Measurement of vehicle contamination by exhaust gases. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

An investigation of site effects on roadside measurement of truck noise. Final report.

Transportation Department, Office of Noise Abatement, Washington, D.C.

New concepts for traffic barrier systems. Final report.

Federal Highway Administration, Structures and Applied Mechanics Division, Washington, D.C.

Diagnostic motor vehicle inspection demonstration projects, program engineering support. Volume 2 - appendix A: evaluation of the measurement performance of inspection equipment in the five demonstration projects and in selected repair agencies. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

An initial assessment of the literature on the measurement, control, transport, transformation and health effects of unregulated diesel engine emissions. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Development and evaluation of Hybrid III multi-point thoracic deflection measurement sensors. Final report.

Mode of access: Internet.

Measurement of interactive computing : methodology and application /

Thesis--George Washington University.

Application of measurement criteria in the selection of interactive computer services /

"Issued April 1980."

Objective measurement of voice channel intelligibility /

Mode of access: Internet.

The fourteen systems of units /

Bibliography: p. [219]

Proceedings of the 1986 EPA/APCA Symposium on Measurement of Toxic Air Pollutants /

"EPA Report No. 600/9-86-013"--P. ii.

A probe for the measurement of high surface temperatures. [Technical report AFFDL-TR-65-121.

"This report was prepared by Cornell Aeronautical Laboratory, Inc., Buffalo, New York under USAF Contract no. AF-33(615)-1485."

Practical considerations for the measurement of free light chains in serum

Background: A new immunoassay for free light chain measurements has been reported to be useful for the diagnosis and monitoring of monoclonal light chain diseases and nonsecretory myeloma. We describe experience with and some potential pitfalls of the assay. Methods: The assay was assessed for precision, sample type and stability, recovery, and harmonization of results between two analyzers on which the reagents are used. Free-light-chain concentrations were measured in healthy individuals (to determine biological variation), patients with monoclonal gammopathy of undetermined significance, myeloma patients after autologous stem cell transplants, and patients with renal disease. Results: Analytical imprecision (CV) was 6-11% for kappa and A free-light-chain measurement and 16% for the calculated kappa/lambda ratio. Biological variation was generally insignificant compared with analytical variation. Despite the same reagent source, values were not completely harmonized between assay systems and may produce discordant free-light-chain ratios. In some patients with clinically stable myeloma, or post transplantation, or with monoclonal gammopathy of undetermined significance, free-light-chain concentration and ratio were within the population reference interval despite the presence of monoclonal intact immunoglobulin in serum. In other patients with monoclonal gammopathy of undetermined significance, values were abnormal although there was no clinical evidence of progression to multiple myeloma. Conclusions: The use of free-light-chain measurements alone cannot differentiate some groups of patients with monoclonal gammopathy from healthy individuals. As with the introduction of any new test, it is essential that more scientific data about use of this assay in different subject groups are available so that results can be interpreted with clinical certainty. (C) 2003 American Association for Clinical Chemistry.

Geometric distortion in clinical MRI systems - Part I: evaluation using a 3D phantom

Recently, a 3D phantom that can provide a comprehensive and accurate measurement of the geometric distortion in MRI has been developed. Using this phantom, a full assessment of the geometric distortion in a number of clinical MRI systems (GE and Siemens) has been carried out and detailed results are presented in this paper. As expected, the main source of geometric distortion in modern superconducting MRI systems arises from the gradient field nonlinearity. Significantly large distortions with maximum absolute geometric errors ranged between 10 and 25 mm within a volume of 240 x 240 x 240 mm(3) were observed when imaging with the new generation of gradient systems that employs shorter coils. By comparison, the geometric distortion was much less in the older-generation gradient systems. With the vendor's correction method, the geometric distortion measured was significantly reduced but only within the plane in which these 2D correction methods were applied. Distortion along the axis normal to the plane was, as expected, virtually unchanged. Two-dimensional correction methods are a convenient approach and in principle they are the only methods that can be applied to correct geometric distortion in a single slice or in multiple noncontiguous slices. However, these methods only provide an incomplete solution to the problem and their value can be significantly reduced if the distortion along the normal of the correction plane is not small. (C) 2004 Elsevier Inc. All rights reserved.

Quantum nondemolition measurement of Fock states of mesoscopic mechanical oscillators

We investigate a scheme that makes a quantum nondemolition (QND) measurement of the excitation level of a mesoscopic mechanical oscillator by utilizing the anharmonic coupling between two beam bending modes. The nonlinear coupling between the two modes shifts the resonant frequency of the readout oscillator in proportion to the excitation level of the system oscillator. This frequency shift may be detected as a phase shift of the readout oscillation when driven on resonance. We derive an equation for the reduced density matrix of the system oscillator, and use this to study the conditions under which discrete jumps in the excitation level occur. The appearance of jumps in the actual quantity measured is also studied using the method of quantum trajectories. We consider the feasibility of the scheme for experimentally accessible parameters.