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221.
Beom-Seok Song Jin-Gyu ParkJae-Nam Park In-Jun HanJae-Hun Kim Jong-Il ChoiMyung-Woo Byun Ju-Woon Lee 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Addition of calcium lactate and vitamin C, a mild heating, deep-freezing, and gamma irradiation at 25 kGy were conducted to prepare Kimchi as a ready-to-eat space food. It was confirmed that the space food was sterilized by an irradiation at 25 kGy through incubation at 37 °C for 30 days. The hardness of the Space Kimchi (SK) was lower than the untreated Kimchi (CON), but higher than the irradiated Kimchi (IR). Also, this result was supported by the scanning electron microscopic observation. Sensory attributes of the SK were similar to CON, and maintained during preservation at 35 °C for 30 days. According to the Ames test, Kimchi sterilized with a high-dose irradiation exerted no mutagenic activity in the bacterial strains of Salmonella typhimurium. And, the SK was certificated for use in space flight conditions during 30 days by the Russian Institute of Biomedical Problems. 相似文献
222.
Attitude determination refers to determining the orientation of a vehicle relative to its reference coordinate system. This paper presents a new algorithm for three-axis attitude determination using measurement vectors composed of incomplete vector components. The attitude determination performance of the proposed algorithm is compared with those of the TRIAD and QUEST algorithms in a simulation. 相似文献
223.
Dehbonei H. Lee S. R. Ko S. H. 《IEEE transactions on aerospace and electronic systems》2009,45(1):46-57
This two-part paper presents a comprehensive comparative study on parallel power processing (PPP) and standard schemes in dc/dc converters for photovoltaic (PV) energy systems. It is demonstrated how PPP can improve direct energy transfer (DET), which results in PV systems operating at higher voltage and efficiency. Discussions of the concepts, hypotheses, and computer simulations are presented in Part I. Part II provides the experimental results, which confirm the validity of the analysis and simulations. 相似文献
224.
Susan Jason Alex da Silva Curiel Doug Liddle Francis Chizea Ugur Murat Leloglu Mustafa Helvaci Mohammed Bekhti Djouad Benachir Lee Boland Luis Gomes Martin Sweeting 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
This paper focuses on ways in which space is being used to build capacity in science and technology in order to: 相似文献
225.
B. Klecker H. Kunow H. V. Cane S. Dalla B. Heber K. Kecskemety K.-L. Klein J. Kota H. Kucharek D. Lario M. A. Lee M. A. Popecki A. Posner J. Rodriguez-Pacheco T. Sanderson G. M. Simnett E. C. Roelof 《Space Science Reviews》2006,123(1-3):217-250
The characteristics of solar energetic particles (SEP) as observed in interplanetary space provide fundamental information about the origin of these particles, and the acceleration and propagation processes at the Sun and in interplanetary space. Furthermore, energetic particles provide information on the development and structure of coronal mass ejections as they propagate from the solar corona into the interplanetary medium. In this paper we review the measurements of energetic particles in interplanetary space and discuss their implication for our understanding of the sources, and of acceleration and propagation processes. 相似文献
226.
Tatsuya Arai Kichang Lee Michael B. Stenger Steven H. Platts Janice V. Meck Richard J. Cohen 《Acta Astronautica》2011,68(7-8):770-777
Orthostatic intolerance (OI) is a significant challenge for astronauts after long-duration spaceflight. Depending on flight duration, 20–80% of astronauts suffer from post-flight OI, which is associated with reduced vascular resistance. This paper introduces a novel algorithm for continuously monitoring changes in total peripheral resistance (TPR) by processing the peripheral arterial blood pressure (ABP). To validate, we applied our novel mathematical algorithm to the pre-flight ABP data previously recorded from twelve astronauts ten days before launch. The TPR changes were calculated by our algorithm and compared with the TPR value estimated using cardiac output/heart rate before and after phenylephrine administration. The astronauts in the post-flight presyncopal group had lower pre-flight TPR changes (1.66 times) than those in the non-presyncopal group (2.15 times). The trend in TPR changes calculated with our algorithm agreed with the TPR trend calculated using measured cardiac output in the previous study. Further data collection and algorithm refinement are needed for pre-flight detection of OI and monitoring of continuous TPR by analysis of peripheral arterial blood pressure. 相似文献
227.
This paper describes a novel procedure for determing the accuracy of hyperbolic multilateration systems. Basically, the procedure links the conventional accuracy measures (e. g., GDOP) to the moments and products of inertia of a mass configuration that is easily derived from the system geometry. Thus, the problem of determining accuracy measures is reduced to that of calculating simple moments and products of inertia. The insight provided by the procedure makes it possible to derive a variety of useful approximations for GDOP and other accuracy measures. 相似文献
228.
J T Lett A B Cox D S Bergtold A C Lee J E Pickering 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(10):251-256
Optic tissues in groups of New Zealand white rabbits were irradiated locally at different stages throughout the median life span of the species with a single dose (9 Gy) of 425 MeV/amu Ne ions (LET infinity approximately 30 keV/micrometer) and then inspected routinely for the progression of radiation cataracts. The level of early cataracts was found to be highest in the youngest group of animals irradiated (8 weeks old), but both the onset of late cataracts and loss of vision occurred earlier when animals were irradiated during the second half of the median life span. This age response can have serious implications in terms of space radiation hazards to man. Rhesus monkeys that had been subjected to whole-body skin irradiation (2.8 and 5.6 Gy) by 32 MeV protons (range in tissue approximately 1 cm) some twenty years previously were analysed for radiation damage by the propagation of skin fibroblasts in primary cultures. Such propagation from skin biopsies in MEM-alpha medium (serial cultivation) or in supplemented Ham's F-10 medium (cultivation without dilution) revealed late damage in the stem (precursor) cells of the skins of the animals. The proton fluxes employed in this experiment are representative of those occurring in major solar flares. 相似文献
229.
Chin S.A. Chen D.Y. Lee F.C. 《IEEE transactions on aerospace and electronic systems》1983,(2):203-214
Three sets of design graphs and equations are developed to facilitate design of the energy-storage inductors for dc-to-dc converters. Using the design graphs, a quick estimate of the inductor minimum weight, the transistor peak current, and the inductor power loss can be obtained. Tradeoff studies can be conveniently conducted using these graphs. The effects of duty cycle controllers, constant frequency and constant tON, on the optimal selection of the energystorage inductors are assessed. 相似文献
230.
Yuan Yu Lee F.C.Y. Triner J.E. 《IEEE transactions on aerospace and electronic systems》1979,(3):344-355
Utilizing the demonstrated capability of nonlinear programming algorithms, a practical design optimization approach for power converters is established which allows conception of a design to meet all power-circuit performance requirements and concurrently optimize a defined quantity such as weight or losses. In addition to facilitating a costeffective design, the computer-aided approach provides a means to readily assess 1) the weight-efficiency tradeoff, 2) impacts of converter requirements and component characteristics on a given design, and 3) optimum powersystem configurations. 相似文献