplest [...] Read more.
This paper presents the airflow characteristics of humidity-sensitive air inlet. This type of air inlets and exhausts are often part of demand control ventilation, especially in dwellings where humidity is an important indicator of ventilation needs. Humidity-controlled ventilation is one of the simplest implementations of smart ventilation, even in the case of a natural ventilation system. This type of solution leads to decreased energy consumption and increases the indoor air quality. A description of airflow characteristics is crucial for resolving these issues. The presented characteristics are based on the measurements of the indoor/outdoor relative humidity, airflow, and pressure drop across the air inlet. The characteristics are described based on a general power law flow model (V = C·∆pn), which is the most suitable, for example, for the CONTAM multizone indoor air quality and ventilation analysis computer program. The characteristics include relationships between the indoor and outdoor relative humidity, hysteresis, and dynamic changes in indoor relative humidity. The simplified and complex formulas are presented. The accuracy of the airflow calculation based on these formulas is discussed. Full article
(This article belongs to the Section G: Energy and Buildings)
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33 pages, 582 KiB  
Review
An Overview of State-of-the-Art Research on Smart Building Systems
by S. M. Mahfuz Alam and Mohd. Hasan Ali
Electronics 2025, 14(13), 2602; https://doi.org/10.3390/electronics14132602 - 27 Jun 2025
Viewed by 466
Abstract
Smart buildings require an energy management system that can meet inhabitants’ demands with a reduced amount of energy consumed by the heating ventilation and air-conditioning system (HVAC), as well as the lighting and shading systems. This work provides a detailed review of available [...] Read more.
Smart buildings require an energy management system that can meet inhabitants’ demands with a reduced amount of energy consumed by the heating ventilation and air-conditioning system (HVAC), as well as the lighting and shading systems. This work provides a detailed review of available methods proposed in the literature for effective control of automated systems such as HVAC, lighting, shading, etc. Moreover, effective forecasting of renewable energy generations and loads, scheduling of loads, and efficient operations of thermal and electric energy storage are crucial elements for energy management systems for ensuring reliability and stability. In this work, these aspects of energy management systems, that have been popular over the last ten years, are analyzed. In addition, the development of internet-of-things (IoT)-based sensors widens the artificial intelligence (AI) and machine learning applications in smart buildings. However, this system can be vulnerable against cyber-attacks. The state of the art of AI and machine learning applications along with cyber security issues and solutions for smart building systems are discussed. Finally, some recommendations for future research trends and directions on smart building systems are provided. This work will provide a basic guideline and will also be very useful to researchers in the area of smart building systems in the future. Full article
(This article belongs to the Section Industrial Electronics)
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18 pages, 461 KiB  
Article
Online Song Intervention Program to Cope with Work Distress of Remote Dispatched Workers: Music for an Adaptive Environment in the Hyperconnected Era
by Yaming Wei and Hyun Ju Chong
Behav. Sci. 2025, 15(7), 869; https://doi.org/10.3390/bs15070869 - 26 Jun 2025
Viewed by 244
Abstract
With the increasing demands of long-term overseas assignments, workers in isolated environments, such as maritime crews, often experience heightened psychological stress and a lack of accessible emotional support. This study investigates the effectiveness of online song intervention program based on contextual support model [...] Read more.
With the increasing demands of long-term overseas assignments, workers in isolated environments, such as maritime crews, often experience heightened psychological stress and a lack of accessible emotional support. This study investigates the effectiveness of online song intervention program based on contextual support model in reducing work-related distress and enhancing psychological resilience among the ship crews dispatched for an extensive period for work. Eighteen overseas workers participated in a four-week intervention that included both individual and group sessions, where they engaged with songs to cultivate personal and interpersonal resources. A deductive content analysis following the intervention revealed 3 main categories, 6 generic categories, and 14 subcategories. The three main categories identified were relationships, autonomy, and mood regulation. The relationships category encompassed support systems and bonding, focusing on empathy, consolation, positive perspective, vicarious empowerment, trust, and changes of perspective. Autonomy involved fostering a sense of control and fulfillment through determination, anticipation, motivation, and achievement. Mood regulation was divided into grounding and emotional resolution, which included containment, sedation, externalization, and ventilation. The findings highlight that song lyrics offer valuable insights for developing resources aimed at mood regulation, social support, and self-efficacy, helping to alleviate work-related stress during dispatch periods. Songs also foster a sense of control, competence, and relational connectedness, with mood regulation emerging as a key feature of their emotional impact. These results suggest that incorporating songs with lyrics focused on personal and interpersonal resources could be an effective strategy to support remotely dispatched workers. Furthermore, this approach appears to be a viable and scalable solution for online programs. Full article
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28 pages, 5769 KiB  
Article
Assessment and Enhancement of Indoor Environmental Quality in a School Building
by Ronan Proot-Lafontaine, Abdelatif Merabtine, Geoffrey Henriot and Wahid Maref
Sustainability 2025, 17(12), 5576; https://doi.org/10.3390/su17125576 - 17 Jun 2025
Viewed by 444
Abstract
Achieving both indoor environmental quality (IEQ) and energy efficiency in school buildings remains a challenge, particularly in older structures where renovation strategies often lack site-specific validation. This study evaluates the impact of energy retrofits on a 1970s primary school in France by integrating [...] Read more.
Achieving both indoor environmental quality (IEQ) and energy efficiency in school buildings remains a challenge, particularly in older structures where renovation strategies often lack site-specific validation. This study evaluates the impact of energy retrofits on a 1970s primary school in France by integrating in situ measurements with a validated numerical model for forecasting energy demand and IEQ. Temperature, humidity, and CO2 levels were recorded before and after renovations, which included insulation upgrades and an air handling unit replacement. Results indicate significant improvements in winter thermal comfort (PPD < 20%) with a reduced heating water temperature (65 °C to 55 °C) and stable indoor air quality (CO2 < 800 ppm), without the need for window ventilation. Night-flushing ventilation proved effective in mitigating overheating by shifting peak temperatures outside school hours, contributing to enhanced thermal regulation. Long-term energy consumption analysis (2019–2022) revealed substantial reductions in gas and electricity use, 15% and 29% of energy saving for electricity and gas, supporting the effectiveness of the applied renovation strategies. However, summer overheating (up to 30 °C) persisted, particularly in south-facing upper floors with extensive glazing, underscoring the need for additional optimization in solar gain management and heating control. By providing empirical validation of renovation outcomes, this study bridges the gap between theoretical predictions and real-world effectiveness, offering a data-driven framework for enhancing IEQ and energy performance in aging school infrastructure. Full article
(This article belongs to the Special Issue New Insights into Indoor Air Quality in Sustainable Buildings)
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20 pages, 1482 KiB  
Article
Research on Person Pose Estimation Based on Parameter Inverted Pyramid and High-Dimensional Feature Enhancement
by Guofeng Ma and Qianyi Zhang
Symmetry 2025, 17(6), 941; https://doi.org/10.3390/sym17060941 - 13 Jun 2025
Viewed by 678
Abstract
Heating, Ventilation and Air Conditioning (HVAC) systems are significant carbon emitters in buildings, and precise regulation is crucial for achieving carbon neutrality. Computer vision-based occupant behavior prediction provides vital data for demand-driven control strategies. Real-time multi-person pose estimation faces challenges in balancing speed [...] Read more.
Heating, Ventilation and Air Conditioning (HVAC) systems are significant carbon emitters in buildings, and precise regulation is crucial for achieving carbon neutrality. Computer vision-based occupant behavior prediction provides vital data for demand-driven control strategies. Real-time multi-person pose estimation faces challenges in balancing speed and accuracy, especially in complex environments. Traditional top-down methods become computationally expensive as the number of people increases, while bottom-up methods struggle with key point mismatches in dense crowds. This paper introduces the Efficient-RTMO model, which leverages the Parameter Inverted Image Pyramid (PIIP) with hierarchical multi-scale symmetry for lightweight processing of high-resolution images and a deeper network for low-resolution images. This approach reduces computational complexity, particularly in dense crowd scenarios, and incorporates a dynamic sparse connectivity mechanism via the star-shaped dynamic feed-forward network (StarFFN). By optimizing the symmetry structure, it improves inference efficiency and ensures effective feature fusion. Experimental results on the COCO dataset show that Efficient-RTMO outperforms the baseline RTMO model, achieving more than 2× speed improvement and a 0.3 AP increase. Ablation studies confirm that PIIP and StarFFN enhance robustness against occlusions and scale variations, demonstrating their synergistic effectiveness. Full article
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22 pages, 4567 KiB  
Article
Thermodynamic-Based Perceived Predictive Power Control for Renewable Energy Penetrated Resident Microgrids
by Wenhui Shi, Lifei Ma, Wenxin Li, Yankai Zhu, Dongliang Nan and Yinzhang Peng
Energies 2025, 18(12), 3027; https://doi.org/10.3390/en18123027 - 6 Jun 2025
Viewed by 444
Abstract
Heating, ventilation, and air conditioning (HVAC) systems and microgrids have garnered significant attention in recent research, with temperature control and renewable energy integration emerging as key focus areas in urban distribution power systems. This paper proposes a robust predictive temperature control (RPTC) method [...] Read more.
Heating, ventilation, and air conditioning (HVAC) systems and microgrids have garnered significant attention in recent research, with temperature control and renewable energy integration emerging as key focus areas in urban distribution power systems. This paper proposes a robust predictive temperature control (RPTC) method and a microgrid control strategy incorporating asymmetrical challenges, including uneven power load distribution and uncertainties in renewable outputs. The proposed method leverages a thermodynamics-based R-C model to achieve precise indoor temperature regulation under external disturbances, while a multisource disturbance compensation mechanism enhances system robustness. Additionally, an HVAC load control model is developed to enable real-time dynamic regulation of airflow, facilitating second-level load response and improved renewable energy accommodation. A symmetrical power tracking and voltage support secondary controller is also designed to accurately capture and manage the fluctuating power demands of HVAC systems for supporting operations of distribution power systems. The effectiveness of the proposed method is validated through power electronics simulations in the Matlab/Simulink/SimPowerSystems environment, demonstrating its practical applicability and superior performance. Full article
(This article belongs to the Special Issue Digital Modeling, Operation and Control of Sustainable Energy Systems)
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13 pages, 1461 KiB  
Article
Experimental Assessment of Demand-Controlled Ventilation Strategies for Energy Efficiency and Indoor Air Quality in Office Spaces
by Behrang Chenari, Shiva Saadatian and Manuel Gameiro da Silva
Air 2025, 3(2), 17; https://doi.org/10.3390/air3020017 - 4 Jun 2025
Viewed by 726
Abstract
This study investigates the performance of different demand-controlled ventilation strategies for improving indoor air quality while optimizing energy efficiency. The experimental research was conducted at the Indoor Live Lab at the University of Coimbra using a smart window equipped with mechanical ventilation boxes, [...] Read more.
This study investigates the performance of different demand-controlled ventilation strategies for improving indoor air quality while optimizing energy efficiency. The experimental research was conducted at the Indoor Live Lab at the University of Coimbra using a smart window equipped with mechanical ventilation boxes, occupancy sensors, and a real-time CO2 monitoring system. Several occupancy-based and CO2-based ventilation control strategies were implemented and tested to dynamically adjust ventilation rates according to real-time indoor conditions, including (1) occupancy period-based control, (2) occupancy level-based control, (3) ON-OFF CO₂-based control, (4) multi-level CO₂-based control, and (5) modulating CO₂-based control. The results indicate that intelligent control strategies can significantly reduce energy consumption while maintaining indoor air quality within acceptable limits. Among the CO₂-based controls, strategy 5 achieved optimal performance, reducing energy consumption by 60% compared to the simple ON-OFF strategy, while maintaining satisfactory indoor air quality. Regarding occupancy-based strategies, strategy 2 showed 58% energy savings compared to the simple occupancy period-based control, but with greater CO₂ concentration fluctuation. The results demonstrate that intelligent DCV systems can simultaneously reduce ventilation energy use by 60% and maintain compliant indoor air quality levels, with modulating CO₂-based control proving most effective. The findings highlight the potential of integrating sensor-based ventilation controls in office spaces to achieve energy savings, enhance occupant comfort, and contribute to the development of smarter, more sustainable buildings. Future research should explore the integration of predictive analytics and multi-pollutant sensing to further optimize demand-controlled ventilation performance. Full article
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