To analyze a network of conductors, especially an electrical power supply network, it is planned to measure the spectral (49) and temporal (50) nature of a signal available at a node of the network. An image (49 51) representing this state is produced. This image produced is compared with an expected image (52 55) showing an <<on >> state of one and/or the other of the appliances connected to this network. The state of the appliances, whether on or off, is deduced therefrom. This information can be used to optimize the use of the electrical power or to monitor the activity of the appliances concerned.

A small and portable instrument for measuring blood sugar level of a human body noninvasively with no error comprising a light source control section for irradiating the measurement part of a finger with irradiation lights in two different near-infrared wavelength regions, photodetectors for receiving lights and of the irradiation lights quantities of transmitted lights. A relative transmittance, i.e. the ratio of the quantities of transmitted lights of the same wavelength detected at the two positions, is calculated for each wavelength and the blood sugar level is determined using the relative transmittance of each wavelength.

A glucose measuring device for determining the concentration of glucose in intravascular blood within a body part of a subject. The device includes at least one light source having a wavelength of 650, 880, 940 or 1300 nm to illuminate the fluid. At least one receptor (14) associated with the light source (12) for receiving light and generating a transmission signal representing the light transmitted is also provided. A support piece is including for supporting the light source associated with the respective receptor. The support piece is adapted to engage a body part of a subject. Finally, a signal analyzer determines the glucose concentration in the blood of the subject. A method for determining the glucose concentration is also provided which calibrates a measuring device and sets the operating current for illuminating the light sources during operation of the device. Once a transmission signal is generated by receptors (14) receiving light via the light source and illuminated blood, and the high and low values from each of the signals are selected and stored in the device (20), the values are subtracted to obtain a single transmission value for each of the light sources. These calculated values are then compared to a database of target transmission values, either using a neural network, or directly compared to determine the glucose concentration, which value is then displayed (28) on the device.

An aqueous control solution is disclosed for use with a spectrophotometer or photometric test strip that includes a predetermined amount of an analyte, a hydrophobic reference dye and a surfactant. In one embodiment, the aqueous control solution is applied to a photometric test strip having a chemical that oxidizes glucose and consequently forms hydrogen peroxide which reacts with an indicator dye that is also present on the strip. In this embodiment, the control solution includes a predetermined amount of glucose, an infrared reference dye, sodium dodecyl sulfate, and the indicator dye, such as sulforhodamine B.

A system and method for determining the concentration of analytes of interest in complex matrices is provided. According to one aspect of the present invention, near-infrared analytical radiation is generally directed onto a portion of a specimen containing the analyte of interest. A wavelength of the analytical radiation is scanned over the specimen over a broad range of frequencies and over a short duration of diagnostic time. A spectrum of radiation is transmitted through, reflected from or scattered from the specimen and collected by a detector. The concentration of the analyte of interest in the specimen is determined by the radiation collected by the detector.