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Measurement of housing IEQ and occupant thermal comfort when working from home during summer and winter
No full textAs hybrid work arrangements become widespread, understanding the indoor environmental quality (IEQ) of home workspaces has become increasingly important. Although numerous studies have investigated IEQ in office settings, research on IEQ in home workspaces remains limited. This study aims to address that gap by examining the thermal environment in home workspaces through a combination of physical measurements of indoor temperature and humidity and occupant surveys on thermal comfort. A field survey was conducted during both summer and winter; valid samples were collected from 60 participants in summer and 190 in winter. This is one of the largest studies worldwide to investigate the home workspace environment including physical environmental measurements. The results showed that the indoor thermal environments of home workspaces varied widely compared with those in offices, with summer temperatures averaging 27.2 ± 1.6°C and winter temperatures averaging 20.1 ± 3.6°C. Despite this variation, average thermal satisfaction remained slightly positive in both seasons. Neutral temperatures were estimated at 27.5°C in summer and 21.4°C in winter, although no reliable neutral humidity value could be identified. These findings provide important implications for improving thermal comfort and productivity in home workspace environments
Commercial Rental Office Building with Developed Convection and Radiant Air Conditioning Systems for Enhanced Comfort and Energy Efficiency
No full textThis paper presents an environmentally conscious commercial rental office building in Tokyo featuring a unique architectural design with stairwells integrated into the façade. These stairwells contribute to year-round energy savings in air conditioning by serving multiple functions: acting as natural ventilation shafts through the chimney effect during intermediate seasons, as a double-skin façade in summer, and as sunrooms in winter. Two energy-efficient air conditioning systems—one convection-based and one radiant—were developed and installed on identically designed floors, allowing for direct comparison in terms of energy performance and occupant comfort. Both systems maintain a standard ceiling height of 2800 mm within a reduced overall floor height of 3450 mm (compared to the typical 4000 mm), enabling the addition of an extra floor and expanding the rentable area within local height limits. The convection system uses variable airflow and exploits the Coanda effect to distribute air evenly without ductwork, reducing fan power consumption by 83%. The radiant system employs variable temperature and water flow control to optimize free cooling, even at outdoor temperatures near 30°C. This system achieved a coefficient of performance (COP) of 8.1 when using high-temperature chilled water
Decarbonization approaches of Kyoto City Hall Buildings
No full textThis is a project to renovate the city hall building in Kyoto, the ancient capital and metropolis of Japan. The main building, which has historical architectural value, will be made more earthquake resistant, and the building frame will continue to be used. The new annex building to be constructed on an adjacent site is characterized by its high-density office space with a reduced story height under the height regulation to maintain the traditional landscape of Kyoto. The purpose of this study is to plan and analyse a group of city hall buildings with low energy consumption that is appropriate for the environmental city of Kyoto, taking different approaches to decarbonization for the main building to be renovated and the annex building to be newly built. This paper mainly reports on the planning and analysis of energy conservation measures for the newly constructed annex building. The primary energy consumption of the branch office building was reduced by 66% (actual results in 2023) compared to the standard building
A Seq2Seq Framework for Spatiotemporal Forecasting in Ventilation Systems
No full textRapid acquisition of flow field data is of significant importance in both scientific and engineering contexts. However, conventional computational fluid dynamics (CFD) methods require substantial computational resources and time to obtain high-resolution flow field information, particularly in transient scenarios. Deep neural networks (DNNs), by leveraging their strengths in solving nonlinear problems and bypassing the numerical iteration of governing physical equations, offer distinct advantages for large-scale flow field data acquisition. This paper proposes a sequence-to-sequence model for transient flow field prediction, incorporating an attention mechanism, to forecast future flow field states. The model employs a graph-based structure to accommodate unstructured data. It first encodes a known input sequence to extract latent representations, which are then decoded along with the flow field state from the previous time step to predict subsequent sequences. Results demonstrate that in two- dimensional cases, the trained model achieves a prediction error of approximately 3% for future flow sequences while significantly accelerating inference speed. This approach enables rapid estimation of dynamically changing flow fields in indoor environments, providing valuable references for ventilation research
Performance of demand-controlled heat recovery ventilation systems with central and zonal control in a single-family house
No full textImproving ventilation efficiency in residential buildings is crucial to reducing energy consumption while maintaining indoor air quality. This study investigates three demand-controlled ventilation (DCV) strategies compared to a traditional constant airflow (CAV) system in a single-family house. The DCV strategies evaluated include central CO₂ control using a sensor in the exhaust duct, central CO₂ control using the highest reading from individual rooms, zonal CO₂ control with two zones prioritized by the highest CO₂ level in each, and constant airflow as the baseline system. Dynamic energy simulations were performed using a calibrated model based on Estonian climate conditions and a typical residential occupancy profile. Each control strategy was simulated in combination with three types of heat recovery ventilation units: rotary heat exchanger (RHE), energy recovery ventilator (ERV), and heat recovery ventilator (HRV). Results show that energy saving of demand-controlled system with dual-zone control was 33% while maintaining indoor air quality, but central control with exhaust sensor resulted in negligible saving. Notably, the dual-zone strategy with enthalpy recovery plate achieved the lowest overall energy consumption, reducing both space heating and fan electricity demand. The findings highlight the importance of sensor placement, control logic, and heat recovery selection in optimizing ventilation energy performance in residential buildings
A study to design a novel device for improving knee range of motion and reducing hamstring muscle tightness
No full textBackground-Restoration of knee joint mobility and stretching of surrounding muscles are critical aspects in both post-operative and athletic conditions. The functional impairments could be due to joint stiffness or because of hamstring muscle tightness. The conventional rehabilitation protocols for limited mobility of the knee often include a range of motion (ROM) manual exercises by the therapist may result in time-consuming, reduced patient-control, and a documentation of treatment progress report may be challenging. Considering this proposed machine facilitates controlled, small incremental movement and integrates ROM and hamstring muscle stretching at once. Methods-The proposed novel design has features for individual care and records progress data of activity performed on the equipment, including the maximum achieved angle of knee movement. The current design will prioritize the precise 0.3° step incremental movement with combined action required for improving joint stiffness and reducing hamstring muscle tightness with the use of a linear actuator, thus preventing microtrauma from occurring to patients. Result-This novel device will offer a precise, controlled, patient-centered approach in addressing two important clinical problems in a single setting without causing extra cost for the treatment. Discussion-The study is on precise design and automated feedback system facilitate effective home-based physiotherapy and rehabilitation applications
Challenges in Alzheimer’s Drug Development: Failures, Therapeutic Barriers and Clinical Translation
No full textAlzheimer's disease (AD) continues to pose a significant challenge in pharmaceutical research, with drug development marked by high attrition rates despite decades of investigation. Numerous therapeutic candidates, particularly those targeting amyloid-beta and tau proteins, have shown promise in preclinical studies but failed to produce substantial clinical benefits. Most failures occur in late-stage trials, especially Phase II and III, due to limited therapeutic efficacy, unforeseen adverse effects, or inability to alter disease progression. The complex and multifactorial nature of AD pathology including neuroinflammation, synaptic degeneration, and metabolic disturbances makes developing a single curative treatment highly difficult. This review examines the underlying reasons for these setbacks, focusing on clinical trial outcomes and the limitations of previous pharmacological approaches. Examples of unsuccessful candidates underscore persistent gaps in understanding disease mechanisms and therapeutic targeting. Addressing these challenges requires a paradigm shift toward early diagnosis, patient-specific precision medicine, and combination therapy strategies. Additionally, advancing biomarker discovery, employing adaptive and innovative trial designs, and exploring novel molecular targets may improve the likelihood of clinical success. By integrating these approaches, future research holds the potential to overcome existing barriers and deliver effective interventions for AD
Biochar based Nanocomposite derived from Watermelon Rinds as a Novel Adsorbent for Removal of Acid Red 27 Dye: Reusability and Phytotoxicity Assessment
No full textWater pollution emerges as a pressing global problem due to rise in population, urbanization, industrialization, and agricultural intensification. Dye contamination in water resources is a serious threat for environment and public health, thus effective strategies are needed to solve the problem. The watermelon fruit rind wastes were used as a raw material for synthesis of biochar nanocomposite for Acid red 27 (AR27) dye removal from aqueous solution. Adsorption has gained attention as a promising technique for AR27 dye removal due to its simplicity, flexibility, cost-effectiveness, and ease of operation etc. The batch study was executed to analyze performance of synthesized watermelon fruit rind biochar (WMR) and MnO2/WMR biochar nanocomposite as sorbent for AR27 dye elimination from aqueous medium. Experimental findings reported that MnO2/WMR biochar nanocomposite increased AR27 dye elimination in comparison to WMR biochar. AR27 dye removal (80 mg L-1) was recorded 85% at pH 5 by 0.3 g MnO2/WMR biochar nanocomposite. Reusability test reported that WMR biochar and MnO2/WMR biochar nanocomposite can be used up to five consecutive cycles. Thus, application of MnO2/WMR biochar nanocomposite is a renewable resource with high AR27 dye adsorption efficiency, thus can be applied for dye polluted wastewater treatment and environment protection
Impact of Waste Management on Public Health and Environmental Sustainability
No full textRapidly escalating global waste generation poses serious challenges to environmental quality and public health. Currently, as per the World Bank's What a Waste 2.0 report, the world produces over 2 billion tonnes of solid waste annually, a figure projected to rise to 3.4 billion tonnes by 2050. This review provides a critical analysis of major waste streams - municipal, industrial, biomedical, electronic, and radioactive - and evaluates common waste management practices alongside their environmental and health impacts. Improper waste handling is found to contaminate air, water, and soil, contributing to climate change and biodiversity loss. Unmanaged landfills emit methane, while open burning and incineration release toxins like dioxins and heavy metals, which have been linked to cancers and other diseases. Exposure to waste pollution elevates risks of respiratory illness, infections, and vector-borne diseases in nearby communities. A comparative analysis of case studies highlights how high-income countries have achieved minimal landfill usage (<1%) through recycling and waste-to-energy (WtE), whereas developing countries often rely on open dumps and informal recycling. Sustainable solutions - including policy reforms, technological innovations, and community engagement - are critically examined for their effectiveness. Remaining challenges, such as data gaps, weak enforcement, and infrastructure deficits, are discussed to outline future research and policy needs. The findings underscore an urgent need for integrated and sustainable waste management strategies worldwide to safeguard public health and ecosystems
Development and Optimization of Herbal Cream for Ringworm: A Natural Approach to Antifungal Treatment
No full textThe present study focuses on the formulation and evaluation of a herbal cream intended for the treatment of ringworm, a common fungal infection. With growing global interest in plant-based remedies, particularly those with antimicrobial properties, this research utilizes natural ingredients known for their antifungal efficacy. The cream was developed using ethanolic extracts of Aloe vera gel, Azadirachta indica (Neem), and Butea monosperma (Palash) prepared via maceration. The cream base comprised beeswax, liquid paraffin, borax, methylparaben, rose oil, and distilled water, and the formulation was completed using the slab method to ensure homogeneity. Five trial batches (F1H to F5H) were prepared and evaluated for physical appearance, pH, viscosity, phase separation, and skin irritancy. All formulations exhibited favorable visual properties, appropriate pH and viscosity, stability at room temperature, and no signs of skin irritation or erythema during application. Antifungal screening against Trichophyton, Microsporum, and Epidermophyton revealed that the herbal ingredients demonstrated notable antifungal activity. The overall results confirmed that all five formulations were physically stable, non-irritant, and suitable for topical application, highlighting the potential of herbal-based creams as effective, safe, and natural alternatives for managing fungal skin infections