Passiv damping on spacecraft sandwich panels

For reusable and expendable launch vehicles as well as for other spacecraft structural vibration loads are safety critical design drivers impacting mass and lifetime. Here, the improvement of reliability and safety, the reduction of mass, the extension of service life, as well as the reduction of cost for manufacturing are desired. Spacecraft structural design in general is a compromise between lightweight design and robustness with regard to dynamic loads. The structural stresses and strains due to displacements caused by dynamic loads can be reduced by mechanical damping based on passive or active measures. Passive damping systems can be relatively simple and yet are capable of suppressing a wide range of mechanical vibrations. Concepts are low priced in development, manufacturing and application as well as maintenancefree. Compared to active damping measures passive elements do not require electronics, control algorithms, power, actuators, sensors as well as complex maintenance. Moreover, a reliable application of active dampers for higher temperatures and short response times (e. g. re-entry environment) is questionable. The physical effect of passive dampers is based on the dissipation of load induced energy. Recent activities performed by OHB have shown the function of a passive friction-damping device for a vertical tail model of the German X-vehicle PHÖNIX but also for general sandwich structures. The present paper shows brand new results from a corresponding ESA-funded activity where passive damping elements are placed between the face sheets of large spacecraft relevant composite sandwich panels to demonstrate dynamic load reduction in vibration experiments on a shaker. Several passive damping measures are investigated and compared

Orbital-Hub DLR Vision 2025

In line with the space strategy of the German Government, ISS follow-on activities should comprise clear scientific objectives and key technological competences (e.g. robotic, internal and external structures, module/facility and experiment operations, interface systems (ATV)). In this way, DLR started to investigate future options by evaluating various LEO infrastructure concepts including opportunities for national realisation or international cooperation. A corresponding list of options can be found below. DLR scientists from various disciplines were asked to assess the usability of these options and design payloads based on their Mir and ISS experience and with respect to future scientific fundamental and technological research questions

TOWARDS A MATURITY MODEL: BED MANAGEMENT CAPABILITIES IN HOSPITALS

As instrumental healthcare institutions providing high quality patient care, hospitals are currently facing multiple challenges ranging from pressure to reduce costs to a rapidly increasing elderly population. From a process perspective hospitals feature support and management processes, which enable the core process of providing patient care. One of the most crucial process areas – bed management – refers primarily to logistics processes related to the physical beds in hospitals. However, these are closely intertwined with diverse management and support processes (e.g., occupancy management). In order to conceptualize bed management as a process area from a holistic perspective, we develop a capability framework based on a thorough literature review as well as subsequent evaluation of the framework’s relevance, completeness, and practical applicability in two German hospitals. The capability framework includes 30 capabilities grouped into six overarching capability areas. It suggests that efficient and effective bed management is predicated on pooling organizational resources from various organizational units and functional areas. Our work serves as a foundation for the development of a respective maturity model. It enables practitioners to systematically manage capabilities related to bed management and supports them in deriving roadmaps, conducting fit/gap analyses, and prioritizing topics, while accounting for the hospital-specific context

Teaching Space Master Concurrent Engineering

Since 2014 the University of Bremen (Germany) offers the Master of Space Engineering (SpE), a master course geared towards international engineering students. For the past years, DLR has supported the program through the compulsory module Space Systems Engineering and Concurrent Engineering, held at the Concurrent Engineering Facility (CEF) at the Institute of Space Systems. After classical theory lectures on Project Management, Systems Engineering, Concurrent Engineering as well as on the relevant Space Subsystem Domains the students are introduced to CE in practice by performing a four-day simulation of a Phase 0/A CE study. This paper describes the experiences and advantages, as well as the difficulties, of teaching Concurrent Design/Engineering at University within a Space Master course

Service Section Design of the EDEN ISS Project

The international EDEN ISS project aims to investigate and validate techniques for plant cultivation in future bioregenerative life support systems. To this end the EDEN ISS project partners aim to design and build the Mobile Test Facility, which consists of two modified 20 foot shipping containers. One of these shipping containers is designated the Service Section and houses the bulk of the subsystem components, such as the Air Management System and Nutrient Delivery System, as well as a rack-sized plant cultivation system, which uses a standard International Space Station payload form factor. The subsystems within the Service Section ensure that the approximately 12.5 m² of cultivation area in the second container, the Future Exploration Greenhouse, have the proper environmental conditions, nutrients and illumination for optimal crop growth. The EDEN ISS project concluded its main design phase with a Critical Design Review in March 2016, thereafter proceeded into the hardware development and procurement phase of the project. This paper describes the final design of the Service Section at the start of the assembly, integration and testing phase, which will run until the complete Mobile Test Facility is shipped to Antarctica, where it arrives in December 2017, for a 12 month space analogue mission

The preliminary design of the EDEN ISS Mobile Test Facility - An Antarctic greenhouse

EDEN ISS is a European project to investigate cultivation techniques of plants in space for future bio-regenerative life support systems. The technologies will be tested in a laboratory environment as well as at the highly-isolated German Antarctic Neumayer Station III. A small and mobile container-sized test facility will be built in order to provide realistic mass flow relationships. This paper provides a summary of the activities performed in the early design phase of the project. The design phase started with the kick-off meeting in March 2015 and focused on the requirements definition and design of the greenhouse. The EDEN ISS partners met for a design workshop from September 7th to September 18th, 2015 in the Concurrent Engineering Facility of DLR’s Institute of Space Systems in Bremen, Germany. The purpose of the workshop was the generation of a preliminary design for the Mobile Test Facility. The Mobile Test Facility will be built later in the project and used to conduct an over one year long experiment campaign beginning in December 2017 in Antarctica. During the two week workshop, the consortium members worked on their respective subsystems and on how their systems can be integrated in the overall greenhouse. The design of each subsystem was greatly improved. System budgets (e.g. mass, power) were calculated, engineering drawings created and estimates with respect to inputs and outputs made. A very important step was the consolidation of the system and subsystem requirements. This paper summarizes the results of the design work-shop and describes the preliminary design of the EDEN ISS Mobile Test Facility

Introducing EDEN ISS - A European project on advancing plant cultivation technologies and operations

Plant cultivation in large-scale closed environments is challenging and several key technologies necessary for space-based plant production are not yet space-qualified or remain in early stages of development. The EDEN ISS project foresees development and demonstration of higher plant cultivation technologies, suitable for future deployment on the International Space Station and from a long-term perspective, within Moon and Mars habitats. The EDEN ISS consortium will design and test essential plant cultivation technologies using an International Standard Payload Rack form factor cultivation system for potential testing on-board the International Space Station. Furthermore, a Future Exploration Greenhouse will be designed with respect to future planetary bio-regenerative life support system deployments. The technologies will be tested in a laboratory environment as well as at the highly-isolated German Antarctic Neumayer Station III. A small and mobile container-sized test facility will be built in order to provide realistic mass flow relationships. In addition to technology development and validation, food safety and plant handling procedures will be developed. This paper describes the goals and objectives of EDEN ISS and the different project phases and milestones. Furthermore, the project consortium will be introduced and the role of each partner within the project is explained

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362