Abstract: Systems and methods create a graphical representation of a research map that allows performance of search functions using the nodes of the graphical representation. In one implementation, a system includes a processor and a memory. The memory stores instructions that cause the processor to receive a query for searching a document repository and run the query in the document repository. The processor stores the results of the query and the query as a root node in a research tree. The processor receives a filter for the results of the query. The processor stores the filter and the result list for the filter as a filter node connected to the root node of in the research tree. The processor receives a request to view a document from the result list for the filter and stores the request as a document node connected to the filter node. The processor then creates a display of a research map that includes the research tree.

Abstract: The invention is directed to a process for the anaerobic purification of waste water in an anaerobic reactor, said process comprising burning the biogas produced in the purification, in a gas-burner, using the hot gases obtained thereby for indirect heating of water in a hot water boiler, which boiler is connected with the reactor by means of a line between the gas head of the boiler and a compartment through which the waste water flows, such as a conditioning tank or the anaerobic reactor, which line ends underneath the water level in the said compartment at such a level that a pressure of between 0.25 and 3 m of water column is maintained in the gas head of the boiler, in which boiler steam is generated which enters the said compartment through the said line and heats the waste water, and wherein the said boiler is further provided with a valve to let off steam in case the amount of biogas is in excess of the amount needed to heat the waste water.

Abstract: The invention is directed to a process for the anaerobic purification of waste water in an anaerobic reactor, said process comprising burning the biogas produced in the purification, in a gas-burner, using the hot gases obtained thereby for indirect heating of water in a hot water boiler, which boiler is connected with the reactor by means of a line between the gas head of the boiler and a compartment through which the waste water flows, such as a conditioning tank or the anaerobic reactor, which line ends underneath the water level in the said compartment at such a level that a pressure of between 0.25 and 3 m of water column is maintained in the gas head of the boiler, in which boiler steam is generated which enters the said compartment through the said line and heats the waste water, and wherein the said boiler is further provided with a valve to let off steam in case the amount of biogas is in excess of the amount needed to heat the waste water.

Abstract: In a transmission system in which information is transmitted from a first device (2) to a second device (6) and vice versa, use is made of a first part (t0-t3) of a timeslot to transmit data from the first device (2) to the second device (6) and of a second part (t3-t4) of the timeslot to transmit data from the second device (6) to the first device (2). To obtain correct operation of the system, the second device (6) is synchronized to the first device (2). This is done using a phase locked loop (78) which locks on the signal present on the interconnection lines between the first device (2) and the second device (6). To ensure reliable synchronization, the second part of the timeslot (t3-t4) ends before the beginning (t5) of the first part of the next timeslot; and a rising edge is presented at the beginning (t5) of the first part of each new timeslot.

Abstract: A power supply circuit includes a line voltage forming circuit and a supply voltage forming circuit. The line voltage forming circuit forms a voltage that is proportional to a line voltage provided by a telecommunication line, and the supply voltage forming circuit forms a second voltage from the first voltage. A sensing circuit senses the telecommunication line and provides a sensor signal that is representative of the power provided by the telecommunication line. The line voltage forming circuit is controlled by the sensor signal such that the slope of a load line characteristic of the line voltage forming circuit is modified when the sensor signal is above a predetermined threshold signal. The load line characteristic defines an increase of the line voltage with an increase of the line current provided by the telecommunication line.

Abstract: A current distribution circuit for application in a communication device, such as a telephone subscriber circuit comprises a first current sinking branch, which is connected in parallel to a second current sinking branch. Both branches sink at least the DC current on the telephone line, whereas an excess current in the DC line is taken up by the second current sinking branch, which is provided with a current sinking transistor, whose collector/emitter voltage is relatively large. This leads to a reduced effectively needed chip area. The DC line-current can be measured by means of a low pass filter, preferable connected to a current mirror means.

Abstract: The invention provides an integrated amplifier whose gain factor is adjusted by means of an auxiliary amplifier . The gain factor is determined by the ratio of two on-chip resistors and by the ratio of the dimensions of transistors in long-tailed pair circuits in the signal amplifier to those of the transistors in the long-tailed pair circuit in the auxiliary amplifier. Both resistance ratios and ratios between complete circuits can be realised highly accurately in integrated circuits. As a result, the accuracy of the gain factor is great. In an embodiment of the invention the dimensions of the long-tailed pair circuits in the auxiliary amplifier and in the signal amplifier are the same. This achieves that if the adjusting voltages and adjusting currents of corresponding transistors in the long-tailed pair circuits are the same, the gain factor is over a large range independent of supply voltage and temperature.

Abstract: The terminating impedance can be set electrically to eliminate selection and installation of discrete components in order to meet network manager specifications. A control device such as an EEPROM is easily adjusted (programmed) to control circuits presenting a predetermined specified impedance to the communications line. The impedance is preferably formed by a switched capacitor filter in which ratios of capacitance rather than absolute values are easily obtained during manufacture of an IC. The DC termination value may be set separately from the AC impedance.

Abstract: A telephone set includes an anti-sidetone circuit formed by a feedback loop having a filter in the feedback path. The feedback loop output is substantially equal to the signal produced at the set connection terminals by the microphone. Preferably the filter is composed of two sub-filters connected in cascade, formed of switched capacitors in an integrated circuit. An EEPROM control circuit can be included to permit easy programming during manufacture, to match a selected transmission line impedance.