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Helping to abstract a valid model from real system, conceptual modeling is an essential phase in simulation development lifecycle. With the development of the KAMA framework, a new methodology was presented to develop mission space conceptual model for simulation systems. It provides metamodel elements represented by graphical diagrams to develop conceptual models of mission space. BOM (Base Object Model), developed by SISO (Simulation Interoperability Standards Organization), is another conceptual modeling concept serving for simulation space. KAMA models are very close to problem domain and intend to model real world concepts in requirement analysis and development phase. Whereas, being vital inputs for the simulation design phase, BOM models are closer to solution domain. Hence there is no defined way of using the captured mission space knowledge in simulation space, problem arises when moving from requirement analysis to design phase. In this study, to solve this problem, we propose a method for transforming mission space conceptual models in simulation space. Our solution approach will be mapping the KAMA mission space models to BOM simulation space models for automatically transport real world analysis results to simulation designers.

The space simulation chambers at Arnold Engineering Development Complex (AEDC) allow for the testing and calibration of seeker sensors in cryogenic, high vacuum environments. During operation of these chambers, contaminant films can form on the components in the chamber and disrupt operation. Although these contaminant films can be composed of many molecular species, depending on the species outgassed by warm chamber components and any leaks or virtual leaks (pockets of gas trapped within a vacuum chamber) that may be present, water vapor is most common, and it will be the focus of this dissertation. In this dissertation, some properties of the water molecule and low pressure ice are reviewed with a focus on the optical properties. The method of angular coefficients is utilized to calculate flux distributions for general three dimensional situations and the program written is applied to a model of the AEDC 10V space simulation chamber. The optical effects of varying amounts of contamination on a generic germanium window and gold mirror, along with the effects on two components specific to the space chambers, is determined. Also, an experiment to measure the thickness and other properties of contaminant films is discussed, and initial results are given for the first two tests of the experimental setup.

The space environment possesses numerous unique and unusual attributes, creating challenges that must be considered in order to accomplish a successful space mission. Two of the detrimental aspects of the space environment include Atomic Oxygen, AO, and Ultraviolet, UV, radiation. UV radiation becomes more severe in space as there is no atmosphere to attenuate incoming photons, thereby exposing spacecraft to radiation that never reaches the surface of the Earth. Overall, space vehicles are exposed to a total of 107.4 Watts/m2 of light shorter than 400 nm. AO is created by the photo disassociation of molecular oxygen by UV radiation with wavelengths less than ~242.1 nm. AO is a major portion of the neutral atmosphere, and is the dominant species for altitudes between 180 and 675 km. Each of these environments can cause significant damage to spacecraft materials as they have sufficient energy to break molecular bonds: a generalization of AO energy is 4.5 +/- 1 eV while Vacuum Ultraviolet, VUV, radiation can break bonds as strong as 12.4 eV. Synergistic affects are observed when these two environments interact with materials simultaneously, resulting in an accelerated erosion rate. An apparatus has been developed in California Polytechnic State University’s, Cal Poly’s, space environments laboratory that can simulate the AO and VUV environments individually and simultaneously. This apparatus utilizes a radio frequency, RF, generator to produce a capacitively coupled plasma to create AO in conjunction with a deuterium lamp capable of emitting UV radiation as short as 115 nm. The system has been shown to produce an AO flux of 1.70 +/- 0.07•1016 atoms/cm2 while providing an equivalent sun power 4.5 times greater the solar output in the 120-200 nm region of UV light; all of this has been performed at a base pressure near 175 mTorr. Long duration tests of 24 hours, which would be analogous to durations used in a material interaction study, have shown an effective fluence of 1.47 +/- 0.06•1021 atoms/cm2, which would equate to an orbital exposure on the order of weeks to months. For the same duration a sample can be exposed to 108 equivalent sun hours of 120-200 nm radiation. Results from the simultaneous exposure also manifested an accelerated erosion rate, the expected synergetic reactions between the two environments.

This thesis is aimed at simulation of auditory space. It describes the most frequently used panning method: Vector Base Amplitude Panning. Also is focused on image source method, which allows computing the parameters of direct sound wave and reflections in rectangular room. This method is compared with ray–tracing method, which is also often used. It deals with the matter of the frequency – dependent absorption of materials in reflection of the sound wave against the wall. On the basis of these information two applications were designed in MATLAB development environment. The first one allows the simulation of auditory space. The other one is the application for sound source panning by its azimuth and distance.