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This paper describes a process to achieve a pre-defined vehicle level interior sound quality target, by a sound engineering cascade to targeted noise and vibration development at the system level. Air-borne and structure-borne contributors to interior sound are identified at the system level using a comprehensive Transfer Path Analysis (TPA) in both the frequency and time domains. For significant contributors, the relative importance of the source system (powertrain) and path system (vehicle) are determined. System level changes are simulated, and their effect on interior sound evaluated using TPA. A set of feasible changes is identified that, when combined, achieves the vehicle level interior sound quality target. This set of changes defines system level targets for noise and vibration development, cascaded from the vehicle level target.

Variable emittance radiator, called SRD, is a thin and light ceramic tile whose infrared emissivity is varied proportionally by its own temperature. Bonded only to the external surface of spacecrafts, it controls the heat radiated to deep space without electrical or mechanical parts such as the thermal louver. By applying this new device for thermal control of spacecrafts, considerable weight and cost reductions can be achieved easily. In this paper, the new design and the new manufacturing process of the SRD and its optical properties, such as the total hemispherical emittance and the solar absorptance, are described. By introducing this new design and manufacturing process, the weight of the SRD is easily decreased, keeping its strength and the optical properties.

The Smart Radiation Device (SRD) which is made from a ceramic material is a thin and light tile. The material undergoes a metal-insulator transition at around 290K and this allows the infrared emissivity of the device to change from low to high as the temperature is increased from 175K to 375K. This is beneficial for thermal control applications on spacecraft. For example, bonded only to the external surface of the spacecraft's instruments, SRD controls the heat radiated to deep space without electrical instruments or mechanical parts used for changing emissivity. It reduces the energy consumption of the electrical heater for thermal control, and decreases the weight and the cost of the thermal control system. In this paper, the design of the new material for SRD and the ground test results such as the radiation tests of electrons and UV will be described.

The Smart Radiation Device (SRD) is a thin and light tile whose infrared emissivity is varied proportionally by the temperature of the radiator. Bonded only to the external surface of the spacecraft’s instruments, it controls the heat radiated to deep space without electrical or mechanical instruments used for changing emissivity. Its function is similar to the thermal louver which has been used for a lot of spacecraft, but the SRD is lighter than it. Thus, by using this new device, we can control the temperature of the instruments on the spacecraft more easily. The materials of the SRD are La0.825Sr0.175MnO3 and La0.7Ca0.3MnO3. In this paper, design and preliminary test results of the SRD will be presented. The optical properties for the materials of the SRD, such as the total hemispherical emittance and the solar absorptance, have been measured. In addition the degradation by protons has been investigated.