Abstract: A method of analysing a bone model, the bone model including an array of finite elements, the method including the steps of: i. simulating the application of a load to a selected plurality of the elements and ii. limiting the selected elements so that each moves an equal distance when the load application is simulated.

Abstract: A method is disclosed for identifying the presence or concentration of a target species in a sample by transmitting a wave of ultrasonic vibration through the sample and calculating, from measured values for time of flight of the wave through the sample and its attenuation during that time, an identification parameter dependent on the type or concentration of the target species in the sample and independent of the distance travelled by the wave through the sample. The method is more convenient to use than existing identification techniques because of the removal of distance from the measurements and calculations necessary. The method is of particular use in identifying polymers, for example, in reclamation and recycling processes. An apparatus for performing the method is also disclosed.

Abstract: An ultrasound bone analysis apparatus having locating means (14) such as a foot bed, for locating a patient's body part in a predetermined position, and a pair of ultrasonic transducers (20, 22) for use in taking ultrasonic measurements of the body part. Each transducer includes a body part contacting portion (19), such as a silicone pad, for ultrasonic contact with the body part. The apparatus further includes means for moving the body part contacting portion of each transducer relative to the body part for allowing the contact of each transducer with the body part to be more accurately controlled. The apparatus also includes pressure control means for controlling the pressure with which the body part contacting portion of the transducers contacts the body part. This allows the compression of the body part contacting portion to be maintained at a constant value and therefore for the measurements to be more accurate.

Abstract: In the apparatus disclosed herein, a bone containing body member to be tested is placed between a pair of transducers and a predetermined sequence of tone signals having frequencies spanning a range from 200 to 600 kilohertz is transmitted through the body member, and the set of values representing the amplitudes of the corresponding received signals are stored. The set of values obtained with the body member between the transducer is normalized using a set of values obtained from the same sequence without the body member in place thereby to generate a third set of values which are compensated for the response characteristics of the transducer and related interfaces. A value corresponding to the rate of change of attenuation with respect to frequency is then calculated from the third set of values and is adjusted for the bone thickness, this adjusted value being related to characteristics of the body member. The bone thickness is determined by a broadband pulse echo measurement.