Abstract: A flexible sensor tube for determining a concentration curve of a medium along a path includes a flexible tube being formed of a material having good permeability to the medium and having an inner surface being completely provided with a thin coating of a material having poor permeability to the medium. A flexible tube of a material having good permeability to the medium may also be coated on the inner surface with a material being impermeable or having poor permeability to the medium, with a narrow strip extending in the longitudinal direction of the flexible tube being left free. In addition, a band being formed of a material being impermeable or having poor permeability to the medium, can be bent into the shape of a trough, while a slot-like aperture remains free. The slot-like aperture is closed by a strip being formed of a material having good permeability to the medium and extending in the longitudinal direction of the band.

Abstract: The monitoring assembly for a landfill or garbage dump comprises two sensor hoses, which are laid on both sides of a sealing liner parallel to each other. A transport medium can flow through the sensor hoses in the same or in opposite directions. First and second indicator signals are determined with the aid of at least one detector. The indicator signals indicate the presence of a pollutant in the transport medium and thus in the relevant sensor hose. These signals are logically combined with each other, with regard to location, preferably subtracted from each other. The resulting signal distinctly shows an extreme value in its curve as soon as a leak is present in the sealing liner. The position can be easily determined from that graphic representation.

Abstract: A monitorable device for sealing off a body, in particular a garbage dump or a landfill, includes two seals sealing off a body and being mutually spaced-apart defining a control chamber between the seals. The control chamber has connections for an inlet opening and an outlet opening and is otherwise closed. A permeable channel or hose is connected between the inlet opening and the outlet opening in the control chamber for carrying a transport medium. A lance which is used for supplying a tracer gas may be disposed outside the control chamber and may face toward one of the seals. A sensor is connected to the outlet opening for detecting the tracer gas. A method for monitoring a device for sealing off a body includes sealing off a body with two seals being mutually spaced-apart defining a control chamber between the seals being closed except for connections for an inlet opening and an outlet opening.

Abstract: A device for sealing off and monitoring a volume includes two seals. Support elements space the seals apart from one another. At least one conduit is disposed between the seals and the support elements. The at least one conduit has an inlet opening and an outlet opening for a medium. At least one sensor is associated with the outlet line. The two seals have edges being tightly joined to one another leaving the inlet and outlet openings of the at least one conduit free. The support elements are formed of a flow-hindering material. At least two devices may be tightly joined together to form a field, with the outlet opening of the at least one conduit of one of the at least two devices being connected to the inlet opening of the at least one conduit of another of the at least two devices.

Abstract: Ultrasonic testing device with a test head which includes an electromechanical transducer, especially a piezoelectric oscillator, with an ultrasonic equipment and with a shielded cable which connects the test head to the ultrasonic equipment. The test head has two electrically conducting shields which surround the transducer in cup-fashion. The two shields are connected to the outer conductors of the triple coaxial cable. The outer conductor of the cable is connected to a metal housing of the ultrasonic equipment and is grounded.

Abstract: A concentric three-conductor cable includes an inner conductor and outer conductors formed of braided strands, and insulating material separating the outer conductors from each other and from the inner conductor, each the other conductors being formed of a plurality of layers and the d-c resistance of the outer conductors being several times smaller than the d-c resistance of said inner conductor.

Abstract: Test equipment for the detection and analysis of material faults in a test piece, including a test head, an electrical remotely controlled manipulator for moving the test head in at least two degrees of freedom, a device connected to the test head for supplying the test head and evaluating signals thereof, a display connected to the test head for measuring test results thereof, a device for providing the manipulator with a testing program for automatically following a predetermined path at the surface of the test piece, an electronic transmission system connected to the manipulator, a device connected to the electronic transmission system for simulating the test piece, and a remote controlled hand-operated guide element disposed adjacent to the display in the simulating means for controlling the test head in correspondence to manual operation.