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551.
M. Bamsey A. Berinstain T. Graham P. Neron R. Giroux S. Braham R. Ferl A.-L. Paul M. Dixon 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Arthur Clarke Mars Greenhouse is a unique research facility dedicated to the study of greenhouse engineering and autonomous functionality under extreme operational conditions, in preparation for extraterrestrial biologically-based life support systems. The Arthur Clarke Mars Greenhouse is located at the Haughton Mars Project Research Station on Devon Island in the Canadian High Arctic. The greenhouse has been operational since 2002. Over recent years the greenhouse has served as a controlled environment facility for conducting scientific and operationally relevant plant growth investigations in an extreme environment. Since 2005 the greenhouse has seen the deployment of a refined nutrient control system, an improved imaging system capable of remote assessment of basic plant health parameters, more robust communication and power systems as well as the implementation of a distributed data acquisition system. Though several other Arctic greenhouses exist, the Arthur Clarke Mars Greenhouse is distinct in that the focus is on autonomous operation as opposed to strictly plant production. Remote control and autonomous operational experience has applications both terrestrially in production greenhouses and extraterrestrially where future long duration Moon/Mars missions will utilize biological life support systems to close the air, food and water loops. Minimizing crew time is an important goal for any space-based system. The experience gained through the remote operation of the Arthur Clarke Mars Greenhouse is providing the experience necessary to optimize future plant production systems and minimize crew time requirements. Internal greenhouse environmental data shows that the fall growth season (July–September) provides an average photosynthetic photon flux of 161.09 μmol m−2 s−1 (August) and 76.76 μmol m−2 s−1 (September) with approximately a 24 h photoperiod. The spring growth season provides an average of 327.51 μmol m−2 s−1 (May) and 339.32 μmol m−2 s−1 (June) demonstrating that even at high latitudes adequate light is available for crop growth during 4–5 months of the year. The Canadian Space Agency Development Greenhouse [now operational] serves as a test-bed for evaluating new systems prior to deployment in the Arthur Clarke Mars Greenhouse. This greenhouse is also used as a venue for public outreach relating to biological life support research and its corresponding terrestrial spin-offs. 相似文献
552.
针对目前高校电工电子实验教学中存在的问题,提出了构建多层次实验教学体系、改革实验教学方法和教学手段、完善考核机制等措施,对培养高素质创新型人才有一定的参考价值。 相似文献
553.
本文论述了大学生科技竞赛活动对学校网络工程专业实践教学改革的促进作用。结合网络工程专业的教学实践,提出了重视科技竞赛,促进实践教学改革,提高学生学习兴趣和积极性的一些思路和做法。 相似文献
554.
高辉 《华北航天工业学院学报》2006,16(2):23-25
发展学生的数学能力是数学分析的重要目标之一,怎样才算是恰当地发展学生的数学能力,这与当今普及型的大众化教育目标密切相关。该文概述了数学能力的构成,并以简单的实例阐述了作为数学教师应怎样恰当地把握教学的原则和方法。 相似文献
555.
针对Windows基本操作题的上机考试,提出了将命题、考试与判卷相适应的实现方法。并通过例子,介绍了使题目的文字描述、符号描述和答案符号描述互相对应的描述方法。 相似文献
556.
A.D. Stoev P.V. Stoeva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
This work presents the educational approach of using total solar eclipse occurrences as a scientific process learning aid. The work reviews the basic scientific aims and experiments included in the observational programs “Total solar eclipse 1999 and 2006” (Stoev, A., Kiskinova, N., Muglova, P. et al. Complex observational programme of the Yuri Gagarin Public Astronomical Observatory and STIL, BAS, Stara Zagora Department for the August 11, 1999 total solar eclipse, in: Total Solar Eclipse 1999 – Observational Programmes and Coordination, Proceedings, Recol, Haskovo, pp. 133–137, 1999a (in Bulgarian); Stoeva, P.V., Stoev, A.D., Kostadinov, I.N. et al. Solar Corona and Atmospheric Effects during the March 29, 2006 Total Solar Eclipse, in: 11th International Science Conference SOLAR–Terrestrial Influences, Sofia, November 24–25, pp. 69–72, 2005). 相似文献
557.
赵晓超 《沈阳航空工业学院学报》2008,25(6)
非智力因素在人的成才过程中起重要作用,对培养富有创造性思维的创新人才具有重要的战略意义。体育教学在培养大学生非智力因素中起着积极作用,为此针对体育教师如何结合教学培养学生的非智力因素提出建议。 相似文献
558.
房欢 《长沙航空职业技术学院学报》2013,13(1):36-39
从语言测试学反驳作用的理论出发,笔者分析了公安边防部队广州指挥学校学员公共英语二级模拟考试的成绩及学员反馈调查问卷,从学员的角度来说明公共英语二级考试培训教学的必要性,并探索二级培训的教学方法。 相似文献
559.
S.A. Wolff L.H. Coelho M. Zabrodina E. Brinckmann A.-I. Kittang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Successful growth and development of higher plants in space rely on adequate availability and uptake of water and nutrients, and efficient energy distribution through photosynthesis and gas exchange. In the present review, literature has been reviewed to assemble the relevant knowledge within space plant research for future planetary missions. Focus has been on fractional gravity, space radiation, magnetic fields and ultimately a combined effect of these factors on gas exchange, photosynthesis and transport of water and solutes. 相似文献
560.
陈菊 《中国民航飞行学院学报》2012,(6):65-68
本文采用定性研究和定量研究相结合的方式在两平行班实施实验,探究进行英语周记写作训练能否有效提高大学非英语专业学生的英语写作自信心和写作水平。教学实验数据表明,在经过一学期的英语周记写作训练之后,实验组学生的英语写作自信心和写作水平均明显优于对照组,在统计学上具有显著意义。 相似文献