Optical measurement methods in thermogasdynamics

A review is presented of a number of optical methods of flow measurements. Consideration is given to such spectroscopic methods as emission and absorption techniques, electron beam-stimulated fluorescence, and light scattering - Rayleigh, Raman and Mie - methods. The following visualization methods are also discussed: shadow photography, schlieren photography, interferometry, holographic interferometry, laser anemometry, particle holography, and electron-excitation imaging. A large bibliography is presented and the work is copiously illustrated with figures and photographs

A Comparative Look at Immigration and Human Capital Assessment

This article examines the formation of an immigration policy designed to build up the skill and human capital of a country. We discuss how the process of selecting economic-stream migrants could be designed to yield economic benefits to the host country. Part I examines the theoretical considerations involved in framing a policy that governs economic-stream immigration. In this section, we outline the goals that a host country seeks to achieve in selecting these migrants and propose important elements of a selection scheme. Part II takes a comparative look at existing points-based schemes for selecting economic migrants, focusing on Canada and Australia. Part III briefly discusses practical barriers to implementing such a system in the United States. The article concludes that the United States should enact a points-based system for selecting economic-stream migrants. It is impossible to cover this subject exhaustively in one article. For that reason, this article only discusses the immigration of high-skilled workers, not low-skilled or agricultural workers. We also only discuss permanent immigration, not temporary workers. Finally, as others studying this area know, we are all handicapped by a lack of good statistical or economic data. We discuss several studies that have sought to evaluate the economic success of economic-stream migrants over time, but these studies are limited in scope, the time period covered, and their ability to establish a clear link between selection criteria and the economic results that were measured. Thus, our recommendations should be considered skeptically. As discussed below, we are not sure what has worked best in other countries, let alone how policy changes would work in the U.S. context