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Hygrothermal performance analysis at the wall scale based on various hysteresis models
No full textThe hygrothermal performance of building components (e.g., exterior walls) influences indoor thermal and humidity conditions as well as the energy consumption of associated heating, ventilating and air conditioning (HVAC) systems. To assess such performance under dynamic and constant indoor conditions, a coupled heat and moisture transfer model was built with incorporating four hysteresis models based on Modelica platform. A typical wall system was selected to analyse hygrothermal performance during a typical meteorological year in Shanghai. Results show hysteresis effects significantly influence hygrothermal responses under dynamic conditions, with 20–30% higher moisture peaks, 8–12% higher cooling loads, and 15–20% higher moisture flux compared to non-hysteresis models, while impacts are minimal under constant conditions. The Frandsen model performs well in simulating adsorption-desorption cycles
Location Analysis of Upper-room UVGI on Germicidal Effect in Thermal Plume Dominant Room
No full textA numerical simulation was conducted to evaluate the germicidal effectiveness of an upper-room ultraviolet germicidal irradiation (UVGI) device in a room dominated by thermal plumes. A cylindrical model representing a seated human was used to generate free convection flow. The impact of the relative positions of the dummy and the UVGI device on the germicidal effect was analyzed. To simulate respiratory droplets emitted from the mouth, passive scalar transport was computed. The results indicated that the highest germicidal effect occurred when the dummy was located closest to the direction of UVGI irradiation, with a lateral offset of 0.8 meters. This suggests that germicidal performance is influenced not only by the UV irradiance distribution but also by airflow velocity and exposure time. In particular, when fast-moving air passes through the irradiation zone, effective disinfection may not be realized. Therefore, it is effective to position the irradiation zone further above the main airflow, where the air decelerates after impinging on the ceiling. These findings highlight the importance of strategic placement of UVGI devices to enhance their effectiveness in spaces where thermal plumes dominate air movement
Development and Open-Source Implementation of JOS-3: A Human Thermoregulation Model for Diverse Environmental Applications
No full textAccurate evaluation of human thermal comfort is essential for designing thermally acceptable environments. While widely used indices such as Predicted Mean Vote (PMV) and Standard New Effective Temperature (SET*) perform well under uniform and steady-state conditions, their applicability is limited in non-uniform or transient environments. In response, we developed a new open-source human thermoregulation model, JOS-3, to predict physiological responses more accurately under diverse environmental conditions. These include the representation of brown adipose tissue (BAT) activity under cold acclimation, aging effects, and solar heat gain at the skin surface due to shortwave radiation. In addition, we revised the algorithms for shivering thermogenesis, sweat distribution, and basal metabolic rate estimation. The model consists of 83 thermal nodes and employs the backward difference method for solving body temperature and physiological responses over time. JOS-3 was implemented in Python 3 and is publicly available under GitHub (https://github.com/TanabeLab/JOS-3), facilitating collaboration and use across research institutions. The present study aims to further enhance JOS-3 by addressing feedback from international projects and domestic users, such as emergency medical professionals requiring deep body temperature predictions. By expanding its applicability and accuracy, JOS-3 contributes not only to building environmental research but also to interdisciplinary fields involving human thermal physiology
Ventilation Performance of Ceiling-Supplied Displacement Ventilation in Medium-Sized Office Room tested by Full-Scale Model Experiment. Part 1 Effect of Supply Air Conditions and Number of Occupants on Temperature and Human-Originated Contaminant Concentration Distributions
No full textAfter the disaster of COVID-19, the displacement ventilation is in the spotlight, because of the high ventilation efficiency for the human-originated contaminant including droplet nuclei. However, the large diffusers for displacement ventilation tend to be avoided due to the high cost including installation and large floor area. On the other hand, the ceiling-supplied ventilation has many merits. In this paper, the ventilation efficiency of the ceiling-supplied displacement ventilation using developed supply diffuser units was examined by the full-scaled model experiment for medium-sized offices. The temperature and CO2 concentration emitted from person simulators as a tracer gas were measured, and the effects of air supply conditions and the number of occupants on the temperature and CO2 distribution were investigated. As a results, it was turned out that this ceiling-supplied displacement ventilation system has high ventilation efficiency and the normalized concentration of 0.5 can be obtained. Additionally, it is proved that the supply air velocity is an important parameter to determine the ventilation efficiency, and even if the occupant number is rather small, the ventilation efficiency is kept sufficiently good. Overall, it can be said that the ventilation efficiency of ceiling-supplied displacement ventilation is high and practical even in medium- sized office rooms
A data mining approach to evaluating the impact of occupancy levels on energy performance: A case study of a university educational building
No full textEducational buildings, including Classrooms, Study Halls, Research Laboratories, and departmental administrative offices are substantial contributors to energy consumption due to intensive utilization throughout the academic year. However, a considerable portion of this energy is wasted, primarily attributes to the inadequate awareness among occupants regarding energy-saving practices and the uninterrupted operation of building energy systems, irrespective of actual occupancy levels or demand patterns. This paper investigated the impact of occupant density on energy consumption for air conditioning, with a focus on gas consumption by a gas heat pump (GHP) system in an educational facility. The daily gas consumption per occupant-hour was calculated for the analysed space throughout the academic year. Hourly occupancy data was primarily gathered through field surveys, corresponding to specific space usage patterns to ensure accuracy. A hybrid model combining Gaussian Mixture Model (GMM)-based clustering with Bayesian Hidden Markov Models (HMMs) was developed to estimate hourly occupant numbers, grounded in real-time electricity consumption as a key variable. As a result, the analysis of air conditioning-related energy consumption indicated that optimizing load scheduling during low-occupancy periods could contribute to reducing the overall energy consumption of the educational building
Checkpoint inhibitors in cancer Immunotherapy: Mechanisms, Resistance, and Combination Strategies
No full textThe advent of immune checkpoint inhibitors (ICIs) represents one of the most significant paradigm shifts in modern oncology, moving the therapeutic focus from the tumor cell to the host's immune system. By targeting critical negative regulatory pathways, primarily the Cytotoxic T-Lymphocyte-Associated protein 4 (CTLA-4) and Programmed cell Death protein 1 (PD-1)/PD-L1 axes, these therapies have fundamentally altered the treatment landscape for a growing list of malignancies. This review provides a detailed exposition of the discrete molecular and cellular mechanisms underpinning CTLA-4 and PD-1 blockade, highlighting their distinct roles in the cancer-immunity cycle. We then delve deeply into the multifaceted and evolving landscape of therapeutic resistance, dissecting the tumor-intrinsic and extrinsic factors that lead to primary (de novo) or acquired (adaptive) non-response. Finally, we systematically analyze the scientific rationale and clinical evidence for current and emerging combination strategies. These approaches, including pairings with chemotherapy, radiotherapy, targeted agents, anti-angiogenics, and other immunotherapies, are being rationally designed to overcome specific resistance mechanisms, amplify therapeutic efficacy, and ultimately broaden the patient population who may achieve durable benefit from immunotherapy
Production Design of Sucrose Ester Using Purification Process
No full textSucrose ester (SE) is an anionic surfactant compound with a high affinity for water and potential applications as a component in personal care products. This study aimed to determine the SE purification process using the liquid-liquid extraction method with different types of salts, specifically sodium chloride (NaCl) and potassium chloride (KCl), alongside SE (Palmitate, Laurate, and Stearate). The production process of SE employs a sucrose to fatty acid ratio of 1:3, with the addition of a 6% w/v potassium carbonate (K2CO3) catalyst. The temperature is initially set at 60 °C for 30 minutes and is gradually increased to 100 °C for 90 minutes. The SE purification process is conducted using liquid-liquid extraction. Lactic acid is added until the pH reaches 5. The organic solvent isobutanol is combined with saltwater (10% salt in a 1:10 ratio). The temperature is maintained within the range of 55-70 °C. The organic phase is mixed with saltwater in a 1:1 ratio. The final product is then evaporated. HPLC analysis revealed only monoester compounds. FTIR analysis of sucrose ester indicated the presence of C-H and C=O functional groups within the wavelength range of 1730.15 - 1732.08 and 2850.79 - 2854.65. After purification, emulsion stability, foam stability, and yield parameters decreased. However, droplet size, surface tension, and interfacial tension parameters increased. The use of KCl salt proved to be the most effective treatment. Instead of being the primary emulsifier in the formulation of personal care products, the sucrose ester purification product is more suited as a solubilizer
Estimated CO
No full textThe primary energy supply in Indonesia is still dominated by fossil fuels, leading to a significant increase in CO2-eq emissions, particularly from the transportation and industrial sectors. The Indonesian government has implemented the B40 program (a blend of 40% biodiesel and 60% petroleum diesel) to mitigate CO2-eq emissions. This research aims to calculate the total CO2-eq emissions throughout the entire life cycle of B100 production based on the principles of Life Cycle Assessment (LCA) as specified in SNI ISO 14040:2016 and SNI ISO 14044:2017. The analysis compares the CO2-eq emissions of conventional diesel (B0) and B100. The results indicate that B100 has the potential to reduce particulate emissions by 40-60%, carbon monoxide (CO) by 10-50%, and hydrocarbons (HC) by 10-50% compared to B0. The CO2-eq emission factor for B0 was found to be 4,354.81 kg CO2-eq/kL, and for B100 it was 2,155.64 kg CO2-eq/kL. This demonstrates a significant reduction in emissions with the use of B100, resulting in a decrease of 2,199.17 kg CO2-eq/kL or 50.50% from B0. However, the study also highlights the environmental challenges associated with the expansion of oil palm plantations, including deforestation and land degradation, which contribute to CO2 emissions
Formula of Pelletized Slow-Released Fertilizer Based on Pineapple Plant Stump Biomass Compost–Coal Fly Ash and its Recycling Application on Ananas Plantation
No full textThis study evaluates the performance of pelletized slow-release fertilizers (SRFs) formulated from pineapple plant stump biomass compost and coal fly ash at varying ratios, with the dual aim of enhancing soil nitrogen availability and promoting vegetative growth in pineapple, while valorising agricultural residue. A field trial was conducted from 2021-2022 in Lampung, Indonesia. Mineral fertilizers were encapsulated in emulsified polymer coatings at lower and higher coating concentrations. Pelletized SRF treatments were arranged in a randomized complete block design for control and various compositions of compost + fly ash. Soil N status was monitored periodically via total N, nitrate (NO₃⁻), and ammonium (NH₄⁺) assays, alongside measurements of N losses through leaching and volatilization. Vegetative responses were quantified by leaf count, leaf area index, and root biomass at 30 days after transplanting. All SRF treatments improved soil N availability relative to the control, with the 40% compost formulations, especially at high coating concentrations, exhibiting the best soil N status. These high-compost SRFs also delivered potential gains in root biomass and foliar development, which can be attributed to the enhanced soil organic matter. The results demonstrate that pineapple stump–fly ash SRFs can simultaneously recycle biomass waste and sustainably boost nutrient efficiency and plant growth in pineapple cultivation
Integrating Halal Principles in the Palm Oil Biomass Sector to Enhance Sustainable Energy Security
No full textDeveloping a halal ecosystem within the palm oil biomass sector represents a significant opportunity for utilizing primary renewable feedstock in Indonesia and Malaysia. It is also a strategic initiative to enhance sustainable energy security while meeting the growing international demand for clean and Sharia-compliant energy solutions. This paper examines how integrating halal principles (purity, stewardship/khalīfah, anti-waste/isrāf, and social justice) into palm biomass value chains can strengthen social legitimacy, support sustainable bioenergy deployment, and contribute to national energy security. This research uses a qualitative descriptive design, incorporating literature reviews of halal-related regulations and certification standards related to biomass. Findings suggest that the application of halal standards, from the processing of by-products such as empty fruit bunches, fibers, trunks, and shells to the distribution of bioenergy, can improve transparency, operational efficiency, and global competitiveness, particularly as the worldwide energy market increasingly emphasizes sustainability and ethical sourcing. Additionally, obtaining halal certification for biomass-based energy products opens new export opportunities, particularly in the Middle Eastern and South Asian markets, where halal compliance is a key requirement. Establishing a halal-based framework in the palm oil biomass industry can be a foundational component in achieving a more inclusive and sustainable national energy transition