The design, construction and details of operation of an instrument for measuring Bidirectional Scattering Distribution Functions (BSDF) {i.e., Bidirectional Reflection Distribution Functions (BRDF) and Bidirectional Transmission Distribution Functions (BTDF)} at four wavelengths from the visible to the far infrared (FIR) are presented. Hardware, software, theory, calibration, accuracy and performance are all addressed. The four major interacting subsystems--optical, electronic, mechanical and computer--are discussed in various degrees of detail. A BASIC language control program for running the system via the Z-80 microprocessor is included in the appendix. The origin of BRDF is traced, and a brief theoretical summary examines it from both a physical optics and a radiometric point of view. Modeling is performed to determine the effect of large radiometer collecting apertures on accuracy. Dynamic range and resolution are determined from experimental and theoretical considerations. Finally, new measurements of Martin Black at 118.8 (mu)m are presented along with measurements at 0.6328, 3.39 and 10.6 (mu)m. The FIR BRDF measurements covered 6 orders of magnitude and values as low as 6 x 10('-4) sr('-1) have been recorded.

Unobscured reflective optical systems can be more transmissive and of higher diffraction quality than classical systems. Unobscured systems are generated by decentering symmetric systems, tilting elements to correct coma or astigmatism along a real ray, or by cross-tilting elements to control astigmatism. Such a system of relatively high quality may be further corrected with a general spline surface. For spline surfaces, optical aberration coefficients are undefined. This study developed real ray analysis and design techniques for general optical systems. A decentered symmetric system with a field correcting spline surface was designed. The optical design program ACCOS V was used for most design and analysis tasks. Design and analysis of general systems are considered first. Basic system quantities of image location, scaling, and irradiation are defined with real rays. Spline surfaces are discussed with special emphasis on features important in optical design. Real ray analytical techniques of composite spot diagrams across the image, footprints on spline surfaces, wavefront aperture maps, and spline surface maps are described. The use of these tools in general system design procedures is discussed. Standard telescope objectives of f/8.5 were considered as base designs for systems with spline surfaces. A spline surface was added to the decentered Schmidt-Cassegrain. Optimization yielded diffraction-limited performance across a 0.85 degree square field. The spline system was compared to the Galileo spacecraft narrow angle lens and a three-mirror decentered design. It had a far wider field than the Galileo but at a lower quality. Diffraction quality was better than that of the three-mirror system. Simple tolerances were considered for the spline system. The allowable effect of a thermal gradient was estimated by bending the reference axis. Decentration and figure tolerances for the spline were commensurate with classical surfaces. Techniques presented were shown to be useful for design and analysis of general systems. Spline surfaces were found to be useful in optimization of such systems. This work was supported by the Director's Discretionary Fund, Jet Propulsion Laboratory, California Institute of Technology.

One way to engage with ethics is in a thoughtful way. Chapter 1 shows that there is disagreement about the value of ethical thoughtfulness. Chapter 2 gives a careful account of ethical thoughtfulness in terms of four norms. Chapter 3 shows that being ethically thoughtful is possible for many of us, but is also likely to be costly. Chapter 4 argues that connections between ethical thoughtfulness and behavior do not provide compelling reasons to pursue ethical thoughtfulness. Chapter 5 argues that ethical thoughtfulness is not significant because of connections to moral epistemology, moral accountability, or moral standing. Chapter 6 argues that it is unlikely that ethical thoughtfulness is good for all humans, but that it may be a good for some people in some circumstances.

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M.Sc. (Chemistry) / A brief discussion of gas-solid interactions is given. The choice of reflection-absorption infrared spectroscopy (RAIRS) and the Kelvin probe as surface analytical techniques resulted in a visit to the physical research laboratory of Prof. J, Pritchard at Queen Mary College (London) . At this laboratory the author took part in the development of a wavelength modulation spectrometer. A spectrometer in the RAIRS mode and a Kelvin probe were used to study the adsorption of CO on a Cu(110) single crystal ...

A concrete description of Hochschild cohomology is the first step toward exploring associative deformations of algebras. In this dissertation, deformation theory, geometry, combinatorics, invariant theory, representation theory, and homological algebra merge in an investigation of Hochschild cohomology of skew group algebras arising from complex reflection groups. Given a linear action of a finite group on a finite dimensional vector space, the skew group algebra under consideration is the semi-direct product of the group with a polynomial ring on the vector space. Each representation of a group defines a different skew group algebra, which may have its own interesting deformations. In this work, we explicitly describe all graded Hecke algebras arising as deformations of the skew group algebra of any finite group acting by the regular representation. We then focus on rank two exceptional complex reflection groups acting by any irreducible representation. We consider in-depth the reflection representation and a nonfaithful rotation representation. Alongside our study of cohomology for the rotation representation, we develop techniques valid for arbitrary finite groups acting by a representation with a central kernel. Additionally, we consider combinatorial questions about reflection length and codimension orderings on complex reflection groups. We give algorithms using character theory to compute reflection length, atoms, and poset relations. Using a mixture of theory, explicit examples, and calculations using the software GAP, we show that Coxeter groups and the infinite family G(m,1,n) are the only irreducible complex reflection groups for which the reflection length and codimension orders coincide. We describe the atoms in the codimension order for the groups G(m,p,n). For arbitrary finite groups, we show that the codimension atoms are contained in the support of every generating set for cohomology, thus yielding information about the degrees of generators for cohomology.

My thesis, Condensation, is centered on seeing and the limits of our perceptions. I’m interested in the psychological and emotional effects of visual phenomena and am exploring this area through glass’s ability to reflect and obscure. I’m also experimenting with photography because it’s simply documentation of reflection. The solidity of reflection whether on glass, photography, or water is something that I’m questioning. The viewer assumes its physicality, but what we accept as conclusive is at times a construct. The palpability of reflection then disintegrates into the residue of sight. I’ve been contemplating our eyes perceptual limits and what our mind sees in relation to what’s shown. The act of seeing works as a catalyst to initiate doubt in our perceptions and reminds us of our eyes ability to reveal and conceal information. Visual shifting has led me to question the idea of boundaries in both physical and mental spheres.

Diploma thesis Teacher as a reflective practitioner is divided into theoretical and practical parts. The aim of theoretical part is characteristics of basic concepts related to reflection, dealing with issues of teacher education and opportunities for teachers who have already participated in the educational process. It presents the most commonly used techniques and methods of reflection and self-reflection, but other less common ones have been mentioned as well. The aim of the practical part analyses the current situation of teachers as reflecting practitioners at secondary schools with gastronomic specialization. Diploma thesis compares reflective processes among teachers of general educational subjects, professional courses and training.

<p>The resolution of near-surface seismic reflection data is often limited by attenuation and scattering in the shallow subsurface which reduces the high frequencies in the data. Compensating for attenuation and scattering, as well as removing the propagating source wavelet in a time-variant manner can be used to improve the resolution. Here we investigate continuous non-stationary iterative time-domain deconvolution (CNS-ITD), where the seismic wavelet is allowed to vary along the seismic trace. The propagating seismic wavelet is then a combination of the source wavelet and the effects of attenuation and scattering effects, and can be estimated in a data-driven manner by performing a Gabor decomposition of the data. For each Gabor window, the autocorrelation is estimated and windowed about zero lag to estimate the propagating wavelet. Using the matrix-vector equations, the estimated propagating wavelets are assigned to the related columns of a seismic wavelet matrix, and these are then interpolated to the time location where the maximum of the envelope of the trace occurs within the iterative time-domain deconvolution. Advantages of using this data-driven, time-varying approach include not requiring prior knowledge of the attenuation and scattering structure and allowing for the sparse estimation of the reflectivity within the iterative deconvolution. We first apply CNS-ITD to synthetic data with a time-varying attenuation, where the method successfully identified the reflectors and increased the resolution of the data. We then applied CNS-ITD to two observed shallow seismic reflection datasets where improved resolution was obtained. </p>