Journal articles: 'Weightless environment'

1

Money, Kenneth E., and B. S. K. Cheung. "Alterations of Proprioceptive Function in the Weightless Environment." Journal of Clinical Pharmacology 31, no. 10 (October 1991): 1007–9. http://dx.doi.org/10.1002/j.1552-4604.1991.tb03664.x.

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Ma, Chao, Yu Qing Liu, and Xiu Qing Zhu. "Research of Human Modeling and Motion Simulation Based on ADAMS." Advanced Materials Research 1016 (August 2014): 292–97. http://dx.doi.org/10.4028/www.scientific.net/amr.1016.292.

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The human model in this paper is simplified as a rigid body of 15 segments and the Roberson-Wittenberg method is used to establish the equation of conservation of angular momentum to obtain the control methods of human self-rotation without external force in a weightless environment. And simulation of human dynamic is completed in ADMAS (Automatic Dynamic Analysis of mechanical Systems). The simulation results show that human can generate corresponding body rotation through own limbs rotation in the weightless, and body rotation velocity and angle increase with the moment of inertia and rotational velocity of active body that adds greater torque to joint. Through the analysis of the impact of the angular velocity and torque on the body rotation, a set of self-rotation control strategy for astronaut is proposed in weightless environment.

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Kiselev, M. L., M. A. Zaytsev, V. V. Nesmeyanov, and O. V. Kuzovov. "Overview of Existing Weightless Environment Facilities for Training Cosmonauts." MANNED SPACEFLIGHT, no. 1(34) (March 2, 2020): 120–31. http://dx.doi.org/10.34131/msf.20.1.120-131.

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Takafuji, M., and T. Suda. "Combustion test device of powdered coal under weightless environment." Fuel and Energy Abstracts 43, no. 4 (July 2002): 251. http://dx.doi.org/10.1016/s0140-6701(02)86208-7.

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Zhu, Hui, Hanqing Wang, Chuck Yu, and Zhiqiang Liu. "Effects of simulated weightlessness on thermal sweating of human body: An experimental study." Indoor and Built Environment 28, no. 1 (April 24, 2018): 88–99. http://dx.doi.org/10.1177/1420326x18770501.

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Thermal sweating is the thermoregulatory activity of the human body in hot and warm environments, which is critical to the human thermal comfort and health. The sweating of a human body in a real weightlessness environment has seldom been researched, and simulated weightlessness has usually been conducted under comfortable environments. In order to study the sweating of the human body under weightlessness, a 7-day −6° head down bed rest experiment was carried out on six male subjects lying on their backs to simulate the physiological changes that occur under a weightless environment. The skin microcurrents of the subjects were recorded to evaluate sweating under a range of environments. The results showed that sweating was more significant in the torso and head areas than on the arms and lower body. The whole body sweat rates of subjects were lower than those before the simulated weightlessness experiment. However, the threshold air temperature for the onset of sweating under simulated weightlessness was higher than that before the simulation. This was possibly due to the raising of thermoregulatory set-point temperature of the body. Findings have shown that the sweating behaviour and thermal response of a male human body in a weightless environment could be different to those in the terrestrial condition.

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Seo, Hisao, and Nobuo Matsui. "Hormonal Regulation of Water and Electrolyte Metabolism under Weightless Environment." Biological Sciences in Space 2, no. 2 (1988): 69–79. http://dx.doi.org/10.2187/bss.2.69.

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ITO, Tsuyoshi, Yoshihiko TAGAWA, and Naoto SHIBA. "Maintenance and strengthening of human body musculoskeletal system in weightless environment." Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME 2004.16 (2004): 303–4. http://dx.doi.org/10.1299/jsmebio.2004.16.303.

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Gürel, Zeynep, and Hatice Acar. "Research into Students’ Views About Basic Physics Principles in a Weightless Environment." Astronomy Education Review 2, no. 1 (February 2003): 65–81. http://dx.doi.org/10.3847/aer2003004.

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Zhang, Li-Fan. "Region-specific vascular remodeling and its prevention by artificial gravity in weightless environment." European Journal of Applied Physiology 113, no. 12 (March 24, 2013): 2873–95. http://dx.doi.org/10.1007/s00421-013-2597-8.

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Weiss, Claudia. "Representing the Empire: The Meaning of Siberia for Russian Imperial Identity." Nationalities Papers 35, no. 3 (July 2007): 439–56. http://dx.doi.org/10.1080/00905990701368696.

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Would you like to travel to outer space? Explore like real astronauts the slow, gentle movements characteristic of a weightless environment? The Houston Space Center offers its visitors such a trip through the ISS, the International Space Station. It presents America's space programme by using a simulator to create a compelling environment, complete with 3,000 accurately placed stars that mimic what the real astronauts experience in the ISS.1 You can feel the glory of current-day American scientific progress, the power of the US, the world's number one power.

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Lai, Yi Nan, M. J. Zhao, Y. Dai, M. Z. Lai, and X. Lai. "Design and Simulation of Ground Test Platform for Microsatellite Docking Mechanism." Advanced Materials Research 188 (March 2011): 671–74. http://dx.doi.org/10.4028/www.scientific.net/amr.188.671.

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According to the requirements of the ground demonstration test for small-sized docking mechanism, a set of ground test platform was designed, which can simulate the weightless environment of space and provide six degrees of freedom for the docking mechanism. This paper elaborated the structure and working process of the test platform, and used the way of rigid-flexible coupling to analysis the test platform in dynamics simulation by ADAMS. The mechanical properties of the platform’s key parts during the collision process were obtained

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Al-Saegh, Ali. "Off-line Signature Recognition Using Weightless Neural Network and Feature Extraction." Iraqi Journal for Electrical and Electronic Engineering 11, no. 1 (June 1, 2015): 124–31. http://dx.doi.org/10.37917/ijeee.11.1.13.

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The problem of automatic signature recognition and verification has been extensively investigated due to the vitality of this field of research. Handwritten signatures are broadly used in daily life as a secure way for personal identification. In this paper a novel approach is proposed for handwritten signature recognition in an off-line environment based on Weightless Neural Network (WNN) and feature extraction. This type of neural networks (NN) is characterized by its simplicity in design and implementation. Whereas no weights, transfer functions and multipliers are required. Implementing the WNN needs only Random Access Memory (RAM) slices. Moreover, the whole process of training can be accomplished with few numbers of training samples and by presenting them once to the neural network. Employing the proposed approach in signature recognition area yields promising results with rates of 99.67% and 99.55% for recognition of signatures that the network has trained on and rejection of signatures that the network .has not trained on, respectively.

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Yoshimitsu, Kazuhiro, Naoto Shiba, Hiroo Matsuse, Yoshio Takano, Tohoru Matsugaki, Tomohisa Inada, Yoshihiko Tagawa, and Kensei Nagata. "Development of a Training Method for Weightless Environment Using Both Electrical Stimulation and Voluntary Muscle Contraction." Tohoku Journal of Experimental Medicine 220, no. 1 (2010): 83–93. http://dx.doi.org/10.1620/tjem.220.83.

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Kiselev, Mikhail L., Dmitriy I. Verba, and Valeriy V. Nesmeyanov. "TRAINING OF COSMONAUTS TO CARRY OUT THE EXTRAVEHICULAR ACTIVITY IN WEIGHTLESS ENVIRONMENT TRAINING FACILITY (HYDRO LAB)." Ideas and Innovations 8, no. 3-4 (2020): 82–87. http://dx.doi.org/10.48023/2411-7943_2020_8_3_4_82.

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Zhang, Long Nv, Jia Yin Li, and Yun Yi Wang. "Development and Mobility Evaluation of the Female IVA Clothing." Advanced Materials Research 821-822 (September 2013): 677–80. http://dx.doi.org/10.4028/www.scientific.net/amr.821-822.677.

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Weightless and narrow environment inside the spacecraft and on-orbit work require a lot in astronauts’ IVA clothing. Motion analysis suggests one-piece overall design should base on the curled stance. Toileting structure design which can overcome the one-piece overall’s toileting shortcoming especially for female is essential. 2 female IVA clothing with different structures are developed, then toileting time consuming test and static range-of-motion test are operated to select a better design. Result shows that style 2 performs better when toileting, and not only fits better, but also can provide the same flexibility compare with style 1, which integrates the protection, fitness and mobility.

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16

Pogue, William R. "Living and Working in Space." Proceedings of the Human Factors Society Annual Meeting 30, no. 4 (September 1986): 363–64. http://dx.doi.org/10.1177/154193128603000412.

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Developing an ability to anticipate the various human engineering implications of the weightless (or zero-g) environment of outer space poses a special problem for designers, planners and engineers. This presentation consists of a film entitled, “LIVING AND WORKING IN SPACE”. The film is intended to serve as a training device to create an awareness of zero-g human factors issues. The author is currently serving as a member of the Government Industry Advisory Group (GIAG) for the Manned System Integration Standards (MSIS) study being done under NASA contract and acted as Technical Director for the film which will be a part of the final MSIS package delivered to NASA.

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Weng, He Zhang, Hong Wei Li, Shu Qin Liu, Zhao Liang Cheng, and Jie Liu. "Effects of Surface Crack on Eddy Current Sensor Signal in Maglev System." Applied Mechanics and Materials 278-280 (January 2013): 743–48. http://dx.doi.org/10.4028/www.scientific.net/amm.278-280.743.

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In experiments of mechanical movement in outer space, maglev technology is used for simulating the weightless environment. Maglev rotor moves along a linear guide way. In the process of motion, eddy current sensors are needed for detecting the displacement between sensor and metal guide way. Because of the length requirement of guide way, splicing technique is used. This technique leads to the crack on detective surface and also the distortion of sensor signal. By the means of mathematical model analysis and finite element method, the rules of sensor signal are found out and verified by experiment. The results show that optimal crack width can weaken the distortion of sensor signal.

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AOKI, Hirofumi, Ryuzo OHNO, and Takao YAMAGUCHI. "A STUDY OF SPATIAL ORIENTATION IN A VIRTUAL WEIGHTLESS ENVIRONMENT : Part 2 Causes of spatial cognition errors." Journal of Architecture and Planning (Transactions of AIJ) 68, no. 563 (2003): 85–92. http://dx.doi.org/10.3130/aija.68.85_1.

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19

Jenkin, H. L., J. E. Zacher, M. R. Jenkin, C. M. Oman, and L. R. Harris. "Effect of field of view on the Levitation Illusion." Journal of Vestibular Research 17, no. 5-6 (July 3, 2008): 271–77. http://dx.doi.org/10.3233/ves-2007-175-607.

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Supine subjects inside a furnished room in which both they and the room are pitched 90° backwards may experience themselves and the room as upright relative to gravity. This effect is known as the levitation illusion because observers report that their arms feel weightless when extended, and objects hanging in the room seem to "levitate". This illusion is an extreme example of a visually induced illusion of static tilt. Visually induced tilt illusions are commonly experienced in wide-screen movie theatres, flight simulators, and immersive virtual reality systems. For technical reasons an observer's field of view is often constrained in these environments. No studies have documented the effect of field-of-view (FOV) restriction on the incidence of the levitation illusion. Preliminary findings suggest that when concurrently manipulating the FOV and observer position within an environment, the incidence of levitation illusions depends not only on the field of view but also on the visible scene content.

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20

Harlow, Henry, Tom Lohuis, Thomas Beck, and Paul Iaizzo. "Black Bears in the Wild Retain Muscle Strength During Hibernation." UW National Parks Service Research Station Annual Reports 23 (January 1, 1999): 98–102. http://dx.doi.org/10.13001/uwnpsrc.1999.3381.

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Back bears hibernating through the winter at near normal body temperatures (34Â°C) have limited muscle disuse atrophy. Bears in their natural dens were fitted with a foot torque plate assembly to measure ankle dorsiflexion in response to supramaximal stimulation. Bears lost only 22% of their strength over a 130 day denning period which compares to a predicted 90% strength loss over the same period by humans either confined to bed rest or in a weightless environment. Additionally, six out of 8 muscle twitch parameters altered by muscle atrophy were unchanged by prolonged confinement. Understanding strength retention over an extended period of inactivity by bears has far reaching implications for human medicine and space travel.

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ITO, Tsuyoshi, Yoshihiko TAGAWA, Syoichiro TANAKA, Tetsuya YOSHIDA, Tomohisa INADA, Naoto SHIBA, and Toshiyasu YAMAMOTO. "Development of practical and effective hybrid exercise for use in weightless environment : Ground based models for musculoskeletal atrophy." Proceedings of the JSME annual meeting 2004.6 (2004): 101–2. http://dx.doi.org/10.1299/jsmemecjo.2004.6.0_101.

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Sabah, L., and M. Şimşek. "INVESTIGATION OF SPATIAL DATA WITH OPEN SOURCE SOCIAL NETWORK ANALYSIS AND GEOGRAPHIC INFORMATION SYSTEMS APPLICATIONS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W6 (November 13, 2017): 81–83. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w6-81-2017.

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Social networks are the real social experience of individuals in the online environment. In this environment, people use symbolic gestures and mimics, sharing thoughts and content. Social network analysis is the visualization of complex and large quantities of data to ensure that the overall picture appears. It is the understanding, development, quantitative and qualitative analysis of the relations in the social networks of Graph theory. Social networks are expressed in the form of nodes and edges. Nodes are people/organizations, and edges are relationships between nodes. Relations are directional, non-directional, weighted, and weightless. The purpose of this study is to examine the effects of social networks on the evaluation of person data with spatial coordinates. For this, the cluster size and the effect on the geographical area of the circle where the placements of the individual are influenced by the frequently used placeholder feature in the social networks have been studied.

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Zou, Yupeng, Tao Qin, Nuo Wang, Junqing Li, and Ming Xu. "Passive force control of multimodal astronaut training robot." International Journal of Advanced Robotic Systems 16, no. 3 (May 1, 2019): 172988141984826. http://dx.doi.org/10.1177/1729881419848261.

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For the purpose of solving the problem of astronaut training in weightlessness environment, this article proposes a multimodal astronaut training robot to enable astronauts to perform running, bench press and deep squat training in the weightless environment, so as to help them mitigate the adverse effects brought by the space adaptation syndrome. Taking the modularized wire driving unit as the research object, the dynamic model of the passive force servo system was established; and the passive force control strategy was designed. The experimental results show that the system is of good stability, high steady-state accuracy, and excellent dynamic quality after correction. When the given signal frequency is 10 Hz, the system phase lag is about 9°, and the loading error is about 5%. The passive force servo control strategy can effectively reduce the surplus force. When the speed disturbance frequency of carrying unit is within 3 Hz, the elimination rate of the surplus force can reach 90%.

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SHARMA, GAYATRI, S. K. MEHLA, TARUN BHATNAGAR, and ANNU BAJAJ. "POSSIBLE USE OF FLY ASH IN CERAMIC INDUSTRIES: AN INNOVATIVE METHOD TO REDUCE ENVIRONMENTAL POLLUTION." International Journal of Modern Physics: Conference Series 22 (January 2013): 99–102. http://dx.doi.org/10.1142/s2010194513009975.

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The process of coal combustion results in coal ash, 80% of which is very fine in nature & is thus known as fly ash. Presently, in India, about 120 coal based thermal power plants are producing about 90-120 million tons of fly ash every year. With increase in demand of power energy, more and more thermal power plants are expected to commission in near future and it is expected that fly ash generation will be 225 million tons by 2017. Disposal of fly ash requires large quantity of land, water and energy and its fine particles, if not disposed properly, by virtue of their weightless, can become air born and adversely affect the entire Environment. These earth elements primarily consist of silica, alumina & iron etc. and its physicochemical parameters are closely resembles with volcanic ash, natural soil etc. These properties, therefore, makes it suitable for use in ceramic industries and helps in saving the environment and resources.

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Peng, Yang Lin, Yi Fan Dai, and Shan Yong Chen. "Research on the Support and Gravitational Deformation of Large Aperture Primary Mirror of Space Telescopes." Key Engineering Materials 516 (June 2012): 181–85. http://dx.doi.org/10.4028/www.scientific.net/kem.516.181.

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The surface figure of the primary mirror in a large aperture telescope is one of the key factors influencing imaging quality. Space telescopes are used in weightless environments, which is different from the ground environment for optical machining and testing. Therefore the effect of the deformation induced by gravity on the imaging quality is not negligible and the mirror support is to be carefully designed to unload the gravity during the course of machining and testing. In this paper, finite element analysis software is adopted to simulate and compare the deformation induced by gravity of a metre-scale aspheric lightweight primary mirror with different support methods and different working conditions. The results are then imported into MetroPro software supplied by ZYGO Corporation, to remove the tilts and rigid body motion of the mirror and calculate the primary aberrations from the deformation. Finally, sensitivity analysis of support deformation is implemented and the principles of mirror support design are summarized. The research is instructive for design, machining and testing of large aperture mirrors.

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OHNO, Ryuzo, Hirofumi AOKI, and Takao YAMAGUCHI. "A STUDY OF SPATIAL ORIENTATION IN A VIRTUAL WEIGHTLESS ENVIRONMENT : Part1 Relationship between spatial orientation and the configulation of connected modules." Journal of Architecture and Planning (Transactions of AIJ) 67, no. 558 (2002): 71–77. http://dx.doi.org/10.3130/aija.67.71_2.

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Rioux, Danny, Marie Lagacé, Luchino Y. Cohen, and Jean Beaulieu. "Variation in stem morphology and movement of amyloplasts in white spruce grown in the weightless environment of the International Space Station." Life Sciences in Space Research 4 (January 2015): 67–78. http://dx.doi.org/10.1016/j.lssr.2015.01.004.

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Lackner, James R., and Paul DiZio. "Velocity storage: its multiple roles." Journal of Neurophysiology 123, no. 3 (March 1, 2020): 1206–15. http://dx.doi.org/10.1152/jn.00139.2019.

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Our research described in this article was motivated by the puzzling finding of the Skylab M131 experiments: head movements made while rotating that are nauseogenic and disorienting on Earth are innocuous in a weightless, 0- g environment. We describe a series of parabolic flight experiments that directly addressed this puzzle and discovered the gravity-dependent responses to semicircular canal stimulation, consistent with the principles of velocity storage. We describe a line of research that started in a different direction, investigating dynamic balancing, but ended up pointing to the gravity dependence of angular velocity-to-position integration of semicircular canal signals. Together, these lines of research and the theoretical framework of velocity storage provide an answer to at least part of the M131 puzzle. We also describe recently discovered neural circuits by which active, dynamic vestibular, multisensory, and motor signals are interpreted as either appropriate for action and orientation or as conflicts evoking motion sickness and disorientation.

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Ojrzyńska, Katarzyna. "Whales, Water, and Disability. Towards a Blue Cultural Disability Studies." Przegląd Kulturoznawczy, no. 2 (48) (2021): 268–83. http://dx.doi.org/10.4467/20843860pk.21.019.14076.

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The article explores possible intersections between cultural disability studies and the blue humanities. It opens with a discussion of cultural representations of atypical aquatic mammals and fish. Yet, the main focus is placed on various contemporary literary texts (Mateusz Pakuła’s Wieloryb: The Globe, John Wilson’s From the Depths, and Kaite O’Reilly’s In Water I’m Weightless), which were written either by or for artists with disabilities. As will be shown, all of them allude to water or/and marine environment in order to comment on disability, its social constructedness and context dependence, and the conservation of biological and cultural diversity. In doing so, these texts challenge the fixedness of the disabled/non-disabled binary and subtly hint at a possibility of transgressing the traditional opposition between the human and the animal. This in turn points to the potential of applying the oceanic perspective, or what Philip Steinberg and Kimberley Peters call ‘wet’ and ‘more-than-wet’ ontologies, in disability studies.

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Nakajima, Isao, Masakazu Tachibana, Noriyoshi Ohashi, Hiroshi Imai, Yasushi Asari, and Shigenori Matsuyama. "Emergency Medical Support System for Extravehicular Activity Training Held at Weightless Environment Test Building (WETS) of the Japan Aerospace Exploration Agency (JAXA)." Journal of Medical Systems 35, no. 6 (December 9, 2009): 1343–47. http://dx.doi.org/10.1007/s10916-009-9411-5.

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Arnaud, Sara B., Meena Navidi, Leonard Deftos, Myrtle Thierry-Palmer, Rita Dotsenko, Allison Bigbee, and Richard E. Grindeland. "The calcium endocrine system of adolescent rhesus monkeys and controls before and after spaceflight." American Journal of Physiology-Endocrinology and Metabolism 282, no. 3 (March 1, 2002): E514—E521. http://dx.doi.org/10.1152/ajpendo.00299.2001.

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The calcium endocrine system of nonhuman primates can be influenced by chairing for safety and the weightless environment of spaceflight. The serum of two rhesus monkeys flown on the Bion 11 mission was assayed pre- and postflight for vitamin D metabolites, parathyroid hormone, calcitonin, parameters of calcium homeostasis, cortisol, and indexes of renal function. Results were compared with the same measures from five monkeys before and after chairing for a flight simulation study. Concentrations of 1,25-dihydroxyvitamin D were 72% lower after the flight than before, and more than after chairing on the ground (57%, P < 0.05). Decreases in parathyroid hormone did not reach significance. Calcitonin showed modest decreases postflight ( P < 0.02). Overall, effects of spaceflight on the calcium endocrine system were similar to the effects of chairing on the ground, but were more pronounced. Reduced intestinal calcium absorption, losses in body weight, increases in cortisol, and higher postflight blood urea nitrogen were the changes in flight monkeys that distinguished them from the flight simulation study animals.

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Hill, Richard J. A., Oliver J. Larkin, Camelia E. Dijkstra, Ana I. Manzano, Emilio de Juan, Michael R. Davey, Paul Anthony, et al. "Effect of magnetically simulated zero-gravity and enhanced gravity on the walk of the common fruitfly." Journal of The Royal Society Interface 9, no. 72 (January 4, 2012): 1438–49. http://dx.doi.org/10.1098/rsif.2011.0715.

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Understanding the effects of gravity on biological organisms is vital to the success of future space missions. Previous studies in Earth orbit have shown that the common fruitfly ( Drosophila melanogaster ) walks more quickly and more frequently in microgravity, compared with its motion on Earth. However, flight preparation procedures and forces endured on launch made it difficult to implement on the Earth's surface a control that exposed flies to the same sequence of major physical and environmental changes. To address the uncertainties concerning these behavioural anomalies, we have studied the walking paths of D. melanogaster in a pseudo-weightless environment (0 g *) in our Earth-based laboratory. We used a strong magnetic field, produced by a superconducting solenoid, to induce a diamagnetic force on the flies that balanced the force of gravity. Simultaneously, two other groups of flies were exposed to a pseudo-hypergravity environment (2 g *) and a normal gravity environment (1 g *) within the spatially varying field. The flies had a larger mean speed in 0 g * than in 1 g *, and smaller in 2 g *. The mean square distance travelled by the flies grew more rapidly with time in 0 g * than in 1 g *, and slower in 2 g *. We observed no other clear effects of the magnetic field, up to 16.5 T, on the walks of the flies. We compare the effect of diamagnetically simulated weightlessness with that of weightlessness in an orbiting spacecraft, and identify the cause of the anomalous behaviour as the altered effective gravity.

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Liu, Bingyou, Yi Jin, Changan Zhu, and Changzheng Chen. "Pitching axis control for a satellite camera based on a novel active disturbance rejection controller." Advances in Mechanical Engineering 9, no. 2 (February 2017): 168781401668903. http://dx.doi.org/10.1177/1687814016689039.

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The pitching axis of a satellite camera is controlled under the weightless environment. A novel active disturbance rejection controller is designed to eliminate the influences of the pitching axis. The novel active disturbance rejection controller is designed based on a new nonlinear function, and thus, this function is first established. The function exhibits better continuity and smoothness than previously available functions, hence, it can effectively improve the high-frequency flutter phenomenon. Therefore, the novel active disturbance rejection controller based on the new nonlinear function can eliminate disturbances of the pitching axis. The novel active disturbance rejection controller is composed of a tracking differentiator, a novel extended state observer, and a novel nonlinear state error feedback. The tracking differentiator is used to arrange the transient process. Nonlinear dynamics, model uncertainty, and external disturbances are extended to a new state. The novel extended state observer is utilized to observe this state. The overtime variation of the system can be predicted and compensated using the novel extended state observer. The novel nonlinear state error feedback is adopted to restrain the residual errors of the system. Finally, simulation experiments are performed, and results show that the novel active disturbance rejection controller exhibits better performance than the traditional active disturbance rejection controller.

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Collicott, Steven H. "An Experimenter's Experiences in Early Commercial Suborbital Flight." Gravitational and Space Research 2, no. 2 (December 1, 2014): 66–69. http://dx.doi.org/10.2478/gsr-2014-0017.

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Abstract The emerging commercial suborbital rocket industry in the U.S. presents new opportunities for research and education missions. Some companies have been publicized by the world's media and others are lower-profile. Additionally, some companies were created for the space tourism market and others have no current plans to fly humans at all. Most companies already have a Payload User's Guide published at their websites. The time for experimenters to take note of this industry is now, because in early 2014 a number of these companies were already operational or in flight test phase of their business development. When thousands of dollars, instead of millions for traditional NASA or European Space Agency (ESA) sounding rockets, are needed for a suborbital flight, many more researchers will be able to afford suborbital testing and research. In general, these rocket companies seek to provide at least three minutes of high-quality weightless test times from approximately 60 km to 100 km in altitude, and back to 60 km. Purdue University has been fortunate to have secured numerous launches for small payloads during these developmental and early operational years of the industry. Lessons from these launches include lessons in design, payload environment, procedures, launch site infrastructure, and travel preparations.

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Beltrame, P., V. Travnikov, M. Gellert, and C. Egbers. "GEOFLOW: simulation of convection in a spherical shell under central force field." Nonlinear Processes in Geophysics 13, no. 4 (August 15, 2006): 413–23. http://dx.doi.org/10.5194/npg-13-413-2006.

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Abstract. Time-dependent dynamical simulations related to convective motion in a spherical gap under a central force field due to the dielectrophoretic effect are discussed. This work is part of the preparation of the GEOFLOW-experiment which is planned to run in a microgravity environment. The goal of this experiment is the simulation of large-scale convective motion in a geophysical or astrophysical framework. This problem is new because of, on the one hand, the nature of the force field (dielectrophoretic effect) and, on another hand, the high degree of symmetries of the system, e.g. the top-bottom reflection. Thus, the validation of this simulation with well-known results is not possible. The questions concerning the influence of the dielectrophoretic force and the possibility to reproduce the theoretically expected motions in the astrophysical framework, are open. In the first part, we study the system in terrestrial conditions: the unidirectional Earth's force is superimposed on the central dielectrophoretic force field to compare with the laboratory experiments during the development of the equipment. In the second part, the GEOFLOW-experiment simulations in weightless conditions are compared with theoretical studies in the astrophysical framework's, in the first instance a fluid under a self-gravitating force field. We present complex time-dependent dynamics, where the dielectrophoretic force field causes significant differences in the flow compared to the case that does not involve this force field.

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Lackner, James R. "Spatial Orientation in Weightless Environments." Perception 21, no. 6 (December 1992): 803–12. http://dx.doi.org/10.1068/p210803.

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Illusions of body inversion and of vehicle inversion can be evoked by exposure to weightlessness in the microgravity conditions of orbital and parabolic flight. Such illusions can involve all possible combinations of self-inversion and vehicle inversion. In the absence of any patterns of external stimulation, individuals may lose all sense of body orientation to their surroundings while retaining a sense of their overall body configuration and cognitive awareness of their actual position. Touch and pressure cues provide a perceptual ‘down’ in the absence of visual input. When vision is allowed, apparent orientation is influenced by a variety of factors including the direction of gaze, the architectural layout of the vehicle, and sight of the body. The relative importance of the various factors affecting orientation changes with repeated exposure. The virtual absence of sensations of falling during exposure to free-fall emphasizes the role of cognitive factors in experienced orientation.

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Musgrave, M. E., A. Kuang, L. K. Tuominen, L. H. Levine, and R. C. Morrow. "Seed Storage Reserves and Glucosinolates in Brassica rapa L. Grown on the International Space Station." Journal of the American Society for Horticultural Science 130, no. 6 (November 2005): 848–56. http://dx.doi.org/10.21273/jashs.130.6.848.

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Although plants are envisioned to play a central role in life support systems for future long-duration space travel, plant growth in space has been problematic due to horticultural problems of nutrient delivery and gas resupply posed by the weightless environment. Iterative improvement in hardware designed for growth of plants on orbital platforms now provides confidence that plants can perform well in microgravity, enabling investigation of their nutritional characteristics. Plants of B. rapa (cv. Astroplants) were grown in the Biomass Production System on the International Space Station. Flowers were hand-pollinated and seeds were produced prior to harvest at 39 days after planting. The material was frozen or fixed while on orbit and subsequently analyzed in our laboratories. Gross measures of growth, leaf chlorophyll, starch and soluble carbohydrates confirmed comparable performance by the plants in spaceflight and ground control treatments. Analysis of glucosinolate production in the plant stems indicated that 3-butenylglucosinolate concentration was on average 75% greater in flight samples than in ground control samples. Similarly, the biochemical make-up of immature seeds produced during spaceflight and fixed or frozen while in orbit was significantly different from the ground controls. The immature seeds from the spaceflight treatment had higher concentrations of chlorophyll, starch, and soluble carbohydrates than the ground controls. Seed protein was significantly lower in the spaceflight material. Microscopy of immature seeds fixed in flight showed embryos to be at a range of developmental stages, while the ground control embryos had all reached the premature stage of development. Storage reserve deposition was more advanced in the ground control seeds. The spaceflight environment thus influences B. rapa metabolite production in ways that may affect flavor and nutritional quality of potential space produce.

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Mozdziak, P. E., P. M. Pulvermacher, and E. Schultz. "Muscle regeneration during hindlimb unloading results in a reduction in muscle size after reloading." Journal of Applied Physiology 91, no. 1 (July 1, 2001): 183–90. http://dx.doi.org/10.1152/jappl.2001.91.1.183.

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The hindlimb-unloading model was used to study the ability of muscle injured in a weightless environment to recover after reloading. Satellite cell mitotic activity and DNA unit size were determined in injured and intact soleus muscles from hindlimb-unloaded and age-matched weight-bearing rats at the conclusion of 28 days of hindlimb unloading, 2 wk after reloading, and 9 wk after reloading. The body weights of hindlimb-unloaded rats were significantly ( P < 0.05) less than those of weight-bearing rats at the conclusion of hindlimb unloading, but they were the same ( P > 0.05) as those of weight-bearing rats 2 and 9 wk after reloading. The soleus muscle weight, soleus muscle weight-to-body weight ratio, myofiber diameter, number of nuclei per millimeter, and DNA unit size were significantly ( P< 0.05) smaller for the injured soleus muscles from hindlimb-unloaded rats than for the soleus muscles from weight-bearing rats at each recovery time. Satellite cell mitotic activity was significantly ( P < 0.05) higher in the injured soleus muscles from hindlimb-unloaded rats than from weight-bearing rats 2 wk after reloading, but it was the same ( P > 0.05) as in the injured soleus muscles from weight-bearing rats 9 wk after reloading. The injured soleus muscles from hindlimb-unloaded rats failed to achieve weight-bearing muscle size 9 wk after reloading, because incomplete compensation for the decrease in myonuclear accretion and DNA unit size expansion occurred during the unloading period.

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Mir-Nasiri, N., and B. Almenov. "Design of a Novice Hydraulic Buoyant Force Engine." Applied Mechanics and Materials 705 (December 2014): 71–78. http://dx.doi.org/10.4028/www.scientific.net/amm.705.71.

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In connection with the consumptive depletion of the earth and the destructive effect of emissions of combustion products on the environment, now all of humanity is in search for alternative energy sources. The proposed technology intends to produce electricity directly at the consumer location or in close vicinity to it by utilizing the concept of vertical buoyancy power generation in a still water reservoir and thus able to lower the cost of electricity and save the fossil fuels. The newly invented machine is able to converts the buoyance force energy into mechanical energy of shaft rotation, and thus into the electricity via rotary generator. The hydraulic buoyant force engine system includes two cylindrical pulleys with belt transmission mounted on the stationary frame that is submerged into the water. The belt carries the chain of elastic plastic airbags to generate the buoyance force. The empty and weightless airbags are driven first by the belt and pulleys system to the bottom of a water reservoir where they are filled with the air delivered by the compressor and then the bulged bags and thus connected belt are driven up by the buoyant force. As a result the belt and shaft of the connected to the upper pulley generator will be constantly driven by the buoyant force. The paper describes the details of the engine construction, the amount of power generated by the engine as a function of the reservoir depth and the power of an air compressor as well as advantages of such engine installations and their impact on the society.

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Dalton, P., M. Gould, B. Girten, L. S. Stodieck, and T. A. Bateman. "Preventing annoyance from odors in spaceflight: a method for evaluating the sensory impact of rodent housing." Journal of Applied Physiology 95, no. 5 (November 2003): 2113–21. http://dx.doi.org/10.1152/japplphysiol.00399.2003.

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For the scientific community, the ability to fly mice under weightless conditions in space offers several advantages over the use of rats. These advantages include the option of testing a range of transgenic animals, the ability to increase the number of animals that can be flown, and reduced demands on shuttle resources (food, water, animal mass) and crew time (for water refill). Mice have been flown in animal enclosure module (AEM) hardware only once [Space Shuttle Transport System (STS)-90] and were dissected early in the mission, whereas rats have been flown in the AEM on >20 missions. This has been due, in part, to concerns that strong and annoying odors from mouse urine (vs. rat urine) will interfere with crew performance in the shuttle middeck. To screen and approve mice for flight, a method was developed to evaluate the odor containment performance of AEMs housing female C57BL/6J mice compared with AEMs housing Sprague-Dawley rats across a 21-day test period. Based on the results of this test, consensus was reached that mice could fly in the AEM hardware for up to 17 days (including prelaunch and contingency) and that the AEM hardware would likely contain odors beyond this duration. Human sensory and electronic nose analysis of the AEMs postflight demonstrated their success in containing odors from mice for the mission duration of STS-108 (13 days). Although this paper focuses specifically on odor evaluations for the space shuttle, the concern is applicable to any confined, closed-system environment for human habitation.

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Brownie, Barbara. "Zero-gravity wardrobes: The behaviour of costume in weightless environments." Film, Fashion & Consumption 9, no. 1 (May 1, 2020): 5–21. http://dx.doi.org/10.1386/ffc_00009_1.

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Abstract In this commercial space age, audiences increasingly expect realism in science fiction. Weightlessness is commonly simulated through physical or virtual special effects, but reduced gravity aircraft offer opportunities for capturing the effects of microgravity more authentically. While this poses practical challenges for costume designers, it also invites the possibility of creative engagement with weightlessness. Costume can be employed to visibly evidence the effects of weightlessness, but to take advantage of this opportunity, designers must discard many of the fundamental principles of fashion design. This article examines the effects of weightlessness on costume in sequences shot on board reduced gravity aircraft, from Apollo 13 (Howard, 1995), The Mummy (Kurtzman, 2017), and the music video for OK Go's 'Upside Down & Inside Out' (Kulash and Sie, 2016), as well as footage of real-life astronauts. It then identifies those features of clothing design which must be reconsidered when designing costume for microgravity.

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Leonid Kutsenko, Andrii Kalynovskyi, Oleksandr Polivanov, Andrii Cherniavskyi, and Leonid Zapolskyi. "SIMULATION OF THE ROTATIVE-TRANSLATIVE MOTION OF THE DUMBBELL, WHEN THE CENTER OF ITS MASS MOVES IN A CIRCLE." APPLIED GEOMETRY AND ENGINEERING GRAPHICS, no. 99 (December 17, 2020): 124–44. http://dx.doi.org/10.32347/0131-579x.2020.99.124-144.

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A geometric model of the rotational-translational motion of a dumbbell in a central force field is proposed, provided that its center of mass moves in a circle of a given radius. The term dumbbell denotes a geometric object with two masses spaced apart at a certain distance, connected by a weightless rod (like a sports dumbbell). The idea of modeling is based on the compilation and solution of a system of Lagrange differential equations of the second kind. To compose the equations, the Lagrangian was used to describe the rotational-translational motion of a dumbbell in a central force field. The system of equations is formed with respect to five functions denoting five generalized coordinates. These coordinates connect the fixed and mobile coordinate systems that provide the rotational-translational movement of the dumbbell. The system of Lagrange differential equations of the second kind was solved numerically in the environment of the maple mathematical processor. The results obtained correspond to each of five different coordinate functions that can be plotted graphically. Also obtained are approximate descriptions of the derivatives of these functions depending on the parameters of the dumbbell and the initial conditions of its motion. These results made it possible to construct graphs of phase trajectories of functions of five coordinate coordinates, with the help of which it is possible to determine the nature of the dumbbell movement. The obtained time dependences for the functions of generalized coordinates make it possible to compose an algorithm for computer animation of the rotational-translational motion of the dumbbell. In this case, the parameters of the dumbbell and the initial conditions of its movement will be taken into account. Examples of modeling the trajectories of the centers of mass of the dumbbell weights are given. It is advisable to use the results obtained to illustrate the position of the dumbbell in space when studying its orbital dynamics. Computer animations of a dumbbell movement in zero gravity will make it possible to analyze the influence of the angular velocities of rotation on its movement. At this stage of research, it is advisable to use the results obtained as the basis for laboratory or coursework of the departments of geometric modeling and computer graphics.

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ITO, Tsuyoshi, Shoichiro TANAKA, Kazuyuki TAKEUCHI, Yoshihiko TAGAWA, Naoto SHIBA, and Jeffrey R. BASFORD. "Practical and Effective Exercises on Human Musculoskeletal Systems in Weightless Environments." Transactions of the Japan Society of Mechanical Engineers Series C 71, no. 711 (2005): 3231–38. http://dx.doi.org/10.1299/kikaic.71.3231.

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Lackner, J. R., and P. DiZio. "Human orientation and movement control in weightless and artificial gravity environments." Experimental Brain Research 130, no. 1 (January 3, 2000): 2–26. http://dx.doi.org/10.1007/s002210050002.

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Wren, Ana Vanessa, Nicole Neiman, Martine Madill, Katherine Taylor, Hal Rives, Maria Menendez, Ellen Wang, Thomas Caruso, Samuel Rodriguez, and Linda Nguyen. "P046 MINDFULNESS-BASED VIRTUAL REALITY: A PROMISING MIND-BODY INTERVENTION FOR YOUTH WITH INFLAMMATORY BOWEL DISEASE." Inflammatory Bowel Diseases 26, Supplement_1 (January 2020): S64. http://dx.doi.org/10.1093/ibd/zaa010.164.

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Abstract Background Living with Inflammatory Bowel Disease (IBD) has been associated with increased psychosocial stress among pediatric IBD populations. Elevated psychological stress can exacerbate disease activity and IBD symptoms like abdominal pain, which in turn can negatively impact children’s mental health. There is an increasing need for mind-body interventions that can improve biopsychosocial processes among youth with IBD. Mindfulness-based interventions (MBIs) have been shown to be efficacious in improving emotional distress, pain, and inflammation in a range of pediatric and adult chronic illness/pain populations. Few studies have explored MBIs in pediatric IBD. Using virtual reality (VR) as the medium for an MBI in pediatric IBD has great potential given the increasing prevalence of VR in children’s hospitals, the immersive nature of the technology, and the high acceptability of VR among youth. Aims 1) Assess the feasibility and acceptability of mindfulness-based virtual reality (MBVR) among youth with IBD; 2) Assess the preliminary efficacy of MBVR on anxiety and pain. Methods Youth at an outpatient IBD clinic were offered MBVR. Our team developed a 6-minute MBVR experience, “MediMindfulness-Transitions” (Stanford University & Weightless Studios), that focused participants’ awareness on a natural environment (e.g., waterfall in meadow, northern lights) and their breath. Participants rated their level of anxiety and pain on VAS scales (0-100mm) immediately before and after the MBVR experience. Paired t-tests were used to assess changes in patient reported outcomes (SPSS 26). Patients also completed a satisfaction survey and provided qualitative feedback. Results The sample included 52 participants with IBD (M=15 yrs; 69% Crohn’s disease; 58% Male; 62% White). MBVR was easily integrated into clinic flow (offered before or after MD visit) and there was 100% treatment compliance. There were high levels of enjoyment (M=4.4, range 1–5) and relaxation (M=4.3, range 1–5) post-intervention; 50% of the sample reported MBVR was an ideal length and were extremely interested in using MBRV at home. Qualitative data revealed areas of enjoyment and suggestions for future use (Table 1). Exploratory efficacy analyses revealed MBVR decreased anxiety (16.54 ± 20.56 vs 7.10 ± 13.27, p < 0.001) and pain (9.5 ± 16.19 vs 3.04 ± 6.22, p < 0.01). One patient experienced worsening of their anxiety symptoms. Conclusion MBVR was shown to be feasible and have high acceptability among youth with IBD. The results demonstrated preliminary support for MBVR reducing acute anxiety and pain. This study suggests MBVR could be a promising mind-body therapy for youth with IBD. Future studies should explore the efficacy of MBVR during IBD procedures and treatments (e.g., blood draws, MRIs, infusions) and whether longer-term use of MBVR improves biopsychosocial outcomes.

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Lackner, James R. "Multimodal and Motor Influences on Orientation: Implications for Adapting to Weightless and Virtual Environments1." Journal of Vestibular Research 2, no. 4 (October 1, 1992): 307–22. http://dx.doi.org/10.3233/ves-1992-2405.

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Human sensory-motor control and orientation involve the correlation of sensory information from many modalities with motor information about ongoing patterns of voluntary and reflexive activation of the body musculature. The vestibular system represents only one of the acceleration-sensitive receptor systems of the body conveying spatial information. Touch- and pressure-dependent receptors, somatosensory and interoceptive, as well as proprioceptive receptors contribute, along with visual and auditory signals specifying relative motion between self and surround. Control of body movement and orientation is dynamically adapted to the 1G force background of Earth. Exposure to non-1G environments such as in space travel produces a variety of sensory-motor disturbances, and often motion sickness, until adaptation is achieved. Exposure to virtual environments in which body movements are not accompanied by normal patterns of inertial and sensory feedback can also lead to control errors and elicit motion sickness.

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Kirkpatrick, Andrew W., Jessica Lynn McKee, Colonel Homer Tien, Anthony J. LaPorta, Kit Lavell, Tim Leslie, Paul B. McBeth, Derek J. Roberts, and Chad G. Ball. "Abbreviated closure for remote damage control laparotomy in extreme environments: A randomized trial of sutures versus wound clamps comparing terrestrial and weightless conditions." American Journal of Surgery 213, no. 5 (May 2017): 862–69. http://dx.doi.org/10.1016/j.amjsurg.2017.03.027.

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Dijkstra, Camelia E., Oliver J. Larkin, Paul Anthony, Michael R. Davey, Laurence Eaves, Catherine E. D. Rees, and Richard J. A. Hill. "Diamagnetic levitation enhances growth of liquid bacterial cultures by increasing oxygen availability." Journal of The Royal Society Interface 8, no. 56 (July 29, 2010): 334–44. http://dx.doi.org/10.1098/rsif.2010.0294.

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Diamagnetic levitation is a technique that uses a strong, spatially varying magnetic field to reproduce aspects of weightlessness, on the Earth. We used a superconducting magnet to levitate growing bacterial cultures for up to 18 h, to determine the effect of diamagnetic levitation on all phases of the bacterial growth cycle. We find that diamagnetic levitation increases the rate of population growth in a liquid culture and reduces the sedimentation rate of the cells. Further experiments and microarray gene analysis show that the increase in growth rate is owing to enhanced oxygen availability. We also demonstrate that the magnetic field that levitates the cells also induces convective stirring in the liquid. We present a simple theoretical model, showing how the paramagnetic force on dissolved oxygen can cause convection during the aerobic phases of bacterial growth. We propose that this convection enhances oxygen availability by transporting oxygen around the liquid culture. Since this process results from the strong magnetic field, it is not present in other weightless environments, e.g. in Earth orbit. Hence, these results are of significance and timely to researchers considering the use of diamagnetic levitation to explore effects of weightlessness on living organisms and on physical phenomena.

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Xu, Zhao, Weijie Pan, Yukang Hou, Kailun He, and Jian Lv. "A Decision Tree Model for Analysis and Judgment of Lower Limb Movement Comfort Level." International Journal of Environmental Research and Public Health 19, no. 11 (May 25, 2022): 6437. http://dx.doi.org/10.3390/ijerph19116437.

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To address the problem of ambiguity and one-sidedness in the evaluation of comprehensive comfort perceptions during lower limb exercise, this paper deconstructs the comfort perception into two dimensions: psychological comfort and physiological comfort. Firstly, we designed a fixed-length weightless lower limb squat exercise test to collect original psychological comfort data and physiological comfort data. The principal component analysis and physiological comfort index algorithm were used to extract the comfort index from the original data. Secondly, comfort degrees for each sample were obtained by performing K-means++ to cluster normalized comfort index. Finally, we established a decision tree model for lower limb comfort level analysis and determination. The results showed that the classification accuracy of the model reached 95.8%, among which the classification accuracy of the four comfort levels reached 95.2%, 97.3%, 92.9%, and 97.8%, respectively. In order to verify the advantages of this paper, the classification results of this paper were compared with the classification results of four supervised classification algorithms: Gaussian Parsimonious Bayes, linear SVM, cosine KNN and traditional CLS decision tree.

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Yufita, Evi, Zulfalina -, Muhammad Ilham Nur, Fatriah Fatriah, and Zulkarnain Jalil. "Pengaruh Ekstrak Kulit Buah Naga Merah dan Daun Trembesi sebagai Penghambat Korosi pada Baja A36 dalam Larutan HCl 3%." INDONESIAN JOURNAL OF APPLIED PHYSICS 12, no. 1 (April 12, 2022): 99. http://dx.doi.org/10.13057/ijap.v12i1.54625.

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Tumbuhan merupakan salah satu sumber daya alam yang dapat dimanfaatkan sebagai zat inhibitor organik. Inhibitor organik digunakan untuk mengatasi laju korosi terutama pada material yang mengandung logam. Penelitian ini bertujuan untuk mempelajari peluang beberapa ekstrak dari tumbuhan sehingga dapat dimanfaatkan sebagai inhibitor korosi berdasarkan nilai laju korosi dan efesiensi inhibisi. Tumbuhan yang digunakankan adalah buah naga merah (Hylocereus polyrhizus) dan daun trembesi (Samanea saman (Jacq.). Sampel ujinya berupa plat baja hitam A36 berdimensi 3 cm x 1,5 cm x 1,14 mm, dan medium korosif asam klorida (HCl) 3%. Variasi kosentrasi ekstrak inhibitor untuk masing-masing bahan yang ditambahkan ke dalam medium korosif HCl 3% sebesar 2, 4, 6, 8 dan 10 mL. Perhitungan laju korosi menggunakan metode kehilangan berat (weightloss). Dari hasil penelitian, nilai laju korosi terendah untuk inhibitor ekstrak kulit buah naga merah terdapat pada penambahan inhibitor 10 mL sebesar 0,0463 cm/yr dengan efisiensinya 91,89 %. Sedangkan nilai laju korosi terendah untuk inhibitor ektrak daun trembesi terjadi pada penambahan inhibitor 10ml sebesar 0,0066 cm/year dengan efisiensi 98,9 %. Dari hasil penelitian tersebut dapat disimpulkan bahwa kulit buah naga merah dan daun trembesi mampu menurunkan laju korosi yang terjadi pada baja, sehingga memiliki peluang alternatif untuk dijadikan sebagai inhibitor organik.

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Journal articles on the topic 'Weightless environment'

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