Crew Transportation System Design Reference Missions

Contains summaries of potential design reference mission goals for systems to transport humans to andfrom low Earth orbit (LEO) for the Commercial Crew Program. The purpose of this document is to describe Design Reference Missions (DRMs) representative of the end-to-end Crew Transportation System (CTS) framework envisioned to successfully execute commercial crew transportation to orbital destinations. The initial CTS architecture will likely be optimized to support NASA crew and NASA-sponsored crew rotation missions to the ISS, but consideration may be given in this design phase to allow for modifications in order to accomplish other commercial missions in the future. With the exception of NASAs mission to the ISS, the remaining commercial DRMs are notional. Any decision to design or scar the CTS for these additional non-NASA missions is completely up to the Commercial Provider. As NASAs mission needs evolve over time, this document will be periodically updated to reflect those needs

Crew Transportation Operations Standards

The Crew Transportation Operations Standards contains descriptions of ground and flight operations processes and specifications and the criteria which will be used to evaluate the acceptability of Commercial Providers' proposed processes and specifications

The conundrum of conservation agriculture and livelihoods in Southern Africa

Low crop productivity, food insecurity, hunger and malnutrition; inadequate farming knowledge and skills, implements and inputs are characteristic of smallholder agriculture in Southern Africa. Many researchers argue that conservation agriculture can guarantee higher crop productivity, food security, improved livelihoods and environmental protection, better than the unsustainable traditional systems of slash and burn practices. In this paper, we present the results of a meta-analysis of over 40 academic publications to review conservation agriculture’s role in influencing desired livelihood outcomes in Southern Africa. We conclude that the effectiveness of conservation agriculture towards better livelihood outcomes in Southern Africa remains debatable, especially when supportive government policies are lacking

NASA's Commercial Crew Program, The Next Step in U.S. Space Transportation

The Commercial Crew Program (CCP) is leading NASA's efforts to develop the next U.S. capability for crew transportation and rescue services to and from the International Space Station (ISS) by the mid-decade timeframe. The outcome of this capability is expected to stimulate and expand the U.S. space transportation industry. NASA is relying on its decades of human space flight experience to certify U.S. crewed vehicles to the ISS and is doing so in a two phase certification approach. NASA Certification will cover all aspects of a crew transportation system, including development, test, evaluation, and verification; program management and control; flight readiness certification; launch, landing, recovery, and mission operations; sustaining engineering and maintenance/upgrades. To ensure NASA crew safety, NASA Certification will validate technical and performance requirements, verify compliance with NASA requirements, validate the crew transportation system operates in appropriate environments, and quantify residual risks

NASA's Commercial Crew Program, the Next Step in U.S. Space Transportation

The Commercial Crew Program (CCP) is leading NASA's efforts to develop the next U.S. capability for crew transportation and rescue services to and from the International Space Station (ISS) by the middecade timeframe. The outcome of this capability is expected to stimulate and expand the U.S. space transportation industry. NASA is relying on its decades of human space flight experience to certify U.S. crewed vehicles to the ISS and is doing so in a two phase certification approach. NASA certification will cover all aspects of a crew transportation system, including: Development, test, evaluation, and verification. Program management and control. Flight readiness certification. Launch, landing, recovery, and mission operations. Sustaining engineering and maintenance/upgrades. To ensure NASA crew safety, NASA certification will validate technical and performance requirements, verify compliance with NASA requirements, validate that the crew transportation system operates in the appropriate environments, and quantify residual risks. The Commercial Crew Program will present progress to date and how it manages safety and reduces risk

Crew Transportation Plan

The National Aeronautics and Space Administration (NASA) Commercial Crew Program (CCP) has been chartered to facilitate the development of a United States (U.S.) commercial crew space transportation capability with the goal of achieving safe, reliable, and cost effective access to and from low Earth orbit (LEO) and the International Space Station (ISS) as soon as possible. Once the capability is matured and is available to the Government and other customers, NASA expects to purchase commercial services to meet its ISS crew rotation and emergency return objectives

Sensitivity of an image plate system in the XUV (60 eV < E < 900 eV)

Phosphor imaging plates (IPs) have been calibrated and proven useful for quantitative x-ray imaging in the 1 to over 1000 keV energy range. In this paper we report on calibration measurements made at XUV energies in the 60 to 900 eV energy range using beamline 6.3.2 at the Advanced Light Source at Lawrence Berkeley National Laboratory. We measured a sensitivity of ~25 plus or minus 15 counts/pJ over the stated energy range which is compatible with the sensitivity of Si photodiodes that are used for time-resolved measurements. Our measurements at 900 eV are consistent with the measurements made by Meadowcroft et al. at ~1 keV.Comment: 7 pages, 2 figure

Village Baseline Study: Site Analysis Report for Kagera Basin – Rakai, Uganda

The village baseline study of Kyengeza village in the CCAFS site Kagera Basin – Rakai in Uganda took place from 4 to 6 July 2011. Study participants are aware that their food security depends on protecting and appropriately managing natural resources. Nonetheless, there is a general decline in the state of natural resources such as rivers, lakes and forests, and the current use of the same resources is not sustainable over time. The main drivers of such changes in the region are population growth and government policies that have privatised forests and other natural areas previously managed by the village, effectively disempowering the community. There are more organisations operating beyond the locality than those operating in the community. The external organisations started delivering food, tools, medicines and other resources in response to HIV/AIDS. Their ability to mobilise resources, however, is undermining self-help capacity within the village, which is not conducive to sustainable rural development. Radio and organisations are the most frequently used sources of information for agricultural decision- making. There is a relatively active information network compared to other CCAFS sites, and a fair amount of consultation with all kinds of sources of information. This may be linked to high levels of uncertainty associated with climate change and food security

A GIS-based assessment of the Byzantine water supply system of Constantinople

Despite the extensive archaeological surveys carried out in the last decades, little attention has been paid to one of the longest water supply systems of ancient times - the Byzantine water infrastructure which fed Constantinople from the mid-late fourth century AD. This work uses modern satellite terrain data and Global Positioning System (GPS) data to assess this system and provide an improved description of its route, total length and gradient profile. Forty-four validated GPS Control Points were correlated with ASTER GDEM V2 digital satellite data and archaeological information in a Geographic Information System (GIS) environment. We concluded that the total length of the water supply system was 426 km, and possibly even 565 km if the fifth-century aqueduct continued in parallel all the way to Constantinople rather than merging with the fourth-century aqueduct. The gradient of the channels varied across their length, being steepest near the spring sources, with a gradient mostly in the region of 5 m/km, and flattest at around 0.4 m/km in the most downstream section nearest the City. This reconstruction of the gradient profile provides valuable insight into the physical characteristics of the system, allowing future study of its hydraulic function.</p