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"Kimberly Drew and Jenna Wortham have brought together this collection of work—images, photos, essays, memes, dialogues, recipes, tweets, poetry, and more—to tell the story of the radical, imaginative, provocative, and gorgeous world that Black creators are bringing forth today. The book presents a succession of startling and beautiful pieces that generate an entrancing rhythm: Readers will go from conversations with activists and academics to memes and Instagram posts, from powerful essays to dazzling paintings and insightful infographics." -- Publisher's website.

"Kimberly Drew and Jenna Wortham have brought together this collection of work—images, photos, essays, memes, dialogues, recipes, tweets, poetry, and more—to tell the story of the radical, imaginative, provocative, and gorgeous world that Black creators are bringing forth today. The book presents a succession of startling and beautiful pieces that generate an entrancing rhythm: Readers will go from conversations with activists and academics to memes and Instagram posts, from powerful essays to dazzling paintings and insightful infographics." -- Publisher's website.

The need for good aircraft handling qualities has been apparent since the days of the Wright Flyer. In the past decade, there has been a perception that this need has lessened as advanced concepts have evolved, in parallel with acquisition reform. The former has led those who are unfamiliar with the field of handling qualities to conclude that quantitative requirements are not necessary, as the latter has resulted in the elimination of the military specifications for handling qualities. This paper reviews the evolution of handling qualities and their specifications. It presents some ongoing challenges in the field to illustrate that handling qualities are still a critical issue for future aircraft.

The Air Vehicles Directorate formed the Control Science Center of Excellence (CoE) in 1998. The mission of the Control Science CoE is to plan and conduct basic research and exploratory development in advanced control technology to support the Air Force in the 21st century. The CoE develops and transitions air and space vehicle control technology in the areas of flight dynamics, multi variable control theory, adaptive control theory, robust control, control optimization, system identification, and flight and space vehicle simulation and assessment. The Control Theory Optimization Branch was established as a Center of Excellence in recognition of its consistent productivity over the last twenty years and its many fundamental technical contributions to control theory. The CoE has successfully transitioned technology to several operational systems and the scientists and engineers of the CoE have earned recognition from professional associations, universities, and other government and DoD organizations., Original contains color plates: All DTIC reproductions will be in black and white.

We have identified proteins that are abundant in affinity-purified proteasomes, but absent from proteasomes as previously defined because elevated salt concentrations dissociate them during purification. The major components are a deubiquitinating enzyme

Modern optimal control techniques are used to design a digital controller for a large flexible space structure. The structure is modeled as a tetrahedron formed by four lumped masses connected by massless truss members. A NASTRAN analysis is used to generate the twelve mode shapes and frequencies of oscillation. The controller is designed in discrete-time using linear optimal regulator theory. An observer is used to estimate the states. Active control is achieved using six collocated sensor actuator pairs. The effectiveness of the controller is determined using pointing accuracy as a figure of merit. Three controller designs are compared. The first demonstrates the effects of 'control' and 'observation spillover.' The second uses a singular value decomposition to eliminate the spillover terms. The third design uses a more accurate optimal performance index than the first two. The first design proved inadequate to achieve the desired performance. The second and third designs were able to achieve the desired performance for small sampling times. For small sampling times the simplified performance index used in Design II proved to provide a very accurate approximation to the optimal. (Author)

Capital asset pricing theory assumes a no-tax, after-tax efficiency equivalence; ie., that the efficient information produced in a no-tax analysis is equivalent to that which is produced in an after-tax analysis. However, if the effect of income taxes is not systematic throughout the market, the useful application of the theory may be impaired by this assumption. This research seeks to determine the effect of income tax imposition on the risk-return expectations or individual investors. If the effect of income tax imposition is to produce non-homogeneous after-tax investor risk-return expectations, then the efficiency equivalence hypothesis must be rejected. This efficiency equivalency hypothesis is evaluated by testing two alternative hypotheses, (1) the systematic riskiness of any individual security, both with and without adjustment for the imposition of income tax, is equivalent, and (2) the no-tax and after-tax expected risk-return rank order of each individual security is the same. An after-tax capital asset pricing model is derived. This model is based upon the premise that the current income tax laws, which require investors to share with the taxing government the uncertain returns from risky assets, allow investors to reduce the riskiness of those returns. The returns on investment assets are derived from both capital gains and from ordinary income distributions. However, the tax treatment of capital gains (losses) and ordinary income (dividends/interest) is not the same. This results in an unsystematic effect on the risks and returns of investments, thus, the income tax effect is not likely to be homogeneous as an efficiency equivalence hypothesis would imply. The analysis focuses on the expected risk-return equivalencies for 465 firms, using ex-post data over a 10 year period. The findings of this study imply that income tax effects on the market are not homogeneous. Income tax differentials are apparent in both the observed beta terms and the risk-return