Science operations planning expertise: A neglected component of mission design

In this paper, Science Operations Planning Expertise (SOPE) is defined as the expertise that is held by people who have the two following qualities. First they have both theoretical and practical experience in operations planning, in general, and in space science operations planning in particular. Second, they can be used, on request and at least, to provide with advice the teams that design and implement science operations systems in order to optimise the performance and productivity of the mission. However, the relevance and use of such SOPE early on during the Mission Design Phase (MDP) is not sufficiently recognised. As a result, science operations planning is often neglected or poorly assessed during the mission definition phases. This can result in mission architectures that are not optimum in terms of cost and scientific returns, particularly for missions that require a significant amount of science operations planning. Consequently, science operations planning difficulties and cost underestimations are often realised only when it is too late to design and implement the most appropriate solutions. In addition, higher costs can potentially reduce both the number of new missions and the chances of existing ones to be extended. Moreover, the quality, and subsequently efficiency, of SOPE can vary greatly. This is why we also believe that the best possible type of SOPE requires a structure similar to the ones of existing bodies of expertise dedicated to the data processing such as the International Planetary Data Alliance (IPDA), the Space Physics Archive Search and Extract (SPASE) or the Planetary Data System (PDS). Indeed, this is the only way of efficiently identifying science operations planning issues and their solutions as well as of keeping track of them in order to apply them to new missions. Therefore, this paper advocates for the need to allocate resources in order to both optimise the use of SOPE early on during the MDP and to perform, at least, a feasibility study of such a more structured SOPE.     

The International DORIS Service (IDS): Toward maturity

DORIS is one of the four space-geodetic techniques participating in the Global Geodetic Observing System (GGOS), particularly to maintain and disseminate the Terrestrial Reference Frame as determined by International Earth rotation and Reference frame Service (IERS). A few years ago, under the umbrella of the International Association of Geodesy, a DORIS International Service (IDS) was created in order to foster international cooperation and to provide new scientific products. This paper addresses the organizational aspects of the IDS and presents some recent DORIS scientific results. It is for the first time that, in preparation of the ITRF2008, seven Analysis Centers (AC’s) contributed to derive long-term time series of DORIS stations positions. These solutions were then combined into a homogeneous time series IDS-2 for which a precision of less than 10 mm was obtained. Orbit comparisons between the various AC’s showed an excellent agreement in the radial component, both for the SPOT satellites (e.g. 0.5–2.1 cm RMS for SPOT-2) and Envisat (0.9–2.1 cm RMS), using different software packages, models, corrections and analysis strategies. There is now a wide international participation within IDS that should lead to future improvements in DORIS analysis strategies and DORIS-derived geodetic products.     

A straw-soil co-composting and evaluation for plant substrate in BLSS

Material closure is important for the establishment of Bioregenerative Life Support System, and many studies have focused on transforming candidate plant residues into plant culture medium. For the limitations of using wheat straw compost as substrate for plant cultivation, a straw-soil co-composting technique was studied. The changes of pH, C/N value, germination index, cellulose, lignin and so on were monitored during the co-composting process. The maturity was evaluated by the C/N value and the germination index. The result showed that after 45 days’ fermentation, the straw-soil final co-compost with inoculation (T1) became mature, while the co-compost without inoculation (T0) was not mature. In the plant culture test, the T1 substrate could satisfy the needs for lettuce’s growth, and the edible biomass yield of lettuce averaged 74.42 g pot⁻¹ at harvest. But the lettuces in T0 substrate showed stress symptoms and have not completed the growth cycle. Moreover, the results of nitrogen (N) transformation experiment showed that about 10.0% and 3.1% N were lost during the T1 co-composting and plant cultivation, respectively, 23.5% N was absorbed by lettuce, and 63.4% N remained in the T1 substrate after cultivation.     

在制品管理中条码技术的应用

针对面向订单的单件、小批量生产制造企业,设计了一套条码数据采集系统,分析了主要运作流程和功能模块.在在制品的管理中提出了基于不同级别的工件生产状态定义,并给出了相应的加工、检验判定准则.经实际使用证明条码技术运用于工业现场是可行的.     

刀具库房信息化管理实践及展望

本文针对科研生产混合型的数控车间刀具库房管理过程,以流程优化、完善制度和信息化管理为重点,总结归纳出刀具库房信息化管理的方法和手段,并以中航工业北京航空制造工程研究所数控某刀具库房信息化系统建设为实例,说明了刀具库房管理实施方法及过程。     

飞机纵向驾驶员诱发振荡灵敏度分析

采用系统灵敏度理论，以修正的带宽准则，增益和相位裕度准则以及Ｎｅａｌ－ｓｍｉｔｈ准则等飞机纵向驾驶员诱发振荡（ＰＩＯ）预测准则作为系统指标，建立了参数变化对诱发振荡预测指标影响的灵敏度公式，以ＪＪ７飞机为例，给出了飞机，操纵系统及驾驶员参数上述指标影响的灵敏度，根据计算结果进行了ＰＩＯ参数敏度预测分析，同时与数值仿真结果进行了对比分析。     

小波技术在组合导航系统故障诊断中的应用

针对组合导航系统中存在的故障类型和特点，提出一种新的基于信号处理的故障检测方法。该方法利用小波分析技术对含有故障信息的系统信号进行分析处理，并将此方法应用于SINS／GPS组合导航系统。仿真结果分析表明，小波分析技术能很好地及时检测出组合导航系统的硬故障，且更加简便灵活，从而可以将小波分析技术应用于组合导航系统的故障检测。     

对建立工业快速动员体系的探讨

本文介绍了美国快速动员体系的基本情况，对建立我国的快速动员体系提出了几点建议。     

Innovation and change? The evolution of Europe's small satellite manufacturers

Since the 1980s a trend has emerged to contain the cost of space missions, which has favored trials in the construction and launch of small satellites. This effort has considerably reduced the cost of the satellites because the construction process uses both traditional components and important technological innovations. There have also been market openings for small satellites, both within the telecommunication sector and for scientific missions and those related to Earth observation. This paper contains the results of a survey of the largest manufacturers of small satellites in Europe and investigates how far (if at all) they have changed the structure of the European space industry. It finds that, through the acquisition of small satellite manufacturers, traditional large companies operating in the field of space in Europe have secured for themselves important technological innovations and market opportunities, while maintaining their oligopolistic position.     

Crew autonomy for deep space exploration: Lessons from the Antarctic Search for Meteorites

Future piloted missions to explore asteroids, Mars, and other targets beyond the Moon will experience strict limitations on communication between vehicles in space and control centers on Earth. These limitations will require crews to operate with greater autonomy than any past space mission has demonstrated. The Antarctic Search for Meteorites (ANSMET) project, which regularly sends small teams of researchers to remote parts of the southern continent, resembles a space mission in many ways but does not rely upon a control center. It provides a useful crew autonomy model for planners of future deep space exploration missions. In contrast to current space missions, ANSMET gives the crew the authority to adjust competing work priorities, task assignments, and daily schedules; allows the crew to be the primary monitor of mission progress; demands greater crew accountability for operational errors; requires the crew to make the most of limited communication bandwidth; adopts systems designed for simple operation and failure recovery; and grants the crew a leading role in the selection and stowage of their equipment.