Abstract: The disclosure relates to a thermosiphon system operable to consistently maintain the permafrost and active frost layer in a frozen condition to adequately support buildings and other structures. During cooler seasons, the thermosiphon system uses a passive refrigeration cycle to efficiently maintain the frozen layers using the cold air. When the air temperature rises during the warmer months, the system transitions into an active refrigeration mode that uses a refrigeration system to minimize thawing or degradation of the permafrost and active frost layers.

Abstract: The disclosure relates to a waste collection system designed for handling liquid and solid waste without reliance on running water. The system is also designed with modular components adapted for in-home installation, where the system can be quickly assembled and disassembled as needed, such as for moving the components to a new location based on environmental conditions. Moreover, the system is designed to facilitate easy conversions between a waste-separating toilet design and a more streamlined non-waste-separating toilet design when desired to maximize flexibility of the overall system.

Abstract: The disclosure relates to a thermosiphon system operable to consistently maintain the permafrost and active frost layer in a frozen condition to adequately support buildings and other structures. During cooler seasons, the thermosiphon system uses a passive refrigeration cycle to efficiently maintain the frozen layers using the cold air. When the air temperature rises during the warmer months, the system transitions into an active refrigeration mode that uses a refrigeration system to minimize thawing or degradation of the permafrost and active frost layers.

Abstract: An apparatus and method for determining passage along an installation route of an advancing end of an optical fibre. A detector at the installation end detects when light is transmitted back along the fibre from a source at a predetermined location. The source may be a primary source or comprise a means for coupling to a light carrying fibre.

Abstract: The propulsive force on an optical transmission line member moving through a tubular passageway can be varied so the line travels at or close to optimum speed without risk of damage to the line or associated apparatus. A curve is provided in a portion of the passageway such that a transmission line subject to unacceptable compressive forces buckles towards the outer side of the curve. A sensor detects the presence or absence of the line at this point and a control circuit varies the propulsive force. Excessive tension in the fibre may also be detected. A modified system uses deflectors to ensure that buckling occurs by bowing in the direction towards the sensor with the transmission line undeflected under correct tension. The invention finds particular application in a method of fibre blowing where an optical fibre transmission line is propelled along a tube by fluid drag.