Comfort Performance Research Articles

Field test of machine-learning based mean radiant temperature estimation methods for thermal comfort-integrated air-conditioning control improvement and energy savings

Advanced control strategies for heating, ventilation, and air-conditioning (HVAC) systems aim to enhance both buildings' energy efficiency and occupant thermal comfort. Despite their potential, real-world demonstration studies on such advanced technologies are still lacking. This study presents a field demonstration of a real-time predicted mean vote (PMV)-based HVAC control strategy in a typical residential building under hot and dry climate conditions. This study introduces an advanced thermal comfort-based controller (TCC) for the PMV-based HVAC control. TCC continually assesses indoor and outdoor thermal conditions and adjusts the HVAC setpoint temperature to optimize real-time energy use while ensuring satisfactory indoor thermal comfort. Machine learning models for the PMV-based HVAC control system are employed to estimate a mean radiant temperature (MRT) point, which is one of the variables used to calculate real-time PMV values. Three machine learning models (i.e., linear regression, regression trees, and artificial neural network) are adopted in this study with non-stationary real-time input values, including times, pre-determined setpoints, and indoor and outdoor temperatures. The developed TCC is installed in a full-scale experimental house in Kuwait, which is under hot and dry climate conditions, to assess the house's indoor thermal comfort and AC energy efficiency performance. Results indicate that the TCC provides better thermal comfort performance compared to the non-TCC case, including up to a 60% improvement in PMV. The proposed TCC controlled by the machine learning methods demonstrates HVAC energy savings potential of over 20% while meeting the desired thermal comfort levels in the experimental building. These findings are expected to be valuable, as they can contribute to reducing cooling energy in residential buildings in hot and dry climate conditions.

A novel perineal exposure method in laparoscopic abdominal perineal resection of rectal cancer: a case series study

BackgroundAbdominal perineal resection (APR) of rectal cancer, also known as Mile’s procedure, is a classic procedure for the treatment of rectal cancer. Through the improvement of surgical skills and neoadjuvant therapy, the sphincter-preserving rate in rectal cancer patients has improved, even in patients with ultralow rectal cancer who underwent APR in the past. However, APR cannot be completely replaced by low anterior resection (LAR) in reality. APR still has its indications, when the tumor affects the external sphincter, etc. Good perineal exposure in APR is difficult and can seriously affect surgical safety and the long-term prognosis.MethodsWe reviewed the records of 16 consecutive patients with rectal cancer who underwent APR at Anqing Municipal Hospital from January 2022 to April 2023, including 11 males and 5 females, with an average age of 64.8 ± 10.3 years. The perineal operation was completed with the Lone-Star® retractor-assisted (LSRA) exposure method. After incising the skin and subcutaneous tissue, a Lone-Star® retractor was placed, and the incision was retracted in surrounding directions with 8 small retractors, which facilitated the freeing of deep tissues. We dynamically adjusted the retractor according to the plane to fully expose the surgical field.ResultsAll 16 patients underwent laparoscopic-assisted APR successfully. Thirteen procedures were performed independently by a single person, and the others were completed by two persons due to intraoperative arterial hemostasis. All specimens were free of perforation and had a negative circumferential resection margin (CRM). Postoperative complications occurred in 4 patients, including urinary retention in 1 patient, pulmonary infection in 1 patient, intestinal adhesion in 1 patient and peristomal dermatitis in 1 patient, and were graded as ClavienDindo grade 3 or lower and cured. No distant metastasis or local recurrence was found for any of the patients in the postoperative follow-up.ConclusionsThe application of the LSRA exposure method might be helpful for perineal exposure during APR for rectal cancer, which could improve intraoperative safety and surgical efficiency, achieve one-person operation, and increase the comfort of operators.

Enhancing Visual Comfort and Energy Efficiency in Office Lighting Using Parametric-Generative Design Approach for Interactive Kinetic Louvers

The number of desk workers who frequently conduct their jobs at home has increased dramatically during Covid-19. Work-from-home flexibility makes it attractive for workers and companies, resulting in a “Work-Style Reform” after the Covid-19 pandemic. However, the quick conversion of home spaces into workplaces cannot always sufficiently respond to users’ visual comfort and daylight performance needs which are primary contributors to occupant well-being and productivity. Therefore, this study adopts a mixed-methodology method that integrates parametric thinking, biomimetic, conceptual design, kinetic strategy and the DIVA approach to develop a real-time parametric-generative circular design for multi-objective adaptability that optimizes visual comfort and electric lighting energy efficiency for multiple occupants simultaneously. Parametric simulations of 1458 different options (five different runs per case: a total of 7290) were conducted to assess how the louvers perform regarding daylight, glare, and electric energy usage. Implementing an interactive kinetic louver greatly improved daylight performance in all orientations while simultaneously avoiding visual discomfort for multiple occupants. Furthermore, the use of this façade modification resulted in a substantial decrease in electrical lighting energy consumption, reducing the values from 14.22 to 0.2 kWh/m2/year, 8.1 to 0.18 kWh/m2/year, and 12.88 to 0.18 kWh/m2/year for South, East, and West orientations, respectively. Integrating users' lighting level preferences and the dynamic transitory sensitive area on the façade considerably reduces electric lighting consumption by around 99% compared to the ASHRAE 90.1 standard's lighting profile.

DFA Analysis Revolutionizes FSAE Steering, Enhancing Efficiency in Automotive Design

In the dynamic realm of automotive engineering, particularly in Formula Society of Automotive Engineers (FSAE) racing, where vehicle assessment is based on efficiency, motor power, chassis dynamics, and steering, there exists a notable focus on steering system design. This research delves into the conceptualization and component development aimed at aiding automotive mechanics in crafting steering systems for FSAE race cars. Employing Solid Edge 2021 software, the study utilizes the Design of Assembly (DFA) analysis method to streamline the mechanical process. Through DFA analysis, the study assesses various Technical Attributes (TAs) of the steering system, revealing values ranging from 0.548 to 1.765. The ideal steering system ensures that the desired steering input by the driver aligns with the output motion of the vehicle, known as the Ackerman condition. Steering gear mechanisms translate rotational motion into translation and adjust the effort applied to the steering linkage. The study's findings contribute to the advancement of steering system design in FSAE vehicles, emphasizing ergonomic considerations and the utilization of advanced software tools like Catia and Solid Edge 2021 for enhanced performance and safety. Highlight: FSAE steering: DFA analysis enhances design efficiency for racing vehicles. Software aid: Solid Edge 2021 streamlines FSAE steering system development. Ergonomic focus: Design prioritizes driver comfort and vehicle performance optimization. Keywoard: FSAE vehicles, Steering system design, DFA analysis, Solid Edge 2021, Ergonomics

Multi-fanning and its improvement of thermal and wind comfort: An auxiliary means to air conditioning

Space cooling has led to an increase in building energy consumption and the incidence of issues related to indoor air quality. Faced with these challenges, the use of dynamic airflow has become a major area of interest in order to create a comfortable, healthy, and sustainable environment. However, it is revealed that previous studies mostly used single air sources to supply airflow uni-directionally, studying their thermal comfort performance mainly at background temperatures below 30 °C. Considering the dynamic velocity and direction characteristics of outdoor natural wind, in this study, we designed twelve wind conditions and analyzed their airflow characteristics and comfort evaluation. The analysis results revealed that multi-fanning airflows had more dynamic velocity and direction characteristics than directly-supplied constant mechanical wind. Besides, twenty subjects participated in this experiment, they were exposed to these twelve wind conditions at two background temperatures of 31 °C and 32 °C. The findings indicated that, other than the air velocity, the diversity of incoming airflows’ direction was also of utmost importance in affecting wind comfort. According to the thermal and wind comfort evaluations, it was found that a diversified use of electrical fans can still maintain great wind comfort without sacrificing thermal comfort in hot environments (up to 32 °C). This study recommended the multi-fanning cooling scenario as an auxiliary means to air conditioning. It might not only help mitigate anthropogenic emissions to achieve carbon neutrality but also be greatly beneficial to the comfort, health, and well-being of occupants.

Contribution of advanced windows and façades to buildings decarbonization: A comprehensive review

On a global level the building sector consumes about 45.00% of energy consumption, contributes about 40.00% to emission, uses 30.00% of water and impacts the environment by generating 30.00% of waste. Although windows are important components of a building that provide natural lighting and ventilation and establish necessary contact with the external environment necessary for healthy indoor ambient, they permit entry of undesirable solar heat in summer and allow escaping heat from the indoor ambient in cold seasons, which aggravate the building needs for energy and increase its contribution to atmospheric emissions. The present investigation provides a review on research, development, and applications of advanced windows in the building sector. The introduction highlights the importance and contribution of advanced glazing technology to improving energy, comfort, and thermal performance of buildings. The review includes natural illumination and ventilation, thermal comfort and discusses the effects of window to wall ratio on natural illumination and ventilation of windows and façades. The review also covers recent developments in glazed windows and façades including performance enhancements by using reflective solar films, vacuum glazing, windows with filling materials, windows with water flow, window with phase change material, window with stagnant inert gas filling, ventilated windows and façades and windows with aerogel. A special section was also included on smart glazing for windows and façades showing the new tendencies and applications in the building industry. Since commercial programs and open access codes are handy tools for simulation and performance calculations a section is dedicated to these codes. The conclusion section contains the most relevant conclusion of the review as well as future trends in research and developments in the area. The topics included in this review can be helpful for experienced and young researchers, practicing engineers and general readers interested in windows and façades.

Thermal performance of a novel traditional Chinese personal heating device (Huotong) combined with PCMs

Chinese traditional individual heating equipment with a history of hundreds of years “Huotong” was widely used in rural areas. The Huotong consisted of a closed wooden barrel-shaped outer wall and an iron basin with combustion layer. However, the traditional Huotong had problems of low energy utilization efficiency and poor thermal comfort. Thus, a novel Huotong combined with phase change materials (PCMs) was proposed. The basic model of novel Huotong was designed and manufactured. The thermal performances of the novel Huotong under two kinds of heat sources of charcoal heating and electric heating were investigated. The results showed that: (1) Under the method of charcoal heating, the heat storage and thermal comfort performance of the novel Huotong were higher than that of the traditional Huotong. Under the three-charcoal mass of 0.15, 0.25 and 0.5 kg, the heat storage performance of the novel Huotong was 1.36, 1.43 and 1.52 times of the traditional Huotong, respectively. The average PMV values of the novel Huotong was 0.92, 1.17 and 1.31, while for the traditional Huotong was 0.87, 1.32 and 1.58, respectively. (2) Under the four electric heating methods, the thermal efficiency of the novel Huotong was 1.63, 1.61, 1.47 and 1.39 times of the traditional Huotong, respectively. The heat storage performance was 1.72, 1.67, 1.47 and 1.28 times than that of the traditional Huotong. The average PMV values of the novel Huotong was 1.25, 1.22, 0.69 and 1.68, while for the traditional Huotong was 1.64, 1.53, 0.87 and 2.03, respectively.

Thermal response and performance evaluation of floor radiant heating system based on fuzzy logic control

The floor radiant heating system is widely used in various buildings due to its advantages such as high efficiency, comfort, and uniform heating. Generally, research on floor radiant heating systems focuses on energy saving, but the issue of slow thermal response during the heating process has not been solved. To solve the problem of slow thermal response and uneven indoor thermal environment in floor radiant heating systems, a fuzzy logic control theory based on optimal fuzzy rules was proposed. The floor radiant heating system based on fuzzy logic control was established by the TRNSYS-MATLAB integrated control platform. The study compared the thermal response and thermal comfort performance of PID control, fuzzy logic control, and optimized fuzzy control methods. The results showed that fuzzy logic control performed better than PID control in controlling the system's thermal performance and indoor thermal environment. Compared to PID control, the optimized fuzzy control reduced the thermal response time by 64.60%, and the total energy consumption of the water pump and heat pump decreased by 222 kWh and 329 kWh, respectively. The proposed fuzzy logic control demonstrates favorable thermal response characteristics and holds substantial potential for energy conservation within the increasingly prevalent floor radiant heating systems.

Cold Habituation Does Not Alter Thermal Responses or Manual Dexterity During Prolonged Cold Air Exposure

Background: Habituation is a pattern of cold acclimatization characterized by attenuated cold defense responses, including a reduction in peripheral vasoconstriction and subsequent increase in skin temperature (TSk) as well as a decrease in shivering thermogenesis. Habituation is achieved through repeated reductions in TSk, rather than deep body core temperature (TC), via exposure to prolonged cold air or brief cold-water immersion. Due to improvements in TSk, enhanced manual dexterity and peripheral cold injury risk reduction are purported benefits of cold habituation. Warfighters frequently operate in cold climates and experience decrements in manual dexterity and strength. These functional losses can negatively impact mission critical tasks and training exercises; however, the effectiveness of cold habituation as a potential countermeasure to alleviate the deleterious effects of prolonged cold exposure on peripheral temperatures, thermal comfort, and hand function is unclear. Purpose: To evaluate the influence of eight consecutive cold air exposures on the thermal (TC and TSk), perceptual (thermal comfort and sensation), and functional (manual dexterity and strength) responses to cold air. We hypothesized that TSk would be higher and perceptual responses and manual dexterity improved, following repeated cold exposure. Methods: Eight young adults (6 M/1 F/1 FTM; 21 ± 2 years; %BF 24.5 ± 7.0) underwent a 2-h cold air exposure (8 °C, ~50% RH) on 8 consecutive days wearing minimal clothing. On Day 0 (baseline exposure ~1 week prior) and Days 1 and 8 of repeated exposure, TC was recorded continuously via a telemetry pill used as a rectal suppository. Extremity (Thand and Tfinger) and mean weighted TSk (MWTSk) from 8 skin sites were recorded continuously. Thermal comfort (TC) and thermal sensation (TS) were recorded at 20 min intervals. Expired gases were collected at 20 min intervals and used to calculate metabolic heat production (MHP). Manual dexterity was assessed using the Purdue Pegboard and Minnesota Manual Dexterity Test (MMDT), and hand strength were measured before and at the end of cold exposure. Results: TC changed across time ( p < 0.05) but did not differ between days ( p > 0.05). MWTSk, Thand, and Tfinger decreased across time ( p < 0.05) but also did not differ between days ( p > 0.05). Mean and minimum whole-body TS and TC were not different between days ( p > 0.05). MHP increased across time ( p < 0.05) but did not differ between days ( p > 0.05). Purdue Pegboard, MMDT task performance, and hand strength did not differ between days ( p > 0.05). Conclusion: Eight consecutive days of cold air exposure does not augment extremity skin temperature, thermal comfort, or manual performance during prolonged cold conditions. Supported by U.S. Army Medical Research and Development Command, Military Operational Medicine Research Program; author views not offcial US Army or DoD policy. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Students’ thermal comfort and cognitive performance in fan-assisted naturally ventilated classrooms in tropical Singapore

Fan-assisted cooling strategies are widely employed in tropical climates due to their energy-saving benefits while ensuring thermal comfort through increased air temperature and air velocity. This study conducted experiments involving secondary school students in fan-assisted naturally ventilated classrooms in tropical Singapore. A total of thirty-six students from two secondary schools participated in this study. The classroom thermal environment was measured, students' thermal comfort was surveyed, physiological responses were monitored, and students' cognitive performance was assessed in different classrooms with various fan configurations. Thermal comfort survey results indicated that students' thermal comfort can be maintained at neutral with elevated air velocity, when classroom temperature remained at or below 30 °C. Students’ wrist skin temperature, arm skin temperature, and heart rate showed significant differences under various thermal conditions and thermal sensations, suggesting the potential use of physiological parameters to predict students' thermal comfort in fan-assisted naturally ventilated classrooms. This study also observed a significant impact of classroom thermal condition on students' cognitive performance. It was found in both schools that students' cognitive performance scores decreased significantly with increased temperature and decreased air velocity. Additionally, students' cognitive performance decreased by 9.2 % and 18.1 % in slightly warm and warm sensations, respectively, compared to the neutral sensation. These findings underscore the significance of air velocity as a crucial factor in the design of classroom environments, particularly in tropical climates, to enhance students' thermal comfort and optimize their cognitive performance.

Thermal comfort, daylight, and energy performance of envelope-integrated algae-based bioshading and static shading systems through multi-objective optimization

Energy-efficient envelopes integrated with different shading devices, as noticeable passive design strategies, have been of great interest for research studies. However, there is a lack of attention on optimizing envelope-integrated novel algae-based bioshading systems (ABBS) in comparison with other shading devices to enhance buildings’ sustainability-oriented performances. Integrating microalgae culture system with building façade as a state-of-the-art bioshading system is among recent developments in high-performance architecture. Although, challenges/limitations concerning different performances of this technology have not been extensively addressed. The present study conducts a multi-objective optimization framework to investigate the Thermal Comfort Percentage (TCP), Useful Daylight Illuminance (UDI), and Energy Usage Intensity (EUI) in a school building to evaluate the relationship between the performance objectives and design variables (shading characteristics, window-to-wall ratio (WWR)) through comparing different static shading systems and ABBS in the hot (BSh) and cold semi-arid (BSk) climates. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method was also applied to determine the best design options within Pareto frontiers. Results demonstrated that horizontal louver by 128.52 % TCP, 15.10 % UDI improvement in south-oriented façade in BSk, and overhang with fin (OF) by 18.99 % EUI reduction in southern facade in BSh climates contribute the most to enhance the objective metrics. Also, ABBS was not a stand-first system to enhance all the objective metrics compared to the other shading systems in none of the examined climates. Sensitivity analysis indicated that WWR has the most significant positive impact on EUI compared to the other studied metrics in almost all design options.

The Thermal Comfort and Hygrothermal Performance of the First Certified Passive House in Estonia

The Thermal Comfort and Hygrothermal Performance of the First Certified Passive House in Estonia

Precision Agriculture: Assessment of Ergonomic Risks of Assisted Driving System

Background: the precision agriculture field optimizes resource use, enhancing performance. However, this leads to exposure to ergonomic risks for operators, in particular, tractor drivers, potentially causing musculoskeletal disorders (MSDs). This study investigates how the display position in a semi-automatic tractor system influences operator comfort and muscle activation during harrowing operations. Methods: the assessment of muscular strain involved the use of surface electromyographic devices, while posture was evaluated throughout the analysis of the distribution of pressure exerted by the operator’s body on the seat, which was observed using two barometric pads, each positioned on the backrest and base of the seat. Finally, infrared thermography (IRT), a non-invasive tool to assess muscle activation, was used to measure the surface temperature of the driver’s back. The results showed a significantly greater muscular activation display for the position of display in semi-automatic driving at 50° and 80°. Conclusions: this study showed how the position of the display on the vehicle negatively influences posture, exposing workers to the risk of developing fatigue and, therefore, discomfort, with the potential onset of MSDs. The combined use of sEMG and IRT allowed for a non-invasive, cheap, and repeatable mechanical and functionality analysis.

Achieving heat storage coatings from ethylene vinyl acetate copolymers and phase change nano-capsules with excellent flame-retardant and thermal comfort performances

The heat-storage coatings from ethylene vinyl acetate (EVA) copolymers were developed by incorporating in-situ synthesized phase change nano-capsules (NEPCMs). The coatings were applied to the interior walls of the building, aimed at enhancing thermal storage and flame-retardant performances. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) are utilized to evaluate the chemical composition of the NEPCMs. At the same time, the thermal properties and microstructure of NEPCMs and the coatings are analyzed using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The enthalpy of NEPCMs is 158.14 J/g, while that of heat-storage coatings is 56.45 J/g. NEPCMs and heat-storage coatings exhibit excellent thermal storage performance even after 200 heating-cooling cycles, demonstrating the excellent thermal stability of NEPCMs and heat-storage coatings. Furthermore, excellent flame-retardant properties are also provided by the heat-storage coating. In dynamic heat transfer experiments, under the same conditions, the heat-storage coatings were capable of maintaining the chamber in the thermal comfort zone (24–28 °C) for 141 min, while the conventional coatings lasted only 34 min. The results show that incorporating heat-storage coatings can effectively enhance the thermal regulation performance of interior walls and improve the thermal comfort of indoor environments. Therefore, heat-storage coatings hold a high potential for application in energy-saving buildings.

Passive cooling and thermal comfort performance of Passive Downdraught Evaporative Cooling (PDEC) towers in a Saudi library: An on-site study

In the hot arid climate of Saudi Arabia, where air conditioning, primarily fueled by fossil fuels, accounts for a significant portion of energy consumption, the implementation of Passive Downdraught Evaporative Cooling (PDEC) towers presents a sustainable solution. This study conducts an extensive evaluation of PDEC towers in a public library, focusing on their effectiveness in reducing reliance on conventional cooling and enhancing thermal comfort. Through detailed field measurements, the study examines the influence of wind speed on the towers' cooling performance, correlating it with internal environmental conditions. The research extends to a comparative analysis of two prominent thermal comfort models: the Predicted Mean Vote (PMV) and the Adaptive Thermal Comfort (ATC) model. Findings indicate a notable interaction between wind speed and indoor air temperature, where increased wind speeds correspond to higher indoor temperatures. Despite this, the PDEC towers demonstrate a significant reduction in temperature, maintaining cooling effectiveness between 70 % and 75 %. The comparative study of thermal comfort models reveals that the ATC model provides a more relevant assessment of comfort levels in naturally ventilated spaces, with 71 % of the recorded temperatures falling within the comfortable range during the monitoring period. The research highlights the PDEC tower's potential in delivering effective passive cooling, adaptable to wind speed changes, and contributing to a sustainable and energy-efficient building environment in hot arid climates.

The relationship between thermal comfort, performance, and electroencephalogram during cognitive tests at normal indoor temperatures in summer

Electroencephalograms have been proposed as potential physiological indicators to gauge the thermal comfort and cognitive performance of individuals in indoor environments, yet further experimental validation is required. In this study, a simulated experiment was conducted in a climatic room during summer, with temperatures set at 24 °C, 26 °C, 28 °C, 30 °C, and 32 °C. Twenty participants, attired in typical summer clothing (short sleeves and long pants totaling 0.39 clo), undertook cognitive tests assessing short-term memory and concentration while seated, alongside providing thermal comfort ratings. Electroencephalogram signals were continuously recorded from 14 electrode channels across the brain during the second cognitive test unit, spanning the 70th to 90th minute of experimental exposure. The relative power of electroencephalogram signals was computed and analyzed in conjunction with thermal comfort voting, revealing a significant impact of indoor temperature variations on α-band activity in the occipital lobe, with peak α-band relative power observed at 26 °C. Moreover, the whole-brain α-band relative power was significantly higher in states of thermal comfort compared to discomfort, particularly concentrated in the occipital lobe. Linear correlation analysis between cognitive test results and electroencephalogram signals indicated significant associations between the relative power of whole-brain β, δ, and θ bands and scores from the concentration-focused Flanker test. Channels O1 and P8 emerged as potential candidates for single-channel electroencephalogram signals, offering insights into thermal comfort status and cognitive performance related to concentration.

Proposal and application of a raised multilayer flooring system and its influences on thermal environments

ABSTRACT This study discusses a raised multilayer floor (RMF) system. The RMF system is characterized by gaps between the slab and flooring material. It has been applied to a wide range of building types in Japan because it is known to excel in acoustic absorption. The thermal performance of the RMF systems was considered to be more efficient than that of a floating floor (FF) system in which a heating panel is attached to a floor slab. However, this has not been sufficiently explored. In this paper, 72-hour in-situ temperature measurement test was performed to compare the thermal performance of the RMF and FF systems. They were applied to two identical rooms in a reinforced concrete (RC) building. The tests were performed under three different heating conditions. There was no heating, air-conditioning heating, or floor heating (FH). The RMF system was found to be more effective than the FF system in terms of FH operation speed, comfort level, energy efficiency, and vertical temperature distribution. The RMF system increased the floor surface temperature about 2°C higher than the FF system. 72-hour FH operation at a 26°C setting resulted in the RMF system reducing energy consumption by approximately 10% than the FF system.

Pengaruh Jumlah Penumpang dan Durasi Buka Tutup Pintu Terhadap Perubahan Suhu (Studi Kasus: Kereta Inspeksi PPI Madiun)

The inspection train is specialized equipment used for examining railway tracks, transporting personnel, and carrying work equipment. The inspection train must be equipped with operational tools, monitoring equipment, and work comfort equipment. One of the comfort equipment is air circulation control, which should provide comfort to the personnel while working. Factors influencing the air temperature inside the inspection train include the number of passengers and duration of door opening. This research employs the Design of Experiment data processing method, with the data analyzed using a 2-factor factorial design experiment, with the assistance of Minitab software to understand the influence of the number of passengers and the duration of door opening-closing on temperature changes inside the inspection train. The result obtained from Minitab analysis indicate that the number of passengers has a significant influence on temperature changes inside the inspection train, accounting for 5.2% of the variation. On the other hand, the duration of door opening-closing does not have a significant effect on temperature changes. Additionally, the interaction between the number of passengers and the door open-close duration does not have a significant influence on temperature changes inside the PPI Madiun Inspection Train.

An innovative sanitary fixture for performing ablution in public facilities

PurposeThis study aims to introduce the design and the design process for an innovative sanitary fixture to be used in public facilities for the purpose of ablution. This purpose-made fixture is needed to support the hygienic, safe and comfortable performance of this essential function in public facilities in many parts of the world. The study also clarifies the need for this function and critically reviews current designs to address it.Design/methodology/approachThe study started by critically reviewing the standard built-in models for ablution. It also identified and analyzed new approaches to designing standalone ablution fixtures. The study then specified the characteristics of a better ablution fixture and involved drafting a design based on these characteristics, making a wooden prototype to test the design and receiving users’ feedback. The design was adjusted and tested again for more feedback. Finally, the study resulted in the development of a final design. It used digital fabrication to create the design prototype with improved aesthetics, tested it again and received user feedback.FindingsA survey of users showed that they found the innovative fixture more comfortable and safer than the commonly used built-in models. The main concern was the potential for water to splash on clothes from the high faucet.Originality/valueIn addition to showing an innovative design for a purpose-made sanitary fixture for ablution, the study makes the reader aware of the various challenges of providing a hygienic, safe and comfortable facility for users to perform this function. This is very useful for the many designers and facility managers who deal with the issue.

Protective and Comfort Performance of Fire Protective Clothing

The study examined the fire protection performance of several woven products. Given that the comfort and fire protection properties of fire protective clothing (FPC) are opposite, it is important to consider the specific needs of firefighters when selecting the most suitable structure from various plain-woven derivatives, such as plain, basket, and ripstop. The yarn used was Nomex IIIA, which is a type of meta-aramid fibre. To achieve different thread densities, the pick density was adjusted while keeping the end density constant. The physical characteristics, thermal protective performance, thermal resistance, thermal conductivity, water vapour transmission rate and air permeability of all samples were assessed according to the appropriate standards. The goal was to identify the weave structure with the highest performance and the most optimal thread density. The basket weave structure was proposed as a fire protective clothing (FPC) having comfort qualities at a moderate level. Furthermore, increased density provided enhanced fire resistance, however, comfort must be sacrificed. Thus, to achieve a balance between fire protection and comfort, it was recommended to choose a thread density that is of an average level and the suggestion made by this research is to use the fabric as a basket weave design with an ends per inch of approximately 42, it is recommended to retain the pick density within the range of 46 with 44 tex Nomex IIIA yarn. The results of this study may be replicated in other designs using Nomex IIIA and comparable types of cloth and weave specifications.