因特网实时动态GPS"智能桥梁"的设计与实施

介绍了基于因特网的实时动态GPS在大型结构变形监测中应用的原型系统的概念与设计.该系统包括参考基站、监测站、控制中心和用户4部分.文中采用了模拟桥梁变形的仿真平台验证该原型系统.实验结果表明:在10 Hz的采样率下,该系统的数据传输时间延迟可以忽略不计, 并可达到毫米级的三维定位精度.     

你是智者吗？

还在念小学的时候,老师就教过我们关于“多元智能理论”的内容,那是由一位名叫霍华德·加德纳的博士提出来的。他是哈佛大学的首席讲座教授,获得过各种各样的奖项;他还是麦克阿瑟奖获得者,拥有四大洲二十九个大学的荣誉学位。     

W.W.W. MOON? The why, what and when of a permanent manned lunar colony

Several reasons for going back to the Moon are listed: scientific study of our natural satellite, Earth and in general the Solar System; exploitation of the resources of Outer Space; geopolitical considerations that made Apollo possible and are still valid in the long term; advancement of manned spaceflight, as robot-based exploration is time-wise inefficient and politically negligible. Technological, organisational and legal challenges are then outlined. After a discussion of human physiology, building materials and transportation of people and goods, an underground polar location is proposed as settlement site, either within kilometre-size lava tubes or man-made caves. An analysis of spaceflight history is conducted to determine a target date for returning to the Moon to stay. In the absence of political or commercial competition, experience indicates the last decades of the XXI century. To shorten this timescale, it is recommended to focus on accomplishing the task of establishing a reliable lunar travel and settlement system, rather than developing new technologies: simplifying the goals of each single step forward (as was the case of the Clementine mission) and concentrating on production-ready (or almost-ready) equipment (compare the ill-fated X-33 to the dependable Soyuz capsules).     

The effect of hypokinesia on lipid metabolism in adipose tissue

The increase of nonesterified fatty acid (NEFA) concentration in plasma was observed in rats subjected to hypokinesia for 1-60 days. In the period of recovery (7 and 21 days after 60 days immobilization) the content of NEFA returned to control values. The increase of fatty acid release from adipose tissue was observed in hypokinetic rats, however the stimulation of lipolysis by norepinephrine was lower in rats exposed to hypokinesis. The decrease of the binding capacity and a diminished number of beta-adrenergic receptors were found in animals after hypokinesia. The augmentation of the incorporation of glucose into lipids and the marked increase in the stimulation of lipogenesis by insulin were found in adipose tissue of rats subjected to long-term hypokinesia. These results showed an important effect of hypokinesia on lipid mobilization, on lipogenesis and on the processes of hormone regulation in adipose tissue.     

新技术将如何改变MRO领域

<正>未来可能应用于MRO领域的新技术有很多,有的是受上游产业影响而发展的,有的是新技术的直接应用,如复合材料修理、增材制造、数字孪生、预测性维修、增强现实、自动化、机器人等等,但这些技术真正应用于MRO领域后会是何种程度,应用中还存在哪些障碍,亦或是其他新的商业模式还会催生出哪些新的技术,这些都应该提前思考。     

太空科技 反哺希望 ISS最具影响力的十项研究成果大盘点

在十项研究成果中,排名倒数第一的是,通过饮食和锻炼防止太空中的骨质丢失,这始于早期对国际空间站航天员骨质丢失方面的研究。据空间站历史记载,航天员的骨密度丧失量约为15％／月,这相当于女性绝经后全年的骨质丢失量。为此,科学家们开始着眼于乘员的日常饮食和锻炼,并配备了一些锻炼器械。结论是,一套持续的高强度锻炼和适量的维生素D与热量的正确结合,是骨健康的关键。该成果有助于了解骨在人体内的形成和维持机制,因而引人注目。     

In vitro edible muscle protein production system (MPPS): stage 1, fish

The working efficiency and state-of-mind of a Space vehicle crew on long-term missions is dependent on the suitability of living conditions including food. Our purpose was to establish the feasibility of an in vitro muscle protein production system (MPPS) for the fabrication of surrogate muscle protein constructs as food products for Space travelers. In the experimental treatments, we cultivated the adult dorsal abdominal skeletal muscle mass of Carassius (Gold fish). An ATCC fish fibroblast cell line was used for tissue engineering investigations. No antibiotics were used during any phase of the research. Our four treatments produced these results: a low contamination rate, self-healing, cell proliferation, a tissue engineered construct of non-homologous co-cultured cells with explants, an increase in tissue size in homologous co-cultures of explants with crude cell mixtures, maintenance of explants in media containing fetal bovine serum substitutes, and harvested explants which resembled fresh fish filets.

We feel that not only have we pointed the way to an innovative, viable means of supplying safe, healthy, nutritious food to Space voyagers on long journeys, but our research also points the way to means of alleviating food supply and safety problems in both the public and private sectors worldwide.     

Changes in mood status and neurotic levels during a 20-day bed rest

This study evaluated changes of mood status and depressive and neurotic levels in nine young male subjects during a 20-day 6 degrees head-down tilting bed rest and examined whether exercise training modified these changes. Participants were asked to complete psychometrical inventories on before, during, and after the bed rest experiment. Depressive and neurotic levels were enhanced during bed rest period according to the Japanese version of Zung's Self-rating Depression Scale and the Japanese version of the General Health Questionnaire. Mood state "vigor" was impaired and "confusion" was increased during bed rest and recumbent control periods compared to pre-bed rest and ambulatory control periods according to the Japanese version of Profiles of Mood State, whereas the mood "tension-anxiety", "depression-dejection", "anger-hostility" and "fatigue" were relatively stable during experiment. Isometric exercise training did not modify these results. Microgravity, along with confinement to bed and isolation from familiar environments, induced impairment of mental status.     

边界层对可调节进气道性能的影响

给出了马赫数2~6、单位雷诺数(0.8~6.0)×107/m时下吹式风洞中可调节三维进气道的试验研究结果.研究了前缘前掠和后掠方案以及进气道入口前边界层的影响.测量了内流道内的压力分布、质量流量和总压恢复系数;确定了进气道启动与马赫数和流动工况的关系.研究结果表明:边界层对流场结构和模型进气道的性能有着决定性影响,相对简单的进气道调节方案可以增大其稳定运行范围.