The development of a conformal nanotube process is enabling for many applications in solar physics and space astrophysics (e.g., direct detection and imaging of exoplanets). Coronagraphs are key heliophysics instruments because they image coronal mass ejections (CMEs), which are the most energetic phenomena on the Sun. CMEs have wide-ranging impact on the heliosphere, from interplanetary spacecraft to Earthorbiting satellites, communications, and astronaut safety; in short, they are major drivers of space weather. In a typical space-based coronagraph, an external occulter blocks light from the disk of the Sun so that the corona (about a million times dimmer) can be imaged. The occulter must suppress both diffracted light and stray light.

Modelling and Evaluation of Aircraft Contrails for 4-Dimensional Trajectory Optimisation

2015-01-253809/15/2015

Contrails and aircraft-induced cirrus clouds are reputed being the largest components of aviation-induced global warming, even greater than carbon dioxide (CO2) exhaust emissions by aircraft. This article presents a contrail model algorithm specifically developed to be integrated within a multi-objective flight trajectory optimization software framework. The purpose of the algorithm is to supply to the optimizer a measure of the estimated radiative forcing from the contrails generated by the aircraft while flying a specific trajectory. In order to determine the precise measure, a comprehensive model is employed exploiting the Schmidt-Appleman criterion and ice-supersaturation regions. Additional parameters such as the solar zenith angle, contrail lifetime and spread are also considered. The optimization of flight trajectories encompassing such contrail model allows for selective avoidance of the positive radiative forcing conditions, such as only avoiding persistent contrails, or

Lim, Yixiang, Gardi, Alessandro, Sabatini, Roberto

Flight Proving a Heliophysics Soft X-Ray Imager

TBMG-22394

07/01/2015

The interaction between the solar wind and the Earth’s magneto - sphere results in “space weather.” To determine the true nature of the solar wind-magnetosphere interaction, scientists require global measurements of processes occurring at the bow shock, in the magnetosheath, and at the magnetopause. Such observations can only be obtained from imaging this interaction globally. This will produce a paradigm shift similar to how satellite imaging revolutionized terrestrial weather forecasting.

Autonomous Guidance Algorithm to Auto-Pilot Spacecraft in the Vicinity of Primitive Celestial Bodies

TBMG-22409

07/01/2015

The dynamics in the vicinity of small bodies are highly nonlinear. Trajectory design in small-body environments requires accurate gravity and solar radiation pressure models to guarantee the satisfaction of spacecraft operational constraints such as thruster silent times, state, and control constraints. The G-PROX guidance algorithm generates fuel-optimal trajectories in the vicinity of asteroids and small bodies. The non-convexity in the control constraints is handled with the lossless convexification technique, which is a convex relaxation of the control constraints. G-PROX uses sequential convex programming and solves a convergent sequence of convex optimization problems generated via sequential linearization of both the dynamics and control bounds, synergistically combined with lossless convexification. The sequence of convex optimization problems converges to a locally optimal solution of the original nonlinear non-convex problem.

High-Energy Instrumentation for Small Satellite Platforms

TBMG-2199205/01/2015

Given the increased availability of small satellite opportunities either through CubeSats or the Air Force’s University Nanosat program, and the limited availability of larger platforms, it is challenging to develop new instrumentation that not only fits within the envelope of small satellites, but also addresses the diverse science applications available in low Earth orbit (LEO). While small-platform instrumentation is limited in sensitivity, the ability to populate LEO with a fleet of instruments opens new science objectives not available with larger standalone payloads. Furthermore, coordinated observations of a variety of radiation species that either enter LEO from the Sun or heliosphere directly, or that reside within the radiation belts themselves, are necessary to fully reach closure on complex processes that govern particle acceleration and transport.

Neutron Spectrometer for Inner Radiation Belt Studies

TBMG-2199105/01/2015

The Earth’s magnetosphere offers a wealth of information on particle dynamics, acceleration, and trapping. Fast neutrons, produced in the Earth’s atmosphere by the impact of galactic cosmic rays (GCRs) and solar energetic particles (SEPs), are an important but poorly measured component of the radiation environment in the inner magnetosphere. Cosmic ray albedo neutron decay (CRAND), whereby atmospheric neutrons beta-decay into protons and electrons, is a significant source of energetic protons in the inner radiation belt. Current models of the inner proton belt rely heavily on Monte Carlo simulations for the CRAND component, validated primarily by a handful of single-point balloon measurements from the 1970s.

Space Weather Database of Notifications, Knowledge, Information — DONKI

TBMG-22025

05/01/2015

SW DONKI is a comprehensive Web application for space weather forecasters, scientists, and the general space weather community. It serves as an archive for space weather activities including solar flares, coronal mass ejections (CMEs), solar energetic particles, and geomagnetic storms. An innovative feature of the system is the ability to generate, modify, and store complex linkages between space weather events — creating a comprehensive network of relationships between activities, and identifying potential cause-and-effect paradigms for each space weather event. SW DONKI also provides public access to all human-generated event analysis and notifications produced by the Space Weather Research Center (SWRC) forecasting team at CCMC (Community Coordinated Modeling Center).

Sleeper Cab Climate Control Load Reduction for Long-Haul Truck Rest Period Idling

2015-01-035104/14/2015

Annual fuel use for long-haul truck rest period idling is estimated at 667 million gallons in the United States. The U.S. Department of Energy's National Renewable Energy Laboratory's CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck climate control systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In order for candidate idle reduction technologies to be implemented at the original equipment manufacturer and fleet level, their effectiveness must be quantified. To address this need, a number of promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads. For this study, load reduction strategies were grouped into the focus

Lustbader, Jason A., Kreutzer, Cory, Adelman, Steven, Yeakel, Skip, Zehme, John

One-Dimensional Solar Heat Load Simulation Model for a Parked Car

2015-01-035604/14/2015

Passenger comfort and safety are major drivers in a typical automotive design and optimization cycle. Addressing thermal comfort requirements and the thermal management of the passenger cabin within a car, which involves accurate prediction of the temperature of the cabin interior space and the various aggregates that are present in a cabin, has become an area of active research. Traditionally, these have been done using experiments or detailed three-dimensional Computational Fluid Dynamics (CFD) analysis, which are both expensive and time-consuming. To alleviate this, recent approaches have been to use one-dimensional system-level simulation techniques with a goal to shorten the design cycle time and reduce costs. This paper describes the use of Modelica language to develop a one-dimensional mathematical model using Modelica language for automotive cabin thermal assessment when the car is subjected to solar heat loading. The developed model has the capability to predict the thermal

Patil, Aniket, Radle, Manoj, Shome, Biswadip, Ramachandran, Sankar

Climate Control Load Reduction Strategies for Electric Drive Vehicles in Warm Weather

2015-01-035504/14/2015

Passenger compartment climate control is one of the largest auxiliary loads on a vehicle. Like conventional vehicles, electric vehicles (EVs) require climate control to maintain occupant comfort and safety, but cabin heating and air conditioning have a negative impact on driving range for all-electric vehicles. Range reduction caused by climate control and other factors is a barrier to widespread adoption of EVs. Reducing the thermal loads on the climate control system will extend driving range, thereby reducing consumer range anxiety and increasing the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have investigated strategies for vehicle climate control load reduction, with special attention toward EVs. Outdoor vehicle thermal testing was conducted on two 2012 Ford Focus Electric vehicles to evaluate thermal management strategies for warm weather, including solar load reduction and cabin pre-ventilation. An advanced thermal test manikin was used to

Jeffers, Matthew A., Chaney, Larry, Rugh, John P.

Solar Powered Vehicle Parking Ventilation System Pre-Cooling Analysis

2015-01-036704/14/2015

The cabin air temperature increases quickly and can reach 80°C when the vehicle parks in the summer sunlight which has the bad influence on the occupants entering comfort. Some luxury vehicles, like Audi A8[1], reduce the internal temperature through operating air-condition in advance or using on-board battery to drive the cabin ventilator, which requires relatively complex control system and limits the system's operating time because of energy consumption. This research adopts the solar wing as the ventilation power supply and accomplishes the cabin real-time heat rejection by achieving the steady air circulation for both inside and outside environment. First, the static thermal transfer model of the crew cabin is established. Then, on the basis of the parameters of the prototype ventilation pipe, the ventilation model for the outside circulation is built. After that, the parameters of the solar wing are determined according to the control target of the cabin internal air temperature

Hu, Zhiqiang, Tan, Gangfeng, Li, Zhilei, Xu, Haobo, Huang, Wenhui, Ye, Yifan

The Energy Management for Solar Powered Vehicle Parking Ventilation System

2015-01-014904/14/2015

In summer, when vehicle parks in direct sunlight, the closed cabin temperature would rise sharply, which affects the occupants step-in-car comfort Solar powered vehicle parking ventilation system adopts the solar energy to drive the original ventilator. Thus, the cabin temperature could be dramatically decreased and the riding comfort could be also improved. This research analyzed the modified crew cabin thermal transfer model. Then the performance of the solar powered ventilation system is analyzed and optimized combined with the power supply characteristics of the photovoltaic element. The storage and reuse of the solar power is achieved on condition that the cabin temperature could be steadily controlled. The research shows that, the internal temperature is mainly affected by the solar radiation intensity and the environment temperature. Within the environmental conditions area where the environmental temperature is set from 30°C to 45°C and the solar radiation intensity is set from

Wang, Can, Tan, Gangfeng, Guo, Xuexun, Tian, Zhewen, Tian, Zhanwei, Li, Jiafan

Fast and Efficient Detection of Shading of the Objects

2015-01-037104/14/2015

The human thermal comfort, which has been a subject of extensive research, is a principal objective of the automotive climate control system. Applying the results of research studies to the practical problems require quantitative information of the thermal environment in the passenger compartment of a vehicle. The exposure to solar radiation is known to alter the thermal environment in the passenger compartment. A photovoltaic-cell based sensor is commonly used in the automotive climate control system to measure the solar radiation exposure of the passenger compartment of a vehicle. The erroneous information from a sensor however can cause thermal discomfort to the occupants. The erroneous measurement can be due to physical or environmental parameters. Shading of a solar sensor due to the opaque vehicle body elements is one such environmental parameter that is known to give incorrect measurement. The fundamental geometric principles of the intersection of a line segment and a plane can

Kakade, Rupesh Sonu, Mer, Prashant

Diagnostics-in-a-Suitcase Rapidly Detects Ebola

TBMG-21353

01/12/2015

Scientists in field laboratories who diagnose and deal with Ebola infections often work under challenging conditions. Researchers at the German Primate Center have developed Diagnostics-in-a-Suitcase, which contains all reagents and equipment to detect the Ebola virus within 15 minutes at point-of-need. Moreover, the mobile suitcase laboratory will be operated by an integrated solar panel and a power pack.

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