Abstract: The present invention relates to a system for measuring the level of granular material in a container immersed in an aqueous medium, particularly, but not exclusively, for use as a measure of sanitizer level in spa and whirlpool halogenation systems. Electrodes fixed in the container wall are used to measure the electrical conductance along a path which is part filled with the granular material. Coils of wire are arranged such that the interrogating signal is coupled inductively to the sensor head. In this way the granule container can be made demountable, with no bare conductor material exposed to the aqueous medium. A separate reference circuit is used to measure the conductivity of the water in the system, and this signal is used to normalize the signal obtained from inside the container.

Abstract: A plurality of computer nodes communicate using seemingly random Internet Protocol source and destination addresses. Data packets matching criteria defined by a moving window of valid addresses are accepted for further processing, while those that do not meet the criteria are quickly rejected. Improvements to the basic design include (1) a load balancer that distributes packets across different transmission paths according to transmission path quality; (2) a DNS proxy server that transparently creates a virtual private network in response to a domain name inquiry; (3) a large-to-small link bandwidth management feature that prevents denial-of-service attacks at system chokepoints; (4) a traffic limiter that regulates incoming packets by limiting the rate at which a transmitter can be synchronized with a receiver; and (5) a signaling synchronizer that allows a large number of nodes to communicate with a central node by partitioning the communication function between two separate entities.

Abstract: The present invention relates to a system for measuring the level of granular material in a container immersed in an aqueous medium, particularly, but not exclusively, for use as a measure of sanitizer level in spa and whirlpool halogenation systems. Electrodes fixed in the container wall are used to measure the electrical conductance along a path which is part filled with the granular material. Coils of wire are arranged such that the interrogating signal is coupled inductively to the sensor head. In this way the granule container can be made demountable, with no bare conductor material exposed to the aqueous medium. A separate reference circuit is used to measure the conductivity of the water in the system, and this signal is used to normalize the signal obtained from inside the container.

Abstract: The invention concerns a method and a system for rapidly establishing a Bluetooth type communication between a reader and a communicating object. The Bluetooth type communication protocol implements a radio frequency communication process on channels having specific frequencies. The specific frequencies are divided into a first subgroup of frequencies and a second subgroup of frequencies. Each communicating object of alternately and successively selects a frequency from the first subgroup of frequencies followed by a frequency from the second subgroup of frequencies. The reader randomly selects the first subgroup of frequencies or the second subgroup of frequencies, and performs frequency scans of the selected subgroup of frequencies before performing a scan of the other subgroup of frequencies.

Abstract: According to an embodiment of the invention, there is disclosed a method of operating a wireless mesh network. The method comprises: seeding the network from a first node; allocating a network address to each member node of the network to form a tree-like structure of the nodes, such that the network address is reversibly derived from the network address of the member node from which it is derived in the tree-like structure; and mapping out cross-branch network connections between nodes that are determined not to be immediate neighbour nodes according to the addresses of the tree-like structure. Further related system embodiments are also disclosed.

Abstract: A three-phase electronic electricity meter that includes configurable voltage sensing blades such that the electricity meter can be configured for use with various electrical service types. The electricity meter includes a base having a configuration to correspond to standard ANSI-type sockets. The meter base includes a plurality of individual voltage sensing blades that are received by the ANSI socket. At least one of the voltage sensing blades is movable between a first and a second position such that the voltage sensing blade contacts different areas on a meter circuit board in the first and second positions. A common circuit board can be utilized for different electrical service types and the contact arrangement can be selectively configured by moving the voltage sensing blades between their first and second positions.

Abstract: A circuit used to control the brightness of a number of light emitting diodes (LEDs) in an array, such that the color and brightness of the light produced by the array may be varied. The circuit is optimized to operate at high efficiency, permitting its use in confined spaces with poor cooling. The circuit permits a variety of configurations of LEDs to be controlled and driven from a range of line voltages. The circuit is further optimized to use few components to achieve its function.

Abstract: An extension indicator is provided for determining a predetermined extension applied to an extensibly deformable article such as medical bandage used in compression therapy. The indicator includes first (420) and second (430) co-operating members, each adapted to be secured to an extensibly deformable article (440). One of the members is more extensible than the other and each member (420, 430) bears visual indicia (450, 460, 470) which upon extension of the more extensible member, are adapted to align with each other to indicate a predetermined extension of the more extensible member.

Abstract: This invention relates to a telecommunications system including a plurality of mobile telephones. The telecommunications system has a switch network including: data storage units (HLR) for storing connection data relating to respective mobile telephones; a register (15) for storing associations between the data storage units and respective identification codes; inputs for inputting an identification code; and a switch unit (30, 31) for interrogating the register (15) to determine the data storage unit (HLR) associated with that identification code. The switch network then uses the connection data stored by the data storage unit (HLR) to form a telecommunication link with the corresponding mobile telephone. The associations stored by the register (15) can be changed.

Abstract: The disclosure herein describes a table with a top plate which may be lowered or raised by rotating it; the table includes a base support on which are mounted rotatable elements which use the rotation of the table to cause linear vertical displacement of threaded posts which engage these elements and on which rests the top plate; hence, vertical displacement of the table top simultaneously follows the vertical displacement of the posts.

Abstract: The disclosure herein describes a joint consisting of three serially-interconnectable members each including a cut-away section; the volumes defined by the cut-away sections of the first and second are equal and L-shaped. These two members, once assembled, define a cut-away section, the volume of which is rectangular. The volume of the cut-away section of the third member which serves to interlock the three pieces together equals the sum of the said L-shaped volume and the rectangular volume. One application of the joint of the present invention is in furniture support structures such as tables, shelves or the like.