Compared to airports in other countries, airports in Japan are narrow and it is difficult to secure a suitable site for reference stations of Ground-Based Augmentation System (GBAS). Even in Europe and the U.S., where there are large enough sites, the impact of aircraft passing overhead has been reported. First, the authors examined the impact of shadowing the GPS signals on GBAS. Next, based on the analysis of data acquired by the GBAS for evaluation purposes at New Chitose Airport, the authors evaluated the impact of GPS signal shadowing by landing aircraft on GBAS. Furthermore, based on the results of computer simulations, we proposed a method to reduce the impact of GPS signal shadowing by landing aircraft, and discussed the impact on the availability of GBAS.

The WADGPS (wide area differential GPS) is affected by site displacements with the dominant component of solid earth tide within up to 30cm, through the process of satellite orbit determination. The WADGPS based on the recent standards, L5 SBAS, augmenting DFMC (Dual-Frequency Multi-Constellation) environment has an option to consider this effect because of its accuracy much better than the legacy L1 SBAS and comparable to the magnitude of the effects. This paper gives some formulation of site displacement effects on WADGPS and proposes a cancellation method. It is confirmed that proposed method cancels the effects with 1 to 2cm accuracy for the configuration of Japanese MSAS.

As human activities expand into space, establishing a sustainable circular system is crucial rather than relying on resupplies from Earth. While system mass, including the amount of resupplies, has traditionally been a key factor in design optimization, this study proposes the use of ``exergy,'' which represents effective energy and incorporates the concept of entropy, as a new design metric for evaluating material and energy circulation. The objective of this study is to compare multiple Environmental Control and Life Support System (ECLSS) approaches, from the conventional physiochemical International Space Station (ISS) method to advanced bioregenerative concepts such as photosynthesis and waste reclamation. To further reflect the cost of delivery from Earth, the concept of ``Modified Exergy'' is introduced, incorporating gravitational potential and kinetic energy into the exergy framework. Also, location factors are applied for deep space platforms.

Jovian entry probes experience extremely severe aerodynamic heating environment due to its 47km/s entry velocity into a hydrogen–helium atmosphere. During the Galileo development program, thermal protection system (TPS) was evaluated using hydrogen arc-jet heating facility and laser heating facilities; however, these facilities are no longer available today. To address this issue, we focused on the similarity between Jovian entry probe and the divertor of fusion reactors and established a TPS recession rate measurement method using high heat flux test facility (JEBIS) owned by the National Institutes for Quantum Science and Technology (QST). As a result, we successfully obtained fast recession behavior of carbon-phenolic material under approximately 200MW/m² heat flux, corresponding to the Jovian entry environment. The evaluation results showed good agreement with those from NASA's hydrogen arc-jet and laser heating methods, demonstrating the applicability of the electron beam method to assessments of TPS performance for Jupiter entry probes.