Ceiling Height Research Articles

Designing affective workplace environments: The impact of typology, contour, ceiling and partition height on cognitive and aesthetic appraisal

Up to 90 % of our time is spent indoors, with 40 % of a full-time employee's waking hours spent at work, underscoring the critical importance of workplace environments in promoting health and well-being. While there is substantial knowledge about the impact of spatial design on environmental satisfaction and productivity, there is a gap in understanding its effect on employees' aesthetic and cognitive experiences. This study addresses these gaps by investigating how variations in typical workplace design elements—such as partition height, ceiling height, and contour shape—across three workplace typologies (Open plan, Cellular, and Bürolandschaft) influence both aesthetic (beauty, attention, pleasure) and cognitive (safety, distraction, interaction) appraisals. Thirty-six virtual models of workplace environments were generated using parametric modeling methods, and a total of 713 participants provided ratings and rankings for these dimensions. Our findings indicate that higher partitions are associated with greater perceived safety and reduced distractions, while curved contours are perceived as more aesthetically pleasing and enjoyable compared to angular designs. The Bürolandschaft typology significantly enhances perceived safety and interaction. Moreover, isovist analysis revealed that spatial features such as isovist compactness and circularity positively correlate with beauty, pleasure, and attention, while higher dispersion is linked to lower safety perceptions. These insights are crucial for designing affective workplace environments that balance openness and privacy, enhance safety, and support a science-informed approach to workplace design that promotes positive cognitive and aesthetic experiences.

Assessment of heat stress contributing factors in the indoor environment among vulnerable populations in Klang Valley using principal component analysis (PCA)

Rising global temperatures can lead to heat waves, which in turn can pose health risks to the community. However, a notable gap remains in highlighting the primary contributing factors that amplify heat-health risk among vulnerable populations. This study aims to evaluate the precedence of heat stress contributing factors in urban and rural vulnerable populations living in hot and humid tropical regions. A comparative cross-sectional study was conducted, involving 108 respondents from urban and rural areas in Klang Valley, Malaysia, using a face-to-face interview and a validated questionnaire. Data was analyzed using the principal component analysis, categorizing factors into exposure, sensitivity, and adaptive capacity indicators. In urban areas, five principal components (PCs) explained 64.3% of variability, with primary factors being sensitivity (health morbidity, medicine intake, increased age), adaptive capacity (outdoor occupation type, lack of ceiling, longer residency duration), and exposure (lower ceiling height, increased building age). In rural, five PCs explained 71.5% of variability, with primary factors being exposure (lack of ceiling, high thermal conductivity roof material, increased building age, shorter residency duration), sensitivity (health morbidity, medicine intake, increased age), and adaptive capacity (female, non-smoking, higher BMI). The order of heat-health vulnerability indicators was sensitivity > adaptive capacity > exposure for urban areas, and exposure > sensitivity > adaptive capacity for rural areas. This study demonstrated a different pattern of leading contributors to heat stress between urban and rural vulnerable populations.

The effect of classroom size and ceiling height on college students’ learning performance using virtual reality technology

The physical characteristics of classrooms can significantly impact the physical and mental health as well as the learning performance of college students. This study investigates the effects of classroom size and ceiling height on learning performance using virtual reality technology. Four classroom settings were created: two small classrooms (40.5 m2) with ceiling heights of 3.0 m and 3.9 m, and two large classrooms (62.1 m2) with ceiling heights of 3.9 m and 4.8 m. 34 students participated in task tests while their subjective evaluations and physiological data were recorded. Results showed higher subjective ratings in larger classrooms with the same ceiling height. Classroom size did not significantly affect task test scores. However, there is a significant difference in Task test scores for ceilings of different heights with the same size classroom. The task test improved by 17.3% in the Big and High Room (BHR) and by 20.1% in the Small and Low Room (SLR). Physiological data revealed significant effects of ceiling height, with HRV-nLF/nHF and EEG-β power increasing by 26.5% and 53.9% in BHR, and by 10.7% and 22.8% in SLR, respectively. This study concludes that classroom size and ceiling height plays a crucial role in learning performance and provides insights for classroom design. It also establishes a framework for future research on the interplay between heart rate variability, EEG, and learning performance.

Relationship between living rooms with void spaces or partially high ceilings and psychological well-being: A cross-sectional study in Japan

In a building environment, it can be inferred that not only the size of the space but also its height influences the well-being of the occupants through their daily living space. However, few studies have investigated the relationship between perceived ceiling height and occupant's well-being in residential environments. Therefore, this cross-sectional study aimed to investigate the relationship between perceived ceiling height in living spaces and well-being in the general population. A total of 3859 Japanese aged 20–69 years were included in the analysis through an online survey. Psychological well-being was assessed using the World Health Organization-5 Well-Being Index, and the perceived ceiling height was based on whether the living space had a void space or a partially high ceiling. The relative risk (RR) and 95 % confidence interval (CI) of perceived ceiling height for poor psychological well-being were estimated using a modified Poisson regression. A significant association was found between higher living room ceilings and better psychological well-being, especially for taller males (RR 0.894, 95 % CI 0.894–0.960). This association was consistent across different housing types, including detached house (RR 0.905, 95 % CI 0.829–0.988) and apartments (RR 0.849, 95 % CI 0.745–0.968). In contrast, no similar association was found among shorter males and females. These findings suggest that taller people, especially males, may benefit psychologically from living in high-ceiling dwellings.

Ascending Performance of Scientific Balloons with Buoyant Gas–Air Mixture Inflation for Designated Ceiling Height

This paper aims to investigate a new method that uses buoyant gas mixed with air to control the floating height of scientific balloons. Firstly, the static characteristics and thermophysical properties of mixed-gas balloons are analyzed. Subsequently, the inflation model and the thermal-dynamic coupled model are established. Furthermore, based on theoretical research, a GUI program is compiled to simulate the ascent of mixed-gas balloons. Finally, flight tests are conducted. As the balloon volume expands to the maximum, the vertical velocity begins to decay and eventually oscillates around 0 m/s, which is consistent with the simulation. In addition, there is a noticeable shift in which the balloon starts to float after climbing to the target altitude, and the difference values between the test and the simulation are less than 350 m. Moreover, the trajectory results are similar to the prediction, and the errors of the end position are less than 2.5 km in horizontal distance. Consequently, this paper provides guidance for balloon-designated ceiling height technology which can allow a single balloon system to be used for tests at multiple heights.

Tasks and Prospects for the Development of the Russian Construction Industry

The main requirements for modern housing are accessibility, quality and aesthetics. In construction, new requirements arise for the technology of manufacturing structures: a free layout with a ceiling height of 2.7 m or more; column pitch of 6 m or more; ceiling height of the first floor up to 8 m; a high degree of factory readiness and architectural aesthetics of the exterior walls. At the same time, it is necessary to ensure a reduction in the weight of structures per 1 m2 of building area and an increase in installation speed. All these requirements can be fulfilled by the Recon technology, known in the practice of the construction industry in Russia and neighboring countries, which produces pre-stressed floor slabs up to 7.65 m long and unstressed floor slabs up to 7.2 m or more; efficiency structures, internal walls (IW) and external walls (EW) on universal stands 3.6; 4; 5.2 m х 60, 90, 120, 128 m in automatic mode, starting with laying concrete using targeted feeding, automatic vibration of the stand surface, grout of the upper surface and automatic heating of the stand. It is important to note that during the hydration of cement stone, the concrete laid on a universal stand does not move either horizontally or vertically, thereby ensuring high quality and density of the product.

Heavy migration traffic and bad weather are a dangerous combination: Bird collisions in New York City

Abstract Bird–building collisions account for 365–988 million bird fatalities every year in the United States alone. Understanding conditions that heighten collision risk is critical to developing effective strategies for reducing this source of anthropogenic bird mortality. Meteorological factors and regional migration traffic may increase collision rates but also may be difficult to disentangle from other effects. We used 5 years of bird collision counts in New York City to examine the influence of nocturnal weather conditions and bird migration traffic rates on collisions with buildings during spring and fall. We found that seasonally unfavourable winds and conditions that impede visibility are important factors that increase the rates of bird–building collisions during both seasons. Specifically, northerly and westerly winds and low visibility in the spring and southerly and westerly winds and low cloud ceiling height in the fall are associated with higher collision risks. Generally, these weather variables associated most strongly with increased collisions when nocturnal bird migration traffic was high, with the exception of low visibility in spring, which was predicted to triple collision rates compared to high visibility, independent of bird migration traffic. Synthesis and applications: Although legislation to turn off unnecessary nocturnal lighting for the entirety of the migration seasons may be an ultimate goal, a proximate goal invaluable for reducing collisions will be predicting which nights will be of highest risk and using this information to determine when mitigation efforts could be most effective.

Ceiling effect of flapping wing rotorcrafts to enable energy-efficient perching

Flapping wing rotorcrafts (FWRs) combine both the motion characteristics of flapping and rotary wings, exhibiting high aerodynamic efficiency at low Reynolds numbers. In this paper, the ceiling effect of FWRs has been studied through numerical and experimental methods to further investigate the aerodynamic performance of FWRs operating under a ceiling and to explore the feasibility of enhancing the flight efficiency of FWRs via ceiling-effect-based perching locomotion. Based on the momentum theory and blade element methods, a theoretical model is first established to predict the additional thrust generated by the FWR operating under the ceiling. Additionally, to uncover the detailed aerodynamic mechanisms of FWRs' ceiling effect, the computational fluid dynamics (CFD) simulations were conducted to analyze the changes in force production and flow field around the FWR at 75–115 mm distances from the ceiling. Furthermore, experimental methods were employed to validate the theoretical model and CFD simulation. The results demonstrate a continuous increase in the thrust from 19.18 to 22.15 gf as the ceiling distance decreases, while the total energy consumption remains relatively constant. Leveraging the ceiling effect, the tested FWR could achieve an additional lift force of up to 9.5% at 75 mm ceiling height with a 33 Hz flapping frequency. Finally, a ceiling perching demonstration was conducted to validate the feasibility of achieving FWRs' energy-efficient locomotion based on ceiling effects. Our study highlights the positive influence of ceiling effect on FWRs, showing a promising way to further improve the flight efficiency of FWRs.

Methods for Selecting Design Alternatives through Integrated Analysis of Energy Performance of Buildings and the Physiological Responses of Occupants

We propose a technique that allows designers to develop energy-efficient buildings focused on occupants from the early design stage. The technique integrates the physiological responses of occupants and the energy performance of buildings. Among the architectural design elements, we considered the aspect ratio, ceiling height, and window-to-wall ratio as design variables and created 30 design alternatives for a single-occupancy room in a postpartum care center. These design alternatives were recreated in virtual reality, allowing 33 female participants to immerse themselves in the designed rooms. During the experiment, we collected electroencephalography (EEG) data from the participants. Furthermore, we used DesignBuilder to simulate 30 design alternatives and calculated the primary energy consumption per unit area for each alternative. By integrating the EEG data and energy performance analysis, we identified the design alternative among the 30 options that positively influenced the physiological responses of occupants while also being energy efficient. The selected alternative was designed with an aspect ratio of 1:1.6, a ceiling height of 2.3 m, and a window-to-wall ratio of 60%. This research represents a creative exploration that demonstrates how studies combining human physiological responses and architecture can evolve through integration with other subjects. Our findings provide a robust framework to explore the relationship between physiological responses and energy optimization for detailed architectural design elements.

Investigation on the burning behaviors of the combustible ceiling with the impingement of an incipient fire source

This paper presents experimental and theoretical research on ceiling jet, burn-through, and flame spread behaviors of the combustible ceiling with the impingement of an incipient fire source. Medium-density fiberboard was utilized as the combustible ceiling in experiments, and the ceiling height above the fire source was varied. The flame radial length (rf), ceiling surface temperature, flame shape and spread rate after burn-through, and radiative heat flux were measured. Results showed that rf beneath the combustible ceiling was significantly longer than that of the non-combustible ceiling. Theoretical analysis was conducted for rf based on energy distribution, and an expression of rf beneath combustible ceiling was proposed. The burn-through behavior of the combustible ceiling was explored by combining the ceiling temperature, small-sized experiment and Fourier law. The advancement of char front along the ceiling thickness was calculated, which was the key point during burn-through. Upper surface flame spread in a circular shape after burn-through, and an expression of spread rate was obtained. A three-dimensional radiation model was adopted to calculate the radiative heat flux received by the unburned ceiling surface during the dynamic flame spread process, the calculated results agreed well with the experimental data.

Optimizing thermal comfort in physical exercise spaces: A study of spatial and thermal factors

Fitness centers have become famous for maintaining a healthy lifestyle. They require different thermal comfort conditions and higher fresh air supply rates than other indoor spaces. However, even well-designed centers may cause discomfort due to factors such as design decisions, ventilation, overheating, and overcrowding. The standards for fitness centers do not consider these specific requirements sufficiently, so this study focuses on understanding the thermal comfort requirements during physical exercise and evaluating spatial and thermal factors affecting the thermal environment around the body. The study investigated the ceiling height, lateral and frontal distances between machines, and vent locations as spatial factors and inlet temperature and air velocity as thermal factors. A thirty-minute moderate-intensity constant work rate exercise test was conducted in a controlled climatic chamber using a cycle ergometer with six healthy male participants. The experiment conditions were simulated in CFD software using the collected data. Once a validated simulation model was provided, computational models for different environmental and spatial scenarios for the five-person cycling class were generated. Using Taguchi L9 (34) orthogonal arrays method, nine spatial scenarios were simulated with three different thermal operations each. Optimal factor levels were determined by using thermal comfort conditions (based on predicted mean vote) around the body’s thermal plume. The results showed that a ceiling height of 5 m, lateral and frontal distances of 1 m and 0.5 m between machines, and Type 2 (two inlets mounted on the ceiling) ventilation strategy were optimal for achieving better thermal comfort values in a thermal condition of 18 °C and 0.2 m·s−1. The study found that increasing the ceiling height and using cross-positioned vents that project air vertically from the ceiling improved the comfort conditions significantly. It is expected that these criteria, which were determined, compared with the standards and detailed, will contribute to the production processes of comfortable exercise spaces.

Numerical safety and performance analysis of a multipurpose building’s structure: case study

This report presents a case study of a multi-use building situated in Brasília-DF. The building's structural model is made up of elements of a spatial portico and four-knot plate, measuring 25.75 by 25.75 m with a height of 11.65 m. The structure is supported by rotating pillars at the base. The ground floor has a ceiling height of 3.25 m, while the other floors have a ceiling height of 2.80 m. The closure is made of bored brick masonry. In this article, numerical analyses were conducted using the SAP2000 structural software to verify the structure's displacement, deformation, and stress. The study followed the ultimate and in-use limit state criteria for the Brazilian standard of reinforced concrete (NBR 6118). The report also presents the building's structural pathologies, detected through visual inspection. The main structural elements and their respective pathologies are described, and numerical tests are shown. Due to the presence of various cracks and other pathologies in the building, an elastic instability analysis was conducted using the Rankine-Marchant analysis model to verify the collapse load factor. After approximately 17 years of use, the building is revisited to assess the durability and performance of the recovered structural components and procedures.

Fire testing methodology to develop solutions for storage and ceiling heights exceeding laboratory limits

The maximum ceiling height of the FM Global laboratory is 18.3 m. Therefore, fire protection solutions for warehouses with taller ceilings cannot be directly validated through full-scale testing. This work develops a methodology to obtain the key processes of fire growth, spray-plume interaction, and fire suppression response for an 18.9 m high roll-paper storage under a 24.4 m tall ceiling. The proposed methodology uses a heptane burner assembly at the base of the commodity array to match the fire heat release and growth rate to that of a taller storage exceeding lab capability. The burner assembly included six heptane burners and two air ducts. A series of experiments was conducted to characterize the burner design, model the fire growth in the free-burn stage, and validate controlled and uncontrolled fires in terms of the number of activated sprinklers. A final large-scale fire test used a 12.8 m high storage of Kraft paper with the burner assembly under an 18.3 m tall ceiling to validate protection recommendations for Kraft paper stored 18.9 m high under a 24.4 m tall ceiling. The test demonstrated full suppression using K360 (K-factor, lpm/bar1/2), fast response, pendent sprinklers with a temperature rating of 74 °C, supplied with a water pressure of 8.3 bar.

Prediction accuracies of ray-tracing and regression models in open-plan offices

The purpose was to determine the prediction accuracies of an empirical regression model (Model 1) and a ray-tracing model (Model 2) in acoustically different open-plan offices. The measurement data was obtained from an open-plan office (81 m2) in which 22 completely different room acoustic conditions were built using alternative room absorption areas in ceiling, walls, and screens, and alternative screen heights. The sound pressure level (SPL) produced by an omnidirectional sound source was measured in six positions in each condition. The corresponding SPLs in 22 conditions were predicted using Models 1 and 2. The prediction accuracies were determined for the A-weighted SPL of speech in each position. In addition, the prediction accuracy was determined for the basic quantities of ISO 3382 standard: spatial decay rate of speech, D2,S, A-weighted SPL of speech at 4 m distance, Lp,A,S,4m, comfort distance, rC, and mean reverberation time T. The mean prediction accuracy of A-weighted SPL of speech was 4.2 dB for Model 1 and 3.4 dB for Model 2. Model 1 predicted D2,S, rC, and T more accurately than Model 2, while the opposite ranking order was found for Lp,A,S,4m. The prediction accuracies of both Models were sufficient when the effects of sound absorption materials and screen heights is simulated. The finding suggests that simple empirical regression models can provide sufficient prediction accuracy in most room acoustic conditions of open-plan offices.

Specifics of the requirements for the interior layout of long-haul aircraft

The plane has become a convenient method of transportation. The main idea of aviation in the 21st century is the safety of passengers and crew. But the human is always inclined towards comfort. The structural and parametric analysis of the long-haul aircraft development made it possible to form the concept of the fuselage layout with capsule accommodation of passengers. The proposed variant of the capsule accommodation, designed for the Boeing 777-200LR, can be installed in other passenger airliners with a ceiling height of at least 2.1 m. Analysis of alternative options for the layout of the passenger compartment allows us to state: with a flight range of more than 8 hours, the flight is comfortable only in business or first classes; the proposed two-story capsule placement allows to provide the layout with first-class seats in a given cabin.

Fabrication of UiTM’s Energy Glider

Glider is a fixed-wing aircraft which does not depend on the engine. A glider can fly for an extended period depending on the design and area of the lifting surface. Just like any other aircrafts, the design of wings is crucial to produce lift force to keep aircraft in the air. Gliders have long wings and is designed to be lightweight which allows it to have a high lift-to-drag ratio (L/D) to glide at a long distance. The maximum lift-to-drag ratio, 〖(L/D〗_max) can indicate how far the glider will glide as it is one of the most important performance parameters. This project aims to design, build, and fly an energy glider. Prior on the design of the energy glider, statistical analysis has been done by comparing data from many studies to aid in determining the initial values of the glider. Then, the general design of the energy glider has been decided during the preliminary design. To support the design decision made, ANSYS Fluent software has been used to study flow of air over KFm-5A aerofoil profile which has been chosen during the early stages of design. The model of the energy glider was then designed in CATIA V5 software with a wingspan of 1.52 m and fuselage length of 0.69 m. Lastly, flight test was conducted to achieve the project’s objective. During the flight test, the glider reached a ceiling height of approximately 300 m and obtained a velocity of 144 km/h. The analysis of the glider performance will be used as an aircraft data for future research.

THE EFFECT OF ARRANGEMENT PATTERNS OF DOWNLIGHT ON FEELING VALUE OF CEILING HEIGHT

In this study, we conducted two subject experiments using virtual environment technology to examine the effect of downlight arrangement patterns on the feeling value of ceiling height. The following findings were obtained. 1) When four downlights are placed on a rectangular ceiling surface, the ceiling height is evaluated higher when the downlights are distributed than when they are gathered in the center. 2) When comparing the color temperature of the downlights at 4000K and 3000K, there is no significant difference in the effect of the placement pattern on the feeling value of ceiling height.

Investigation on favorable pressure gradient in an atmospheric boundary layer wind tunnel using large‐eddy simulation and its impact on wind field and surface pressure measurement

AbstractA constant cross‐section wind tunnel usually experiences a negative pressure gradient (ie, favorable pressure gradient, FPG), resulting in a certain degree of discrepancy between the simulated and idealized atmospheric boundary layer (ABL) flows. To investigate its impact, three large‐eddy simulation (LES) cases were conducted in this study: one simply reproduced a wind tunnel, one removed the FPG by adjusting the ceiling height, and one reduced the FPG by canceling unnecessary boundary layers associated with the tunnel sidewalls and ceiling. The required ceiling height in the second case was estimated based on the pressure gradient in the first case. The FPG was found mainly generated by the contraction effect induced by the boundary layers over the tunnel walls because it can be largely removed in the third case. In addition, we investigated the mean and standard deviation of the surrounding wind field and surface pressure coefficient of an isolated square‐section building model. Because the FPG in the macroscale ABL is negligible compared with the adverse pressure gradient in the microscale near‐wall boundary layers of the building, the influence of the FPG is negligible in a wind tunnel experiment conducted in a relatively large wind tunnel with a safe blockage ratio.

Bat Use of Hollows in California's Old-Growth Redwood Forests: From DNA to Ecology.

The loss of roosting resources, either through disturbance or removal, negatively affects bats. Identifying sensitive species and determining roost requirements are critical components in conserving their habitat. Cavity-roosting bats on the North Coast of California are known to use hollows in large redwood trees. In this study, we examined the factors determining the use of basal tree hollows by different bat species at eight redwood forest sites in Del Norte, Humboldt, and Mendocino Counties, California. Bat guano was collected from 179 basal hollow roosts from 2017 to 2018, and guano mass was used as an index of roosting activity. Nine bat species and one species group were identified by analysis of DNA in guano. We made a total of 253 identifications from 83 hollows into the 10 species categories. The most prevalent species were Myotis californicus (California myotis; 28.5% of all identifications), the Myotis evotis-Myotis thysanodes group (17.4%), Corynorhinus townsendii (17.0%), and Myotis volans (15.0%). We evaluated the extent to which habitat variables at the scales of the hollow, vicinity, and site influenced the level of roost use. The correlations between guano mass and habitat variables were examined using generalized additive mixed models. At the hollow scale, guano mass increased with ceiling height above the opening. At the vicinity scale, guano mass increased with less cover of small trees. At the site scale, there was no association between guano mass and distance to foraging areas, elevation, or the number of nearby hollows. These tree hollow roost preferences can inform land managers when planning the management and conservation of redwood forests.

Directional Measurements and Propagation Models at 28 GHz for Reliable Factory Coverage

Directional measurements of over 2600 links in four distinct factories at 28 GHz are used to formulate the path gain and azimuth gain models to allow reliable 90% coverage estimates. A simple theoretical model of path gain, dependent on ceiling and clutter heights, is found to represent path gain across the four factories with 4.4 dB root-mean-square error (RMSE), contrasted with 6.9 dB slope-intercept fit and 8.5–14.9 dB RMSE for 3GPP factory models. The model also did well against 3.5 GHz path loss data collected over 18 MHz bandwidth in one of the factories, with an RMSE of 3.3 dB. In nonline-of-sight (NLOS) conditions, scattering reduces available antenna azimuth gain from nominal value by up to 7.3 dB in 90% of links. Line-of-sight (LOS) blockage by a 1.7 m × 1 m obstacle in factory aisle leads to 7 dB signal reduction, attributed to availability of other paths. It is found that an access point (AP) using 25 dBm transmit power per polarization, with 23 dBi nominal gain and omnidirectional terminals, supporting <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times $ </tex-math></inline-formula> 2 MIMO in a 400 MHz bandwidth, can provide 130 Mb/s for 90% of factory locations within 50 m.