Computer-aided design and analysis of mechanisms

An introduction to the computer programs developed to assist in the design and analysis of mechanisms is presented. A survey of the various types of programs which are available is given, and the most widely used programs are compared. The way in which the programs are used is discussed, and demonstrated with an example

Recycling of quantum information: Multiple observations of quantum clocks

How much information about the original state preparation can be extracted from a quantum system which already has been measured? That is, how many independent (non-communicating) observers can measure the quantum system sequentially and give a nontrivial estimation of the original unknown state? We investigate these questions and we show from a simple example that quantum information is not entirely lost as a result of the measurement-induced collapse of the quantum state, and that an infinite number of independent observers who have no prior knowledge about the initial state can gain a partial information about the original preparation of the quantum system.Comment: 4 page

Dissipation-assisted quantum computation in atom-cavity systems

The principal obstacle to quantum information processing with many qubits is decoherence. One source of decoherence is spontaneous emission which causes loss of energy and information. Inability to control system parameters with high precision is another possible source of error. Strategies aimed at overcoming one kind of error typically increase sensitivity to others. As a solution we propose quantum computing with dissipation-assisted quantum gates. These can be run relatively fast while achieving fidelities close to one. The success rate of each gate operation can, at least in principle, be arbitrary close to one.Comment: proceedings for the SPIE conference on Fluctuations and Noise, June 2003 in Santa Fe, 12 pages, minor change

Development of a 25 - 50 watt high efficiency, X-band, traveling wave tube Quarterly report, Nov. 1970 - Jan. 1971

Computer design technique of electron gun for use in spacecraft transmitter

Generating optimal states for a homodyne Bell test

Published versio

A New Look at Racial Profiling: Evidence from the Boston Police Department

This paper provides new evidence on the role of preference-based versus statistical discrimination in racial profiling using a unique data set that includes the race of both the driver and the officer. We first generalize the model presented in Knowles, Persico and Todd (2001) and show that the fundamental insight that allows them to distinguish between statistical discrimination and preference-based discrimination depends on the specialized shapes of the best response functions in their model. Thus, the test that they employ is not robust to a range of alternative modeling assumptions. However, we also show that if statistical discrimination alone explains differences in the rate at which the vehicles of drivers of different races are searched, then search decisions should be independent of officer race. We then test this prediction using data from the Boston Police Department. Consistent with preference-based discrimination, our baseline results demonstrate that officers are more likely to conduct a search if the race of the officer differs from the race of the driver. We then investigate and rule out two alternative explanations for our findings: race-based informational asymmetries between officers and the assignment of officers to neighborhoods.

Optimization of controlled environments for hydroponic production of leaf lettuce for human life support in CELSS

A research project in the food production group of the Closed Ecological Life Support System (CELSS) program sought to define optimum conditions for photosynthetic productivity of a higher plant food crop. The effects of radiation and various atmospheric compositions were studied