Abstract: A method and apparatus are provided for reducing distortion in a dynamically delayed digital sample stream of an imaging system. The method includes the steps of delta-sigma modulating an input analog signal of the imaging system at a frequency above the Nyquist frequency of the input analog signal to generate a digital sample stream and changing a length of the sample stream to delay a portion of the sample stream while maintaining synchronism between a delta-sigma modulator and a demodulator of the system.
Type:
Grant
Filed:
July 20, 1999
Date of Patent:
March 27, 2001
Assignees:
The Regents of the University of Michigan, Q-Dot, Inc.
Inventors:
Steven R. Freeman, Matthew O'Donnell, Thomas E. Linnenbrink, Marc A. Morin, Marshall K. Quick, Charles S. Desilets
Abstract: A nuclear reactor fuel element is described which has an outer cladding, a central core of fissionable or mixed fissionable and fertile fuel material and a layer of oxygen gettering material on the inner surface of the cladding. The gettering material reacts with oxygen released by the fissionable material during irradiation of the core thereby preventing the oxygen from reacting with and corroding the cladding. Also described is an improved method for coating the inner surface of the cladding with a layer of gettering material.
Type:
Grant
Filed:
June 2, 1976
Date of Patent:
October 21, 1980
Assignee:
The United States of America as represented by the United States Department of Energy
Abstract: This disclosure describes a device and method for in situ shortening of nuclear reactor zirconium alloy process tubes which have grown as a result of radiation exposure. An upsetting technique is utilized which involves inductively heating a short band of a process tube with simultaneous application of an axial load sufficient to cause upsetting with an attendant decrease in length of the process tube.
Type:
Grant
Filed:
January 24, 1979
Date of Patent:
August 26, 1980
Assignee:
The United States of America as represented by the United States Department of Energy
Inventors:
Charles E. Frantz, William K. Alexander, Walter E. B. Lander
Abstract: A method and means for measuring the level of a liquid in a container. A coaxial cavity having a perforated outer conductor is partially submerged in the liquid in the container wherein the liquid enters and terminates the annular region of the coaxial cavity. The fundamental resonant frequency of the portion of the coaxial cavity which does not contain liquid is determined experimentally and is used to calculate the length of the liquid-free portion of the coaxial cavity and thereby the level of liquid in the container.
Type:
Grant
Filed:
September 26, 1978
Date of Patent:
October 9, 1979
Assignee:
The United States of America as represented by the United States Department of Energy
Abstract: A tool calibration system including a tool calibration fixture and a tool height and offset calibration insert for calibrating the position of a tool bit in a micromachining tool system. The tool calibration fixture comprises a yokelike structure having a triangular head, a cavity in the triangular head, and a port which communicates a side of the triangular head with the cavity. Yoke arms integral with the triangular head extend along each side of a tool bar and a tool head of the micromachining tool system. The yoke arms are secured to the tool bar to place the cavity around a tool bit which may be mounted to the end of the tool head. Three linear variable differential transformer's (LVDT) are adjustably mounted in the triangular head along an X axis, a Y axis, and a Z axis. The calibration insert comprises a main base which can be mounted in the tool head of the micromachining tool system in place of a tool holder and a reference projection extending from a front surface of the main base.
Type:
Grant
Filed:
December 14, 1977
Date of Patent:
March 6, 1979
Assignee:
The United States of America as represented by the United States Department of Energy