Personnel Comfort Research Articles

Thermal preference prediction through infrared thermography technology: Recognizing adaptive behaviors

The recognition of thermal adaptation behaviors is a crucial and noninvasive method for accurately and swiftly predicting the thermal preferences of occupants. This is instrumental in enhancing the energy efficiency, indoor personnel comfort, and overall productivity of office buildings. This study employed deep-learning models to analyze a thermal adaptive behavior video dataset captured by Infrared thermography (IRT) cameras to predict the thermal preferences of occupants. A large-scale infrared thermography dataset was developed for recognizing thermal adaptive behaviors using 9650 video samples. Two adaptive behavior recognition models for infrared videos were developed by leveraging neural network models: Two-Stream Inflated 3D ConvNet (I3D) and SlowFast (SF) networks. These models achieved the average prediction accuracies of 83.53 % and 88.56 %, respectively. Notably, both models exhibited a recognition time of milliseconds, facilitating the real-time recognition of thermal adaptive behaviors. This study offers vital technical and theoretical underpinnings for developing decision-making solutions for smart buildings based on noninvasive thermal preference prediction.

Investigation on temperature control performance of an underground confined space under ventilation

The control of thermal environment in underground structures has always been a subject of great concern. In this paper, the influence of initial surrounding rock temperature (ISRT), ventilation temperature (VT) and ventilation volume (VV), as well as internal heat source intensity (HSI) on the temperature control of ventilation risk in underground closed space is explored by building a 50-person Mine refuge chamber (MRC) model with internal heat source. The model is verified according to the experimental data, and the relative deviation is less than 4.3 %. The simulation results show that the indoor temperature (IT) is proportional to the ISRT, HSI and VT, but inversely proportional to the VV. When there are 30 people in the MRC, the ISRT and the initial IT are 32 °C, the VT is 20 °C, and the VV should exceed 450 m3/h to meet the temperature control requirements of 96 h. Taking into account the comfort of personnel, it is recommended that the air volume of 900 m3/h is more appropriate for 30 people.

Power Efficiency using Bank Capacitor Regulator on Field Service Shoes with Fast Charge Method

Power efficiency is a key factor in military equipment, including field service boots used by personnel in various field situations that often demand durability and reliable electricity availability. This research focused on improving the power efficiency of field service shoes by using capacitor bank regulators and fast charging methods. By designing and implementing this system, this research aims to optimize the use of power sources, extend battery life, and improve personnel comfort in the field. The method used in this research is the fast charge method. The fast charge method enables faster battery charging, which is important in field situations with limited time availability. The findings of this research show that the capacitor bank regulator can keep the DC output stable despite instability in the input. The total power usage in the circuit is 0.20 W, and the power efficiency is about 60.61%. The research shows the potential of this voltage conversion circuit for efficient applications. Although it has not achieved maximum efficiency, the capacitor bank regulator can maintain output stability even in input voltage instability. This circuit can effectively cope with voltage conversion in various applications with further optimization.

Experimental study on the influence of environmental parameters on human multi-node warming sensitivity and demand

The thermal comfort of personnel can be improved by optimizing the thermal environmental parameters. And local temperature regulation can enhance the body's comfort in hotter or colder environments. This study systematically investigates the changes in skin temperature, local thermal sensation, and thermal comfort in eight parts before and after heating stimulation under four ambient temperatures and six air velocities, and develops multi-node physiological models of human warming sensitivity and demand. The results indicate that post-stimulation ambient temperature and air velocity have weaker effects on thermal sensation vote and thermal comfort vote than pre-stimulation. The warming demand of the face shows poorer sensitivity to ambient temperature, which is 66.88% lower compared to the abdomen. The air velocity strongly influences the warming demand of the neck, which is 75.01% higher than the lower legs. In addition, the warming sensitivity of the trunk is more influenced by ambient temperature than by air velocity, whereas the extremities' sensitivity is more susceptible to air velocity. The effect of air velocity on warming demand is 2.01–5.91 times greater than the ambient temperature. This study also presents the optimum comfortable temperature and the corresponding equilibrium velocity, providing a certain design basis for pulsating air supply, task-ambient air conditioning, and other variable air supply parameters methods.

The thermal environment and thermal comfort of disaster relief tents in high-temperature composite environment

To ensure the safety and comfort of personnel inside disaster relief tents, this study investigated the distribution of the thermal environment within the tents under composite conditions of high temperature and solar radiation. Furthermore, the interior environmental comfort was evaluated. An experimental platform for tent testing was developed, utilizing a wind tunnel coupled with multiple disaster scenarios and a thermal manikin system. The experiments were conducted under various conditions, including high temperatures and radiation levels of 300 W/m2, 600 W/m2, and 900 W/m2, as well as a wind speed of 1.2 m/s. Two scenarios were considered: doors and windows open or closed. The thermal environmental parameters inside the tent were measured, and the Comfort Prediction Model for Vehicles (CPMV) was employed to assess the thermal comfort of the interior environment. The results indicated a significant temperature rise inside the tent due to the radiation environment, with the maximum top surface temperature reaching 62 °C at 600 W/m2. Notably, a clear temperature stratification was observed among the three horizontal levels inside the tent. Opening the doors and windows resulted in a reduction of temperature below the 1.8 m level. However, when the external radiation intensity exceeded 600 W/m2, the cooling effect was minimal. The temperature stratification phenomenon inside the tent disappeared in the presence of wind, leading to an average temperature decrease of approximately 10 °C. The humidity inside the tent remained lower than the outside humidity. Owing to external irradiation, the black globe temperature inside the tent consistently exceeded the air temperature. The maximum heat flux occurred on the inner side of the tent near the top when the doors and windows were closed, reaching 250 W/m2, while the central heat flux remained relatively stable. When the external radiation during summer was around 300 W/m2, living inside the tent was within an acceptable range. As the radiation exceeded 600 W/m2, the overall thermal sensation became hot, and at 900 W/m2, the interior of the tent became excessively hot and intolerable. In such circumstances, it is recommended to regulate the duration of stay or implement cooling measures to prevent heat stress.

A novel oxygen-enriched method for sentry buildings on plateaus based on an attached jet

Due to the existence of windows and the weak thermal resistance of building envelopes, the sentry building is easily affected by the low-oxygen and low-temperature environment at high-altitudes, which affects the work efficiency, cognitive ability and comfort of personnel. This study proposed a novel oxygen supply method suitable for plateau sentry buildings based on attached jet theory, which can achieve coupling control of the thermal and oxygen environment. The computational fluid dynamics (CFD) method was adopted to study the effect of air supply parameters and oxygen supply concentration on environment creation. The results showed that the environmental creation method could efficiently create the local environment. In addition, a nonuniform oxygen environment is created indoors. That is, the oxygen concentration in the head area is greater than that in the non-head area. It greatly improved the utilization rate of oxygen resources. The influence of the air supply velocity on the indoor environment creation effect is greater than that of the air supply temperature. The effect of creating a local oxygen environment is proportional to the concentration of oxygen supplied. The optimal air supply parameters are an air supply velocity (V) of 3 m/s, air supply temperature (Ts) of 30 °C, and oxygen supply concentration (C) of 90%, with the highest oxygen-enriched velocity of 1.598%/min. The research conclusions will provide new ideas for local environmental control methods in sentry buildings on the plateau and expand to actual projects to solve the problem of engineering application.

A facile spray-pressing synthesis approach for reusable photothermal masks

Certain types of face masks are highly efficient in protecting humans from bacterial and viral pathogens, and growing concerns with high safety, low cost, and wide market suitability have accelerated the replacement of reusable face masks with disposable ones during the last decades. However, wearing these masks creates countless problems associated with personnel comfort as well as more significant issues related to the cost of fabrication, the generation of medical waste, and environmental contaminants. In this work, we present a facile spray-pressing technique for the production of P-masks with a potential scale-up prospect by adding a graphene layer on one side of meltblown fabric and a functional layer on the other side. In principle, this technique could be easily integrated into the present automatic mask production process and the masks have self-cleaning and/or self-sterilizing properties when it is exposed to solar or simulated solar irradiation.

The coupled cooling effect of ventilation and spray in the deep-buried high-temperature tunnel

The utilization of ventilation and spray cooling technology is becoming increasingly popular in high-temperature workplaces due to its convenience and environmental friendliness. To investigate the coupled cooling effect of ventilation and spray in a construction tunnel, we established a droplet evaporation model under convective heat transfer conditions by combining the convective heat transfer theory and the droplet heat and mass transfer model. Based on this model, the study focused on the energy change of droplet evaporation in a moving medium by using numerical simulation in the context of a railroad construction tunnel. The material of the droplets used in the study was water. According to the simulation and field measurement results, it was obtained that, firstly, increased air volume of the tunnel and reduced airflow temperature could make the convective heat exchange stronger between the airflow and the wall. Secondly, the particle size of droplets formed by spraying was mainly 30–40 μm in the tunnel. A part of the droplets was evaporated in the high-temperature environment, and another part was trapped by the rock wall and ground. Third, adopting the coupled cooling method of ventilation and spray, the temperature and humidity fields in the tunnel changed significantly, and a low-temperature and high-humidity zone appeared near the nozzle. At the same time, the evaporation rate of droplets increased, the heat index of the workplace decreased, and the cooling effect was effective. Therefore, the coupled cooling method of ventilation and spray can effectively improve the thermal environment in high-temperature construction tunnels and enhance the thermal comfort of personnel. This study serves as a reference for the parameters and cooling effect of ventilation and spray cooling systems in construction sites.

Development of personal comfort model and its use in the control of air conditioner

The accurate identification of the real-time thermal state of personnel working indoors has been the focus of researchers. In this study, a detailed examination of the entire process of developing a personal comfort model, from theory to practice, is conducted. In particular, the subject of this investigation is a smart air conditioner capable of predicting thermal sensation based on an infrared (IR) sensor that measures the skin temperature of personnel and then implements automatic control. Random forest algorithm was employed to establish a thermal sensation prediction model, which accepts skin and air temperatures as input parameters. The model achieves a high prediction accuracy value of 0.84. Given the measurement errors of low-cost IR sensors, a simulated temperature measurement experiment based on the manikin was conducted, and an error calibration method based on multiple linear regression was developed through the experiment. 30 subjects participated in another prototype test experiment, which proved that the air conditioner can accomplish effective automatic control based on the prediction of thermal sensation, avoid the occurrence of extreme temperatures, and ensure the thermal comfort of personnel. The possible causes of remaining problems and potential improvement schemes are discussed in detail.

Pharmacy personnel comfort and confidence in screening for social needs: A pilot study

BackgroundAddressing social needs (such as lack of adequate housing, food, and transportation) has been shown to improve medication adherence and overall patient outcomes. However, screening for social needs during routine patient care can be challenging due to lack of knowledge of social resources and adequate training. ObjectivesThe primary objective of this study is to explore the comfort and confidence of community pharmacy personnel in a chain community pharmacy when discussing social determinants of health (SDOH) with patients. A secondary objective of this study was to assess the impact of a targeted continuing pharmacy education program in this area. MethodsBaseline confidence and comfort were measured through a brief online survey consisting of Likert scale questions regarding various aspects of SDOH (e.g., importance and benefit, knowledge of social resources, relevant training, workflow feasibility). Subgroup analysis of respondent characteristics was conducted to examine differences between respondent demographics. A targeted training was piloted, and an optional posttraining survey was administered. ResultsThe baseline survey was completed by 157 pharmacists (n = 141, 90%) and pharmacy technicians (n = 16, 10%). Overall, the pharmacy personnel surveyed lacked confidence and comfort when conducting screenings for social needs. There was not a statistically significant difference in comfort or confidence between roles; however, subgroup analysis revealed trends and significant differences between respondent demographics. The largest gaps identified were lack of knowledge of social resources, inadequate training, and workflow concerns. Respondents of the posttraining survey (n = 38, response rate = 51%) reported significantly higher comfort and confidence than the baseline. ConclusionPracticing community pharmacy personnel lack confidence and comfort in screening patients for social needs at baseline. More research is needed to determine if pharmacists or technicians may be better equipped to implement social needs screenings in community pharmacy practice. Common barriers may be alleviated with targeted training programs to address these concerns.

Applications of Nondominated Sorting Genetic Algorithm II Combined with WKNN Online Matching Algorithm in Building Indoor Optimization Design.

The present work aims to improve the comfort of architectural interior design and reduce indoor energy consumption. The Weight K-Nearest Neighborhood (WKNN) algorithm and Nondominated Sorting Genetic algorithm are proposed to locate and analyze the spatial location of indoor personnel and optimize the indoor energy consumption in combination with residential behavior. Firstly, the indoor human behavior data and energy-saving problems are analyzed based on residential behavior theory and architectural physics. The indoor positioning algorithm is proposed to identify the personnel activities to realize the optimization of indoor energy distribution. Secondly, mean filtering and cluster analysis are adopted to optimize sampling points' data and fingerprint database to eliminate data noise. Besides, the WKNN algorithm is used for Wireless Fidelity (Wi-Fi) indoor location fingerprint location. Then, aiming at the multiobjective optimization problem of building indoor energy consumption, the Nondominated Sorting Genetic algorithm obtains the optimal solution of the model. Combined with the indoor location information of personnel, the indoor heating and cooling system is monitored and distributed to reduce the energy consumption in the building while ensuring the living comfort of personnel. The test and simulation results demonstrate that the mean filtering algorithm can solve the room's fluctuation problem of Wi-Fi signals. The cluster analysis algorithm can eliminate the data noise of the fingerprint database and improve the positioning accuracy of the positioning algorithm. Moreover, the location result is independent of the number of nodes; the number of sampling points does not affect the location result. The positioning accuracy of the WKNN algorithm is 2 m, and the positioning error rate within 2 m is about 60%. Compared with other algorithms, the WKNN algorithm has better positioning accuracy and positioning stability. Therefore, the location algorithm designed here can be applied to indoor location optimization. This study provides a reference for optimizing buildings' indoor positioning and energy consumption.

PIV experimental study of airflow structures in a multi-slot ventilation enclosure with opposed jets

The airflow structure of enclosure directly affects the spread of COVID-19 and is also closely related to indoor air quality, thermal comfort of personnel, and building energy consumption. Although a large number of studies on the airflow field have been conducted under mixing and displacement ventilation with a single air inlet in rectangular rooms. However, to the best of the authors knowledge, only a limited number of studies have dealt with airflow structures in a multi-slot ventilation enclosure with opposed jets. Therefore, this paper uses PIV to study the velocity and entropy of unstable airflow field in a multi-slot ventilation enclosure with opposed jets under isothermal and non-isothermal conditions. And this paper presents due to the collision of the jets to form two large-scale eddies, the airflow field structure being unstable. In the region without air supply inlets and exhaust outlets, a large-scale vortex is formed in the airflow field, resulting in high information entropy of the flow field. The thermal plume suppresses the large-scale flow field structure and increases the small-scale flow field structure.

Heat and moisture transfer properties of a firefighter clothing with a new fire-resistant underwear

Under dynamic wear conditions, moisture management and heat transfer behaviour of clothing between the human body and its environment are very important attributes for comfort and performance. Especially considering heavy works like firefighting, it is important to analyse liquid moisture management and thermal comfort properties of fabrics that influence moisture sensation and personnel comfort feeling significantly. This study mainly investigates thermal comfort and moisture management properties of a firefighter clothing with a new fire resistant underwear. Analysing single layer fabric (underwear, outer shell, moisture barrier and thermal barrier) performance properties, together with their three-layered and four-layered combinations gives a better understanding of comfort and protective performance. For characterizing the fabric structures, weight, thickness, FTIR analysis and SEM-EDX tests were conducted. Heat and moisture transfer properties were measured with limited flame spread, thermal resistance (skin model), water vapour transmission rate (dish method), thermal conductivity, air permeability, thermal diffusion, water vapour resistance, moisture management transfer (MMT) and water vapour permeability tests.

Investigation of thermal environment and the associated energy consumption of transportation buildings along the expressways in the cold region of China: A case study

The transportation buildings alongside the expressways (TBE) have comprehensive characteristics, providing shopping and accommodations for drivers and passengers. However, the indoor thermal environment and energy consumption of such service buildings was not covered in most studies. To this end, based on some typical TBEs, this study investigated the thermal environment and energy consumption characteristics for TBEs. And the mentioned TBEs are located in Xiong'an New Area, a national special zone with requirements of low carbon and low energy consumption in China's cold region. The thermal environment study included questionnaire survey and on-site investigation by adopting dynamic thermal comfort evaluation index (i.e., Relative Warmth Index (RWI) and Heat Deficit Rate (HDR)). Then, the TBE energy consumption was investigated with the main influencing factor analyses. Finally, numerical simulations were conducted to analyze the energy efficiency approaches in TBE. The results showed that RWI and HDR were able to evaluate the thermal comfort of personnel in transitional environment of TBE in winter. Meanwhile, when the room temperature was set as 16 °C, it was still able to maintain the thermal environment for the indoor staff. The main energy influencing factors of TBEs are building scale, system equipment and usage characteristics. Besides, it was practicable to adopt the heat pump system to replace conventional space heating and cooling system, of which the total energy consumption of geothermal heat pump reduced by 38.1%.

Study on adaptive thermal comfort of personnel in residential buildings based on tracking test

most of the middle and lower reaches of the Yangtze river in China are hot in summer and cold in winter. In order to study the adaptive thermal comfort of indoor personnel in residential buildings in these areas, a tracking test was conducted on 10 free-running residential buildings in Chongqing from July 2017 to August 2018 through a combination of field test and questionnaire survey. Through the study, in this area, occupants’ evaluations of thermal environment were summarized and analyzed, the relationship between activity level, Clothing insulation and air temperature was established, the thermal neutral temperature and acceptable temperature range in summer and winter were obtained, and the characteristics of adaptive thermal comfort of people in free-running residential buildings were revealed, which provided a reference for improving the thermal environment of residential buildings in the area with hot summer and cold winter in the Yangtze river basin.

Experimental comparison of control methods for armoured personnel carriers with semiactive magneto-rheological suspension

In this study, the control methods of a semi-active magneto-rheological (MR) suspension system for an armoured military vehicle were compared. System modelling and testing procedures were described and then control algorithms were tested and observed on a quarter car test setup, this setup was modified from passive to semi-active system. For tests and simulations, a special off-road profile was formed. This profile was formed depending on the standard military test courses and terrains. During the observation, control ability and personnel comfort were observed as main subjects. Finally, depending on the test results, displacements, accelerations and their effects on subsystems were compared and construed as advantages and disadvantages.

Experimental comparison of control methods for armoured personnel carriers with semi-active magneto-rheological suspension

In this study, the control methods of a semi-active magneto-rheological (MR) suspension system for an armoured military vehicle were compared. System modelling and testing procedures were described and then control algorithms were tested and observed on a quarter car test setup, this setup was modified from passive to semi-active system. For tests and simulations, a special off-road profile was formed. This profile was formed depending on the standard military test courses and terrains. During the observation, control ability and personnel comfort were observed as main subjects. Finally, depending on the test results, displacements, accelerations and their effects on subsystems were compared and construed as advantages and disadvantages.

Role of Ergonomics in Health Care

In the health care field ergonomics has many essential roles to play like, understanding human limitations early in the development of medical devices can reduce errors and avoid performance problems exacerbated by stress and fatigue. Using ergonomics in a design process can reduce the costs of procuring and maintaining products. Ergonomics can minimise the incidence of injury or longer term malaise from poor working environments. An ergonomics task analysis can help identify key components of surgical skill, ensuring that students have affordable, appropriate, valid, and reliable training [2]. Over the period of time health care field undergone tremendous transformation in all the aspects. Despite the success of ergonomics in many areas its contribution in health care field is limited in terms of different aspects like availability, accessibility, geographical distribution, cost-effectiveness as well as user-friendliness. Laparoscopic surgery provides patients with less painful surgery but is more demanding for the surgeon. The increased technological complexity and sometimes poorly adapted equipment have led to increased complaints of surgeon fatigue and discomfort during laparoscopic surgery. Ergonomic integration and suitable laparoscopic operating room environment are essential to improve efficiency, safety, and comfort for the operating team. Understanding ergonomics can not only make life of surgeon comfortable in the operating room but also reduce physical strains on surgeon. The importance of ergonomics in the setting of laparoscopy cannot be over-emphasised. Studies have shown that correct ergonomics can reduce suturing time. Pressurerelated chronic pain among surgeons has been shown to be relieved by the use of ergonomically designed products [3]. As more complex laparoscopic procedures are performed, the need for instrumentation that improves dexterity (degrees of freedom) in an ergonomic manner becomes important [4]. In field of dentistry also ergonomics has important role to play. Proper ergonomic design is necessary to prevent repetitive strain injuries, which can develop over time and can lead to long-term disability. Literature suggests that the prevalence of musculoskeletal pain in dentists, dental hygienists and dental students ranges between 64% to 93%. The successful application of ergonomics assures high productivity, avoidance of illnesses and injuries, and increased satisfaction among workers. Unsuccessful application, on the other hand, can lead to work-related musculoskeletal disorders. Good ergonomic design of tools, processes and furniture does improve personnel comfort, health, morale, productivity and readiness. It is critical to seek prompt medical aid for symptoms of ergonomic stress/ detect risk factors [5]. To conclude, it is imperative to underline the importance of ergonomics developments in the health care field in coming future. More research in ergonomics is needed to help health care personnel to make them more efficient.

Ride Severity Index: A Simplified Approach for Comparing Peak Acceleration Responses of High-Speed Craft

This article presents a simplified approach to quantifying the comparison of acceleration responses of high-speed craft in rough seas. Statistical acceleration values, used to characterize craft seakeeping responses, including average of the highest one-third, one-tenth, and 1/100th peak accelerations and the root mean square acceleration, are used to define the relative Ride Severity Index (RSI). The article first summarizes an unambiguous computational procedure for multiple investigators to calculate similar acceleration values. It then explains the theory and rational for relating statistical acceleration ratios to an indication of potential damage, whether resulting from cumulative wave impacts or single severe slam events, that can be used in comparative assessments of structural integrity, equipment susceptibility to malfunction, or personnel comfort and safety. Example ride severity comparison plots and computed values of RSI are presented to illustrate the simplicity of the approach and to demonstrate the ability to quantify what heretofore has relied primarily on the subjective experience of operators.

Ride Severity Index: A Simplified Approach for Comparing Peak Acceleration Responses of High-Speed Craft

This article presents a simplified approach to quantifying the comparison of acceleration responses of high-speed craft in rough seas. Statistical acceleration values, used to characterize craft seakeeping responses, including average of the highest one-third, one-tenth, and 1/100th peak accelerations and the root mean square acceleration, are used to define the relative Ride Severity Index (RSI). The article first summarizes an unambiguous computational procedure for multiple investigators to calculate similar acceleration values. It then explains the theory and rational for relating statistical acceleration ratios to an indication of potential damage, whether resulting from cumulative wave impacts or single severe slam events, that can be used in comparative assessments of structural integrity, equipment susceptibility to malfunction, or personnel comfort and safety. Example ride severity comparison plots and computed values of RSI are presented to illustrate the simplicity of the approach and to demonstrate the ability to quantify what heretofore has relied primarily on the subjective experience of operators.