K.H. Cameron

Three generations of telecare of the elderly.

The increasing number of elderly and infirm people living alone in their own homes is creating the need for new personal emergency response systems based on public telephone and cable networks. While existing systems enable clients to summon help in the event of illness, future services are likely to make use of evolving technologies to provide automatic sensing of emergencies and to predict long-term deterioration in health, using activity profiles. The characteristics and requirements of these second-generation systems are discussed and predictions are made about the innovative services and facilities that may be available in third-generation systems, when broadband communication is available to the home.

Fetal telemedicine: interactive transfer of real-time ultrasound and video via ISDN for remote consultation

Current referral practice for ultrasonically detected fetal abnormalities contributes to parental anxiety, patient inconvenience, diagnostic inaccuracy, and service inefficiency. To determine whether telemedicine would reduce these disadvantages, we established an ISDN 30 link between a district general hospital on an island and a subspecialty referral center approximately 120 km away on mainland Britain. Live ultrasound images of the fetus were transmitted in real time from a commercial scanner in the hospital using a total data transfer rate of 2 Mbit/s. After decompression at the receiving end, there was almost no perceptible loss of picture quality or frame rate. This report describes the technical aspects of the link and discusses the implications for referral practice in fetal medicine.

Continuous assessment of the risk of falling using telecare

The prevention of falls in the elderly could be based on risk assessment and the prediction of when an individual is likely to sustain an injury. A telecare system should allow the dynamic assessment of risk to be produced by a control centre computer, based on data transmitted from local sensors in the elderly persons home. A fall risk index could be calculated from mobility, activities of daily living and medication. However, substantial data-sets will be required before such fall risk indices attain statistical significance. As they are developed, fall prediction algorithms could be constantly reviewed and modified in order to reach the point where an acceptable level of accuracy is reached.

Recent Developments In The Packaging Of Single-Mode Optical Components And Their Potential Impact On The Future Of Single-Mode Technology

The first generation of components for use in single-mode optical fibre transmission systems are now becoming commercially available. To achieve the full potential of single-mode technology, however, new automated packaging techniques are required that will result in a significant reduction in packaging costs, and that will also allow the production of new advanced hybrid components. This paper briefly reviews new techniques for packaging single-mode optical components that are under development at the British Telecom Research Laboratories.

Realtime three-dimensional remote medical skills acquisition

Three-dimensional techniques are gaining widespread use in a number of disciplines, including medicine, where the visualization of depth information is not only useful but important. Both computer-generated 3-D imaging and 3-D video are set to become increasingly important tools for both diagnosis and teaching. In this paper we will present some of the work that we are currently undertaking using 3-D techniques for remote surgical skills acquisition. This work is based on the use of a small headset with twin miniature video cameras, video codecs, two different 3-D visualization systems and BTs ISDN telecommunications network.

Frequency standards at 1.523 μm based on 20Ne and at 1.56 μm derived from the 0.780 μm Rb frequency standard

This paper reports experimental work towards a laboratory standard based on the 20Ne transition at 1.523 micrometers , some calibration measurements to 2.5 parts in 107 on lines of C2H2 between 1.52 and 1.545 micrometers , and investigation of a standard at 1.56 micrometers involving a CO line. Progress is described towards measurement of the latter line by frequency doubling to, and beating against, a Rb D2-line stabilized laser at 0.780 micrometers of known frequency.

Accessing properties for the delivery of telecare services in an emergency

As telecare systems replace traditional social alarms, service providers must change their operating procedures to deal with increasing numbers of people who need emergency responses to a range of different emergency situations. The telecarers or teleresponders will need immediate access to properties that they have probably not previously visited. This must be managed securely using digital access codes that operate either electronic door locks or key‐safes that contain the relevant key(s). This approach must offer a robust and reliable method of gaining access, which is acceptable to insurance companies, to service users and their families and to the emergency services. This paper describes the strengths and limitations of practical solutions, yielding a list of best practice principles, which should be adopted by telecare service providers.

Electronic tuning of LEC lasers

A key element in any optical system is the light source and semi-conductor lasers have become the most attractive candidates for many applications due to their small size, low drive voltages and high output powers. However, their linewidths need to be reduced for operation at ever-increasing modulation rates. Monolithic laser designs such as the distributed feedback (DFE) and distributed Bragg reflector (DER) produce line-narrowed outputs by including an internal grating within the laser cavity [1). If the cavity is extended beyond the active semi-conductor chip then this long external cavity arrangement, with a reflector at the end, can produce far greater line-width reductions provided that a mechanism is included for selection of a single longitudinal lasing mode [2). Applications for tunable LEC lasers have increased dramatically in recent years and now extend from local oscillators in coherent detection schemes to testing of optical components such as filters and amplifiers and they might in future also be employed in sophisticated fibre optic sensor systems. Various designs have been proposed for mechanical arrangements which would enable wide-range tuning whilst maintaining a single longitudinal mode [3-5) but, in practice, suffer from backlash, hysteresis and slow operation which make them non—ideal for field operation. In the present work we seek an improved control system which will enable wavelength tuning to be performed with the ease and consistency of the electronic tuning schemes.

Subminiature package external cavity laser

A packaged subminiature external cavity laser with a linewidth of <70 KHz has been developed. The package has outside dimensions of 45 X 20 X 15 mm and is designed with a 10 mm cavity making it capable of direct modulation up to 2.4 Gbit/s. The wavelength is selected during manufacture to within the range 1510-1560 nm with an accuracy of 0.05 nm.