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Background: The last two decades have seen a growing trend toward the use of inflatable membranes for spaceborne structures. The spaceborne inflatable membrane structures are the promising solution for the compact and lightweight reflector antenna. The inflation technique is used for pressurizing the inflatable membrane structure once the satellite reaches to its predefined orbit. Objective: The objective of the study is to demonstrate the use of the residue gas inflation technique for the complete deployment of the inflatable thin membrane boom with different folding patterns. The study also aims to find out generalized relation to calculate the safe mass of residue gases to be kept inside spaceborne membrane boom. Method: The novel analytical relation for the safe mass of residue gases that can be carried for any size of the inflatable boom is established. A comparative study is performed to investigate the effect of variation in a folding pattern on the proposed inflation technique. Experimental, numerical, and analytical approaches were employed for the proposed study. Result: The results show that the total inflation time is inversely proportional to the mass of the residue gases. Through the comparative study, it has been observed that the change in the inflation time is negligible for different folding patterns with the same mass of residue gas. The result confirms that the safe mass of residue gas is successfully deploying the inflatable boom in the vacuum environmental condition keeping the stresses in the boom in the tolerance limit. Conclusions: The findings of this research provide insights into a simple and cost-effective design solution for the inflation system along with safe mass of the residue gases which can be used for any size of spaceborne inflatable boom. [ABSTRACT FROM AUTHOR]

The present work demonstrates the manufacturing process of a pneumatic bellow actuator with an embedded sensor, utilizing a novel manufacturing approach through the complete use of additive manufacturing techniques, such as direct ink writing (DIW) and traditional fused deposition modeling (FDM) methods. This study is innovative in its integration of a dielectric electroactive polymer (DEAP) structure with sensing electrodes made of conductive carbon grease (CCG), showcasing a unique application of a 3D-printed DEAP with CCG electrodes for combined DEAP sensing and pneumatic actuation. Initial experiments, supported by computational simulations, evaluated the distinct functionality of the DEAP sensor by itself under various pressure conditions. The findings revealed a significant change in capacitance with applied pressure, validating the sensor's performance. After sensor validation, an additive manufacturing process for embedding the DEAP structure into a soft pneumatic actuator was created, exhibiting the system's capability for dual sensing and actuation, as the embedded sensor effectively responded to applied actuation pressure. This dual functionality represents an advancement in soft actuators, especially in applications that require integrated and responsive actuation and sensing capabilities. This work also represents a preliminary step in the development of a 3D-printed dual-modality actuator (pneumatic and electrically activated DEAP) with embedded sensing. [ABSTRACT FROM AUTHOR]

This paper evaluates the impacts of different insulation materials on Indoor Air Quality (IAQ) and occupant health with a focus on the Volatile Organic Compound (VOC) emissions. The main aim is to identify options that minimize exposure rates while improving IAQ and energy in retrofitted buildings. A comprehensive literature review was conducted synthesizing scholarly articles, guidelines from international organizations, and information on pollutants, IAQ standards, and retrofit strategies. The findings show high emission rates for some insulation materials that could negatively affect health. Hemp insulation in contrast was identified as a promising solution exhibiting low VOC emissions compared to other insulation materials. As sustainable construction practices advance, hemp insulation emerges as a viable retrofit strategy for social housing by synergistically addressing performance gaps related to energy conservation, air quality, and thermal comfort. The synthesis of evidence from this paper suggests that, from environmental and public health perspectives, certain insulation materials are preferable for improving IAQ and reducing the risk of exposure to indoor air pollutants in retrofitted buildings. [ABSTRACT FROM AUTHOR]

Building air leaks (both through exterior and interior surfaces) can have a significant impact on energy consumption, indoor air quality, fire safety, and moisture accumulation affecting structural durability. Blower door testing has been used to measure leaks in buildings, but commonly used testing methods do not directly measure interior leaks. In this paper, new testing methods (guarded interior test and zonal multipoint pressure testing method) are presented that directly measure these interior leaks, utilizing common blower door equipment for both single and multi-point testing. These new methods are compared to conventional methods in terms of the information provided, limitations and time/effort needed. In addition, building leak measurement results are analyzed to reveal (a) coupling between power law model values (exponent and coefficient) for an ensemble of buildings, (b) the error in using single point testing when estimating low pressure leakage, and (c) how building power law models vary from low to high pressure ranges. [ABSTRACT FROM AUTHOR]

Surface-based inflatables are composed of two thin layers of nearly inextensible sheet material joined together along carefully selected fusing curves. During inflation, pressure forces separate the two sheets to maximize the enclosed volume. The fusing curves restrict this expansion, leading to a spatially varying in-plane contraction and hence metric frustration. The inflated structure settles into a 3D equilibrium that balances pressure forces with the internal elastic forces of the sheets. We present a computational framework for analyzing and designing surface-based inflatable structures with arbitrary fusing patterns. Our approach employs numerical homogenization to characterize the behavior of parametric families of periodic inflatable patch geometries, which can then be combined to tessellate the sheet with smoothly varying patterns. We propose a novel parametrization of the underlying deformation space that allows accurate, efficient, and systematical analysis of the stretching and bending behavior of inflated patches with potentially open boundaries. We apply our homogenization algorithm to create a database of geometrically diverse fusing patterns spanning a wide range of material properties and deformation characteristics. This database is employed in an inverse design algorithm that solves for fusing curves to best approximate a given input target surface. Local patches are selected and blended to form a global network of curves based on a geometric flattening algorithm. These fusing curves are then further optimized to minimize the distance of the deployed structure to target surface. We show that this approach offers greater flexibility to approximate given target geometries compared to previous work while significantly improving structural performance. [ABSTRACT FROM AUTHOR]

In this article, deployable cylindrical vaults of reciprocal linkages with frustoconical ends are analysed. Deployable cylindrical vaults with quadrangular scissors modules have low stiffness in the longitudinal direction, which requires the use of stiffening bars after deployment. The truncated cone-shaped ends improve their stiffness but do not prevent bracing. However, if reciprocal knots are used, the mesh performance improves considerably. This article studies the design conditions of these vaults and their resistance to gravity, wind suction and wind loads in the transverse and longitudinal directions. We also study the different resistance behaviour of the mesh, depending on whether the roof is supported on the upper or lower joints. In all cases, model tests are carried out to check the validity of the proposed solutions. Both theoretical calculations and experimental tests demonstrate the viability and effectiveness of this type of structure. [ABSTRACT FROM AUTHOR]

The climate change observed in the zone of boreal forests of the Holarctic since the end of the 20th century initiates the effect of expanding the boundaries of biological species ranges. Climate-driven invasive processes differ in dynamics. In some situations, there are population outbreaks of unwanted species. In addition to the climatic factor, an important aspect is the response of a biotic environment. Special methods are required to predict rapid invasions that can cause extreme changes. The reproductive potential of pests often turns out to be excessive due to warming climate and favorable conditions. Aggressive invasions often develop as oscillating processes that transform when the species adapts to the environment and fades when the autochthonous biota adapts to a new species. Not only new pests, but also the enemies of the main enemies of ordinary pests have become harmful invaders. Computational scenario models of invasions have been developed based on a logically expandable hybrid structure of equations that take into account delayed adaptation, which is manifested depending on climatic factors as an invasion outbreak develops. The scenarios indicate the series of peaks with fading activity after a primary outbreak and make it possible to evaluate the factors that cause repeated activity of a population after a depression when the invasion of a hyperparasite turns out to be essential. [ABSTRACT FROM AUTHOR]

Microfluidic platforms have revolutionized research in biomedical engineering, enabling efficient and controlled experimentation. Here, we present a novel microfluidic device, the double‐microtube, which offers parallel flow of different fluids. The device is fabricated by transforming a flat structure on a substrate using pneumatic balloon actuator arrays. The inner and outer tubes of the device can be independently controlled, allowing for individual opening and closing of each tubular structure. The inner and outer tubes have diameters of 1 mm and 3 mm, respectively. The device has been successfully tested for cell culture, showcasing its potential application for tubular organ‐on‐a‐chip studies, such as blood vessels and the small intestine. The presented double‐microtube structure promises a new level of control for microfluidic studies, offering exciting opportunities for researchers in the field of biomedical engineering. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Maintaining the airtightness of building envelopes is critical to the energy efficiency of buildings, yet leak detection remains a significant challenge, particularly during building refurbishment. This study addresses the effectiveness of the acoustic beamforming measurement method in identifying leaks in building envelopes. For this reason, an in-field study employing the acoustic beamforming measurement method was conducted. The study involved testing over 30 rooms across three different multi-story office buildings of varying ages and heterogeneous envelope structures. Numerous leaks were located in the façades, which were subsequently visually confirmed or even verified with smoke sticks. The data, captured using an acoustic camera (a microphone ring array), revealed distinct spectra that indicate the method's potential for further research. The basic functionality and the significant potential of this methodology for localizing leakages in large buildings were proven. [ABSTRACT FROM AUTHOR]

This paper presents the design, development, and testing of a robot that combines soft-body grasping and crawling locomotion to navigate tubular objects. Inspired by the natural snakes' climbing locomotion of tubular objects, the soft robot includes proximal and distal modules with radial expansion/contraction for grasping around the objects and a longitudinal contractile–expandable driving module in-between for providing a bi-directional crawling movement along the length of the object. The robot's grasping modules are made of fabrics, and the crawling module is made of an extensible pneumatic soft actuator (ePSA). Conceptual designs and CAD models of the robot parts, textile-based inflatable structures, and pneumatic driving mechanisms were developed. The mechanical parts were fabricated using advanced and conventional manufacturing techniques. An Arduino-based electro-pneumatic control board was developed for generating cyclic patterns of grasping and locomotion. Different reinforcing patterns and materials characterize the locomotor actuators' dynamical responses to the varying input pressures. The robot was tested in a laboratory setting to navigate a cable, and the collected data were used to modify the designs and control software and hardware. The capability of the soft robot for navigating cables in vertical, horizontal, and curved path scenarios was successfully demonstrated. Compared to the initial design, the forward speed is improved three-fold. [ABSTRACT FROM AUTHOR]

This paper presents the development of membrane structures in China. It begins with a historical review of the early applications of membrane structures in the country, highlighting pivotal events and engineering endeavors that contributed to the development. Subsequently, recent advancements in the realm of membrane structures in China are succinctly summarized. The past decade has witnessed notable progress in the implementation of membrane structures, particularly within expansive stadiums and indoor sports arenas. Additionally, cases exemplifying the diverse applications of membrane structures in various projects are presented. Noteworthy among these are the incorporation of membrane structures in building facades, suspended ceilings for indoor spaces, and the utilization of ETFT membrane structures. Furthermore, applications of air-supported membrane structures are explored, especially in the areas of sports facilities and environmental protections. Technical standards and specifications that have played an important guiding role in the development of membrane structures in China are introduced in the last. Finally, 8 issues for the future research and development of membrane structures are pointed out in the conclusion part. It is expected that this paper can serve as a catalyst for further advancement and practical implementation of membrane structures in China. [ABSTRACT FROM AUTHOR]

This paper describes the metrological procedure carried out for the evaluation of the building influence on air temperature measurements. This evaluation aims to produce reliable conclusions, information, and data to contribute to the WMO siting classification schemes for air temperature measurements. For this purpose, a field experiment was designed, deployed, and carried out. As a result, one-year-lasting air temperature measurements were collected and analyzed. In this field experiment, a 200 m wide building is the unique artificial heat source and the unique object projecting shades over a flat surface (no discernible slope) in an open space bigger than 40,000 m2, covered with short grass. Eight calibrated thermometers, equipped with the same model of artificially ventilated radiation shields, were set up at a height of 1.5 m from the ground and at different distances from a 200 m wide building. This configuration provides the observation of the horizontal air temperature radially distributed from the building and, as a conclusion, it enables the quantification of the building influences on air temperature measurements at different distances from the building. This document describes the field experiment, the analysis procedure, the evolution of the building influence on air temperature measurements along the day, and the impact of other meteorological parameters on this building effect. Two different building effects are observed: the positive building effect, where the air temperature decreases with the distance to the building, and the negative building effect, where the air temperature increases with the distance to the building. It is also noticed that the building influence is higher on clear days and the daily maximum building influence values are directly linked with the corresponding maximum solar irradiance. The influence of wind on the building effect is also analyzed, reaching the conclusion that due to characteristic of local winds, in terms of low speed and direction, the wind impact could be considered as negligible. The maximum values of building influence on air temperature measurements, the associated uncertainty analysis, and the conclusions are presented in this paper. All these points have been addressed using metrological principles with the purpose of giving consistency and robustness to the evidence presented here. [ABSTRACT FROM AUTHOR]

Tunable radar stealth structures are critical components for future military equipment because of their potential to further enhance the design space and performance. Some previous investigations have utilized simple origami structures as the basic adjusting components but failed to achieve the desired broadband microwave absorbing characteristic. Herein, a novel double‐broadband switchable microwave absorbing grid structure has been developed with the actuators of inflatable Kresling origami structures. Geometric constraints are derived to endow a bistable feature with this origami configuration, and the stable states are switched by adjusting the internal pressure. An ultra‐broadband microwave absorbing structure is proposed with a couple of complementary microwave stealth bands, and optimized by a particle swarm optimization algorithm. The superior electromagnetic performance results from the mode switch activating different absorbing components at corresponding frequencies. A digital adjusting strategy is applied, which effectively achieves a continuously adjusting effect. Further investigations show that the proposed structure possesses superior robustness. In addition, minimal interactions are found between adjacent grid units, and the electromagnetic performance is mainly related to the duty ratio of the units in different states. They have enhanced the microwave absorbing performance of grid structures through a tunable design, a provided a feasible paradigm for other tunable absorbers. [ABSTRACT FROM AUTHOR]

Rebbachisauridae is a clade of sauropod dinosaurs whose maximum diversification and abundance are known from the Cretaceous of South America. We describe an anterior caudal vertebra, MDPA-Pv 007, from the Upper Cretaceous of Argentine Patagonia, whose characters allow it to be referred to this clade. Also, two phylogenetic analyses reinforce the referral of the new material more exclusively to Rebbachisaurinae. We analyze pneumatic structures using the first CT scans of a caudal element of a rebbachisaurid. The excellent preservation of MDPA-Pv 007, combined with CT images, allows us to document external fossae and foramina that connect to larger internal chambers, constituting unambiguous evidence of pneumaticity. The centrum of MDPA-Pv 007 is camerate, with large interconnected internal chambers; this is accompanied by a neural arch with wide and deep fossae. Caudal pneumaticity has a complex phylogenetic distribution among neosauropods. This feature may have evolved independently in diplodocoids and titanosauriforms, or it could be ancestral for Neosauropoda but secondarily lost in a few lineages. Future investigations, taking advantage of new technologies, will provide insights into the phylogenetic distribution and paleobiological implications of pneumaticity in sauropod dinosaurs and other fossil archosaurs. [ABSTRACT FROM AUTHOR]

Inflatable membrane structures are the state-of-the-art fast evolving space structures owing to its inherent advantages such as lightweight, higher packaging efficiency along with ease of deployment. The membrane reflectors need to be actuated by adequate tension forces to get the required surface accuracy. The design of tensioning device has certain challenges, such as mass penalty, low packaging efficiency and power source dependency. The present study demonstrates the novel design methodology for the tensioning system for the inflatable paraboloid membrane reflector antenna using the wave springs. The loading analysis of the inflatable paraboloid reflector is carried out for adequate inflation pressure and tension forces maintaining the surface error within the tolerance limit. The numerical results of the loading analysis are compared and found to be consistent with the experimental findings. The relation between the displacement of tensioning spring and the dimensions of supporting inflatable torus is established. The results show that wave springs can successfully transfer the required tension forces to the reflector with required surface accuracy. The findings of this research provide insights for simple, lightweight, packaging efficient and cost-effective design solution to the tensioning system for inflatable paraboloid reflector antenna. [ABSTRACT FROM AUTHOR]

In the ever-evolving educational milieu, the integration of innovative teaching methodologies is increasingly crucial to meet the changing needs of modern learners. This research meticulously explores the application of open teaching practices in the fields of building environment and energy application engineering. Through an in-depth examination of multi-regression data pertaining to various environmental factors, this study reveals significant correlations and patterns that are relevant to both educators and environmental specialists. Emphasis is placed on the student-centric ethos of this approach, combining the dual concepts of environmental science and pedagogical progression. The relationship between environmental variables, such as PM2.5, PM10, temperature, and humidity, and the air quality index (AQI) is rigorously analyzed. Such analysis underscores the educational improvements brought about by open teaching strategies. The presented findings not only offer nuanced insights into how the aforementioned variables influence air quality but also highlight the benefits and potential of open teaching methodologies in creating a more interactive and enlightening academic environment. [ABSTRACT FROM AUTHOR]

The majority of existing architecture in Serbia has poor thermal characteristics, and heating systems are mostly based on polluting energy sources. This problem results in the unsatisfactory ecological image of cities, and it is endangering the health of the population. Therefore, improving energy performance is becoming an increasingly common principle of design, within both new and existing buildings. The starting point of this paper is that the use of more than sixteen thousand individual heating systems within single-family households in Užice is one of the most influential air pollutants in the city. The poor quality of energy sources and improper combustion processes release toxic substances into the atmosphere, but the cause of increased emissions of pollutants can be identified in the poor characteristics of thermal envelopes. This research explores whether there is a solution that reduces the pollution in single-family houses by changing the thermal envelope and heating system. The first part of the study points out the main characteristics of the Užice agglomeration, air pollution and energy sources, while the second part describes the selected single-family housing location in the city. The final part of the research examines the impact of various energy improvement measures on the air pollution in the city of Užice. [ABSTRACT FROM AUTHOR]

Street view images are emerging as new street-level sources of urban environmental information. Accurate detection and quantification of urban air conditioners is crucial for evaluating the resilience of urban residential areas to heat wave disasters and formulating effective disaster prevention policies. Utilizing street view image data to predict the spatial coverage of urban air conditioners offers a simple and effective solution. However, detecting and accurately counting air conditioners in complex street-view environments remains challenging. This study introduced 3D parameter-free attention and coordinate attention modules into the target detection process to enhance the extraction of detailed features of air conditioner external units. It also integrated a small target detection layer to address the challenge of detecting small target objects that are easily missed. As a result, an improved algorithm named SC4-YOLOv7 was developed for detecting and recognizing air conditioner external units in street view images. To validate this new algorithm, we extracted air conditioner external units from street view images of residential buildings in Guilin City, Guangxi Zhuang Autonomous Region, China. The results of the study demonstrated that SC4-YOLOv7 significantly improved the average accuracy of recognizing air conditioner external units in street view images from 87.93% to 91.21% compared to the original YOLOv7 method while maintaining a high speed of image recognition detection. The algorithm has the potential to be extended to various applications requiring small target detection, enabling reliable detection and recognition in real street environments. [ABSTRACT FROM AUTHOR]

Introduction: The active implementation of digital technologies in various fields, including in the construction industry, leads to the development of technological platforms to sell multiple products. The study examines the prerequisites for the formation of an organizational and technological platform for monolithic construction using pneumatic formwork, which is a set of material and labor resources and organizational and technological solutions that, through their consolidation with modern digital technologies, allow the implementation of construction projects with specified technical and economic requirements. This study aims to systematize various production and construction solutions, presenting them as a unified organizational and technological system that allows for achieving optimal criteria for construction products. Materials and methods: The factors ensuring its effectiveness were selected and systematized to form an organizational and technological platform. A complex system decomposition is presented at three levels of a hierarchical matrix using the analysis of hierarchies. The level of the stages of the life cycle of buildings and structures is taken as the basis, followed by the level of components of the areas of activity that form the platform's effective formation. At the last, lower level, some factors ensure its effective formation. The analysis of the totality of material and labor resources and organizational and technological solutions that make up the platform for constructing monolithic buildings and structures using pneumatic formwork systems was carried out. Results: For an adequate analytical description, it is proposed to use the a priori ranking method, which makes it possible to decompose the indicated factors influencing the effectiveness of the formation of an organizational and technological platform and to obtain specific criteria and alternatives inherent in the construction of monolithic buildings and structures on pneumatic formwork. The detailed development of an analytical apparatus for obtaining an integral assessment will be the subject of further research. Conclusions: The organizational and technological platform for monolithic construction using pneumatic formwork is an innovative tool for interaction between all participants in implementing such projects, aimed at successfully achieving construction design indicators in terms of time and cost and ensuring the required level of reliability and safety of the constructed facility. The novelty of the proposed approach is determined by the combined consideration of material, technological, organizational, and managerial solutions within a single platform to increase the efficiency of construction product production processes. [ABSTRACT FROM AUTHOR]

The air curtain reduces heat exchange between the two sides by creating a virtual partition and works as a solution for improving building sealing and energy efficiency. Currently, the analytical numerical coupling method has achieved some success in describing the low-order theoretical descriptions of air curtain flow, but its application scope is limited. This paper introduces a data-driven model (DDM) to predict the operation state of the air curtain and the volume flow rate through the entrance. A computational fluid dynamics model is built to generate the dataset, which is validated by comparing velocity and volume flow rate with the published data in the literature. Three of the widely used algorithms are tested: support vector machine, random forest, and backpropagation neural network (BPNN). The main conclusions are as follows: (1) The combination of pressure difference and air supply velocity can quickly determine the operation state of the air curtain in the scene (f1-score = 0.9). (2) A single hidden layer BPNN can achieve high-precision prediction of volume flow rate ( R 2 = 0.92). (3) Compared to theoretical methods, the DDM can retain three-dimensional characteristics of the jet and capture additional details. The approach proposed in this paper can be applied to practical environments to rapidly and accurately optimize the operating parameters of air curtains. [ABSTRACT FROM AUTHOR]

The escalating proliferation of space debris poses an increasing risk to spinning satellites, elevating the probability of hazardous collisions that can result in severe damage or total loss of functionality. To address this concern, a pioneering inflatable protective structure is employed to ensure the optimal functionality of spinning satellites. Additionally, a multi-body dynamic modeling method based on spring hinge unfolding/spring expansion is proposed to tackle the complex dynamics of spinning satellites with inflatable protective structures during flight. This method enables analysis of the motion parameters of spinning satellites. First, the structural composition of a spinning satellite with inflatable protective structures is introduced and its flight process is analyzed. Then, an articulated spring hinge unfolding model or a spring expansion model using the Newton–Euler method is established to describe the unfolding or expansion of the spinning satellite with inflatable protective structures during flight. Finally, the effects on the motion parameters of a spinning satellite are analyzed through simulation under various working conditions. [ABSTRACT FROM AUTHOR]

Intestinal retentive devices have applications ranging from sustained oral drug delivery systems to indwelling ingestible medical devices. Current strategies to retain devices in the small intestine primarily focus on chemical anchoring using mucoadhesives or mechanical coupling using expandable devices or structures that pierce the intestinal epithelium. Here, the feasibility of intestinal retention using devices containing villi‐inspired structures that mechanically interlock with natural villi of the small intestine is evaluated. First the viability of mechanical interlocking as an intestinal retention strategy is estimated by estimating the resistance to peristaltic shear between simulated natural villi and devices with various micropost geometries and parameters. Simulations are validated in vitro by fabricating micropost array patches via multistep replica molding and performing lap‐shear tests to evaluate the interlocking performance of the fabricated microposts with artificial villi. Finally, the optimal material and design parameters of the patches that can successfully achieve retention in vivo are predicted. This study represents a proof‐of‐concept for the viability of micropost‐villi mechanical interlocking strategy to develop nonpenetrative multifunctional intestinal retentive devices for the future. [ABSTRACT FROM AUTHOR]

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Health, well-being, and productivity are the main notions for WELL buildings. Although the WELL building standard does exist to follow when designing a building, the concepts and elements might differ between developed and developing counties and types of buildings. However, there is a lack of knowledge on WELL building concepts and elements in developing countries and residential buildings. Thus, this study uses Malaysia as a case study to investigate the elements that affect health, well-being, and productivity (i.e., WELL) for residential buildings in a developing country. First, semi-structured interviews with built environment industry professionals and individuals living in multi-story residential buildings were carried out. Then, the interview data were analyzed using the thematic analysis technique to generate concepts and elements of WELL for residential buildings in a developing country. The analysis identified nine WELL concepts for residential buildings: air, water, fire, fitness, comfort, mind, safety & security, community, and maintenance & management. Furthermore, the nine themes consist of 53 building elements. The findings suggest three additional new WELL concepts for residential buildings in a developing country: fire, safety & security, and maintenance & management. This is the first study that evaluates the element of WELL for residential buildings that contribute to the existing WELL building standard within the context of a developing country. [ABSTRACT FROM AUTHOR]

The existing large inflatable membrane structure is complex in structure and takes a long time to be extended. In this paper, an air-ribbed skeleton membrane structure is proposed to meet the requirement of camp and emergency tents needing to be set up quickly and easily. Ten single-arch air ribs are arranged side by side to support the tarpaulin, and wind ropes are added to the end and side faces of the tarpaulin to remain stable. The finite element model of the air-ribbed skeleton membrane structure is established to analyze the stress and the displacement of the membrane structure under combined wind and snow loads. The maximum displacement (439.4 mm) and maximum stress (29.94 MPa) are both within the safe standard. The stress and the displacement of the membrane structure in the wind load case is affected by the angle of the wind. The value of maximum stress and displacement at the wind angle of 90° are both lower than those at 0° and 45° in the wind load case. It is advisable to align the site layout of the membrane structure at the wind angle of 90°. The effect of the angle of wind ropes on the stress and displacement of the membrane structure is also studied. The maximum stress and displacement in the case when the angle of wind rope is 30° is smaller than those in the case when the angle of wind ropes is 45°. It is recommended that the wind rope should be laid at 30° to reinforce the membrane structure. [ABSTRACT FROM AUTHOR]

Buildair S.A. has designed, manufactured and built an inflatable hangar (called hangar H75) for the aeronautical industry at Jeddah Airport, Kingdom of Saudi Arabia. H75 is the largest air-cell inflated structure ever built in the world, finally erected in July 2019. The structural analysis and design of the main body of the hangar has involved complex structural concepts due to the specificity of the structural elements employed, like membranes and straps that lead to a highly nonlinear mechanical problem, or the treatment of wind over the structure without a defined standard for inflatable structures. In this article, the structural concept and specificities of the structure are presented, as well as the design procedure for H75 based on numerical analysis, to fulfil the design requirements in terms of stress and deformation of the main body. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Featured Application: The drive and deployment unit of the variable diameter internal drive device described in this paper is primarily intended for use in space deployment structures. This innovative mechanism is expected to serve as a potential deployment mechanism for large-aperture space telescopes, providing the capability to explore distant deep space. The limitations associated with traditional screw-based and cable-based deployment mechanisms for space deployable structures, such as deployment stiffness, accuracy, and distance, are effectively overcome by introducing the concept of a variable diameter internal drive device. To enhance stability during the discontinuous surface transition phase inside the tubular structure, a thin-walled flexible beam structure is adopted for the driving deployment unit. The analysis employs the spatial absolute nodal coordinate formulation, integrating the pose states of each node into the global coordinate system. The three-dimensional displacement field and rotational angle changes at different time intervals are obtained using the unit shape function matrix and Kirchhoff theory. Subsequently, a dynamic model of the corresponding spatial nodes is established using the virtual work principle. This significant improvement enhances the dynamic characteristics of the coupled rigid-flexible deformation of the driving deployment unit under radial and axial external forces, surpassing the previously used flexible beam structure. The dynamic simulation analysis is performed using the finite element method and validated through experimental tests. The experimental results confirm the driving deployment unit's stability and successful achievement of the desired functionalities, as demonstrated by the endpoint displacement, three-dimensional centroid displacement, and trajectory rotation angle. [ABSTRACT FROM AUTHOR]

In order to study the influence of the cavity inclination angle bending performance of pneumatic soft actuators, two kinds of soft actuators were designed, one with a five-degree-angle cavity structure, and the other with a hybrid variable-degree-angle cavity structure. The bending performance of zero-degree-angle, five-degree-angle, and hybrid variable-degree-angle soft actuators was investigated by experimental methods and the ABAQUS finite element simulation method. The results show that, under seven different pressure loads, the mean absolute error between the experimental results and the numerical simulation results for the zero-degree-angle soft actuator was 0.926, for the five-degree-angle soft actuator it was 1.472, and for the hybrid variable-degree-angle soft actuator it was 1.22. When the pressure load changed from 4 kPa to 16 kPa, the five-degree-angle soft actuator had the largest range-of-angle variation, with the bending angle increasing 193.31%, from 26.92 degrees to 78.97 degrees. In the same longitudinal displacement, the five-degree-angle soft actuator had the largest lateral displacement variation, and the bending effect was the best compared with the zero-degree-angle soft actuator and the hybrid variable-degree-angle soft actuator. According to the experimental and numerical simulation results, with the same structural parameter design, the cavity tilt angle increases, which can increase the bending angle variation range and improve the bending performance of soft actuators. [ABSTRACT FROM AUTHOR]

Soft pneumatic gripping strategies are often based on pressurized actuation of structures made of soft elastomeric materials, which limits designs in terms of size, weight, achievable forces, and ease of fabrication. In contrast, fabric‐based inflatable structures offer high stiffness‐to‐weight ratio solutions for soft robotics, but their actuation has been little explored. Herein, a new class of pneumatic soft grippers is presented that exploits the in‐plane overcurvature effect of inextensible fabric flat balloons upon inflation. A star‐shaped gripper contracts radially under pressure producing a gripping force on the object whose intensity can be modulated by the pressure input. First, the kinematics and mechanics of a single V‐shaped actuator are studied through experiments, finite element simulations, and analytical models. Then, these results are leveraged to predict the mechanical response of the entire star, optimize its geometry, and maximize contraction and stiffness. It is shown that the gripping performance can be improved by stacking several stars with silicon‐coated corners. It is expected that the flexibility, robustness, scalability, and ease of fabrication of this methodology will lead to a new generation of lighter and larger actuators capable of developing higher forces and moving delicate and irregularly shaped objects while maintaining reasonable complexity. [ABSTRACT FROM AUTHOR]

Passive cooling technology is currently a hot research topic because it can achieve cooling without external energy input, significantly reduce cooling costs and mitigate global warming. At present, passive cooling technology is mainly used in construction, transportation, electronic equipment, and other fields, but most passive cooling materials do not have gas barrier performance, which limits the application of passive cooling technology in inflatable structures such as gas film buildings, blimp bladders and other fields, so a material that has both passive cooling and gas barrier performance is needed. In this paper, PXTPU composites were prepared by melt blending mica‐TiO2 with thermoplastic polyurethane (TPU). PXTPU not only achieves passive cooling above 10°C with the excellent reflectivity of TiO2 in mica‐TiO2, but also achieves 61.1% or even 74.5% enhancement of gas barrier capacity with the high orientation of lamellar mica in mica‐TiO2. In addition, PXTPU also exhibited good thermal stability and mechanical properties exceeding 31.2 MPa breaking strength and 210.6% breaking elongation. Therefore, PXTPU composites show great potential in inflatable structures for outdoor work, expanding the application field of passive cooling technology. [ABSTRACT FROM AUTHOR]

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In China, the post-Winter Olympics era has seen the rapid development and promotion of ice rinks with air-supported membrane structures. With the rise of large indoor spectator areas in ice rinks, thermal comfort needs in spectator areas are receiving more and more attention. The satisfaction of thermal comfort needs is crucial to people's health and well-being, so further study of the issue of thermal comfort in such spectator areas is needed. Unfortunately, models currently used to evaluate the thermal comfort of traditional building envelopes are not applicable to air-supported membrane-envelope ice rinks. Researchers need to focus on the internal thermal comfort needs of air-supported membrane envelopes for spectator areas. The aim of this research was to establish a thermal comfort model to provide exact temperature-range recommendations for spectator areas in air-supported membrane ice rinks. The indoor thermal-environment parameters of the ice rink in Harbin were measured from 2 January to 15 January 2023. To elicit data on spectators' actual thermal sensations in the ice rink, a field questionnaire was administered. By modifying the expectancy factor, an extended predicted thermal comfort model was established. The results suggested that the operative temperature required to meet spectators' thermal comfort needs in the case study ice rink ranged from 17 °C to 26 °C. The results of the study offer specific insights into the indoor thermal comfort needs of air-supported ice rinks and provide a more accurate temperature-setting reference for the healthy and energy-efficient development of such rinks. [ABSTRACT FROM AUTHOR]

The sauropod genus Mamenchisaurus, from the Late Jurassic–Early Cretaceous of East Asia, has a convoluted taxonomic history. Although included in the first cladistic analysis of sauropods, only recently has the monophyly of Mamenchisaurus, and the anatomical diversity of the many penecontemporaneous East Asian eusauropods, been evaluated critically. Here, we re-describe the holotype and only specimen of M. sinocanadorum. Although the original diagnosis is no longer adequate, we identify several autapomorphies that support the validity of this species, including an elongate external mandibular fenestra and distinctive pneumatic structures on the cervical centra. We incorporate new data into a phylogenetic character matrix that also includes Bellusaurus and Daanosaurus, both of which are known only from juvenile material and are often hypothesized to be neosauropods (or close relatives thereof). We recover all species of Mamenchisaurus as part of a radiation of predominantly Middle–Late Jurassic East Asian eusauropods, but the genus is non-monophyletic, underscoring the need for further systematic revision of mamenchisaurid taxonomy. Analyses that score ontogenetically variable characters ambiguously recover Bellusaurus and Daanosaurus as juvenile mamenchisaurids, a hypothesis supported by several features that are unique to mamenchisaurids or exhibit little homoplasy, including anteriorly bifurcate cervical ribs. Finally, computed-tomography reveals extensive vertebral pneumaticity in M. sinocanadorum that is comparable to that of the largest sauropods, and updated scaling analyses imply a neck over 14 m long, rivalling estimates for other exceptionally long-necked sauropods. Previous work has suggested that the elongated cervical ribs of particularly long-necked sauropods such as M. sinocanadorum stabilized the neck by limiting its mobility. Given that extent of pneumaticity responds dynamically to a bone's habitual loading, we propose that long cervical ribs – and other structural modifications that limited flexibility – promoted the evolution of increasingly long necks by producing a more predictable biomechanical milieu amenable to increased pneumatization. [ABSTRACT FROM AUTHOR]

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Inflatable wings are of interest for applications where low weight, compact transport volume, and easy set-up are important. Examples are unmanned aerial vehicles with inflatable wings, paragliders and softkites for sport or airborne wind-energy applications. In this paper, a new method of designing and fabricating conformable inflatable wings by Jacquard three-dimensional weaving is presented. Depending on the weaving pattern, plane-parallel, tapered, or even curved structures can be produced. An analytical framework was developed to determine the shapes of pressurized structures produced by Jacquard weaving. Based on this theory, several design patterns suitable for inflatable wings are proposed. It is shown that the structural efficiency of the woven structure is identical to the structural efficiency of a cylinder. To validate the concept, different wing prototypes were built with the methods used for the mass production of airbags. The new method allows for the cost-efficient fabrication of inflatable structures, pressure vessels, and liquid containers with applications in the automotive, aerospace, and leisure industries. [ABSTRACT FROM AUTHOR]

The psychrometric chart is the most common data visualization technique for the designers of thermal comfort systems worldwide. From its humble roots as means of expressing the characteristics of air in building systems design, the use of the chart has grown to include the representation of the zones of human thermal comfort according to both conventional and adaptive models. In this paper, we present an extensive history of this development and the fallacies with representing comfort simply as a box that sometimes moves on the chart. The origins of the link between refrigeration control and comfort control are examined through archival reviews, examining the works of Carrier, Yagoglou, and their contemporaries in the context of modern comfort mischaracterizations. A clearer understanding of the mapping of comfort, control, and climate metrics with psychrometrics is reported, and a critique of the conflation is reported to increase awareness of the limitations of such treatment of these three critical domains. [ABSTRACT FROM AUTHOR]

Cable-membrane constructions typically exhibit significant displacement and distortion under load action, and the cable-membrane contact results in relative sliding. In this paper, the interaction force between cable and membrane is transferred through frictional contact action, and as a result, the friction coefficient must be taken into consideration for the form-finding and load analysis of air-supported membrane structures. Eight kinds of P-type membrane materials commonly used in engineering were chosen, and the friction coefficients between the various membrane and cable materials were obtained. The connection between a cable and a membrane of an air-supported membrane structure is considered a contact problem, and its initial shape analysis and wind load response analysis are carried out. The influence of the friction coefficient of a cable membrane on the wind-induced response of an air-supported membrane structure is discussed, and the results are compared with those of the cable-membrane binding model under wind load. [ABSTRACT FROM AUTHOR]

The air supported membrane structure is a typical nonlinear flexible long-span space structure, the wind-induced drift and the resulting accumulation and distribution of snow particles on the structure may be the primary design concern among all loads in heavy-snowfall region. Thus, an accurate prediction of snow distribution on membrane surface is vital to structural design. A numerical simulation method is used to estimate snowdrift in this paper. Based on Euler-Euler method in multi-phase flow theory, this numerical model adopted Mixture model and combined with the snow deposition and erosion model, the snowdrift on an air-supported membrane coal shed is simulated, the distribution factor for roof snow load is given under different wind speed and different directions to estimate the worst load case, snow load on the air-supported membrane structure is significantly affected by snowdrift which causes significant non-uniform snow load. Furthermore, the response analysis of the air-supported membrane structure under snow load is studied, for comparison, uniform snow load case, non-uniform snow load case, and simulated snow load case under 0° wind direction are all considered. The results show that non-uniform snow load caused by snow drifting is more dangerous and should be considered. [ABSTRACT FROM AUTHOR]

The flow structures and surface pressure distributions on corrugated airfoils significantly differed from those on a conventional, smooth airfoil. An unsteady, two-dimensional computational simulation was carried out to investigate the flow behavior and associated aerodynamic performance of a group of corrugated airfoils with different levels of waviness at angles of attack from 0° to 20° with an interval of 2° at a low Reynolds number regime (Re = 1.2 × 105) and were quantitatively compared with those of its smooth counterpart. Time-averaged aerodynamic coefficients demonstrated that the corrugated airfoils have a lower lift and higher drag because of trapped vortices in the corrugations. The pressure drag of the corrugated airfoils was greater than that of the smooth airfoil. In contrast, the viscous drag of the corrugated airfoils was smaller than that of the smooth airfoil because the recirculation generated in the corrugation could reduce the viscous drag. The averaged velocity gradient in the boundary layer showed that the thickness of the boundary layer increased significantly for the corrugated airfoils because of recirculating flow caused by the small-standing vortices trapped in the valley of corrugations. The smoother the corrugated surface, the closer the aerodynamic characteristics are to those of the smooth airfoil. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For several years, kites have been representing an innovative technology in the maritime sector to reduce the fuel consumption through an auxiliary propulsion or producing energy onboard. Regarding the continuous increase in kite sizes, one of the main objectives is to determine whether a leading-edge inflatable kite and its components will be able to withstand the pressure field induced by the aerodynamic load. Therefore, an accurate identification of stress fields in them is required by designers. For this aim, a fluid-structure interaction method was developed by coupling a 3D nonlinear lifting-line model with the Abaqus™ 2017 finite-element software tools. Within this framework, a structural analysis was performed for a kite made of a woven fabric by employing the thin-layer finite-element technique for its weak bending properties. This modeling method is new and is not available in the Abaqus™. [ABSTRACT FROM AUTHOR]

The cable net and membrane of the air-supported membrane structure transmits the load through mutual extrusion, and the contact interaction between the cable net and membrane should be considered in the initial morphological analysis stage. In this paper, a scale model was designed according to a large-span air-supported membrane structure engineering project, and the shape and force of the structure were measured. At the same time, a finite element model of cable–membrane contact was established, and its interaction behavior was regarded as a combined contact state and sliding contact state. The results show that the influence of different contact state analyses on the prestress of the cable net is obvious, and the influence of the sliding contact between the cable and the membrane should be considered in the design of the membrane structure. [ABSTRACT FROM AUTHOR]

The origin of the air sac system present in birds has been an enigma for decades. Skeletal pneumaticity related to an air sac system is present in both derived non-avian dinosaurs and pterosaurs. But the question remained open whether this was a shared trait present in the common avemetatarsalian ancestor. We analyzed three taxa from the Late Triassic of South Brazil, which are some of the oldest representatives of this clade (233.23 ± 0.73 Ma), including two sauropodomorphs and one herrerasaurid. All three taxa present shallow lateral fossae in the centra of their presacral vertebrae. Foramina are present in many of the fossae but at diminutive sizes consistent with neurovascular rather than pneumatic origin. Micro-tomography reveals a chaotic architecture of dense apneumatic bone tissue in all three taxa. The early sauropodomorphs showed more complex vascularity, which possibly served as the framework for the future camerate and camellate pneumatic structures of more derived saurischians. Finally, the evidence of the absence of postcranial skeletal pneumaticity in the oldest dinosaurs contradicts the homology hypothesis for an invasive diverticula system and suggests that this trait evolved independently at least 3 times in pterosaurs, theropods, and sauropodomorphs. [ABSTRACT FROM AUTHOR]