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The purpose of a power subsystem is to ensure reliable delivery of electrical power compatible with all loads under all foreseeable operational states and environments, during all mission phases, and over the intended design life of the loads and of the space vehicle and the power subsystem is unarguably the most critical subsystem on a satellite. Therefore, reliability, efficiency, autonomy, redundancy and size features become critical issues in design and implementation of a satellite power system. Moreover, these parameters associated with the power subsystem usually determine the lifetime of a satellite. This paper describes the design details with redundancy concept, autonomous operation, single point free architecture and sizing of RASAT flight model power subsystem. Technical description and the qualification level of each power system module are also presented. For the battery charge regulator, the parallel operation and an effective MPPT algorithm will be presented in detail. Moreover, the power productionconsumption analysis and power system sizing will also be included for different scenarios.

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European Space Agency (ESA) has addressed the key points like higher power demand and system efficiency, system reusability, adaptability and flexibility, decrease in system mass, size and cost, increase in modularity and standardization for the next generation (NG) power systems on future missions at 8 th Space Power Conference. Since the purpose of a power distribution module is to ensure reliable delivery of electrical power and prevent failure propagation, under all foreseeable conditions, during all mission phases, reliability and redundancy become critical issues in design. This paper describes UYGAR, which is the power distribution module designed in TUBITAK UZAY for Low Earth Orbit (LEO), Geostationary Earth Orbit (GEO) and Science Missions with its single point failure free, 100 kRad radiation tolerant and internally redundant electronic design while considering the key points addressed by ESA and the experiences gained in TUBITAK UZAY's previous satellite missions RASAT and GÖKTÜRK-2. This paper describes the high reliable, radiation tolerant, flexible, and unique design details compatible with ECSS-E-ST-20C and AIAA-S-122-2007 of NG power distribution module, UYGAR, which is considered as a part of higher power demanded and more complex power system architecture for next generation missions of various orbits. Moreover, the qualifications test results and details are presented.

mortality rates (HR=1.55, 95% CI 1.04-2.30, p=0.03) compared to the "average weight" BMI group. Interestingly, overweight and obese class I but not Obese class II and III patients showed statistically significant earlier engraftment in the form of documented increase of absolute neutrophilic count (ANC) to 500/mL (P value 0.01 and < 0.0001 respectively). Conclusions: BMI 35 is a risk factor for increased mortality after allogenic HSCT after accounting for impacts of comorbidities. Pre-transplant weight reduction to a goal of BMI <35 whenever possible may be a reasonable strategy to improve survival and lower the likelihood to develop Cgvhd after allogenic HSCT, although this approach needs to be studied in a clinical trial. There is a rationale to consider T cell depletion for patients with pre-transplant BMI 35.