Abstract: The present invention relates to the technical field of mine fire prevention and extinguishing, in particular to a liquid nitrogen direct injection and low-temperature foaming intelligent filling system based on mine fire area characteristics and an application method, comprising a liquid nitrogen storage tank, a liquid nitrogen direct injection system and a low-temperature foaming system, wherein the liquid nitrogen storage tank communicates with a liquid nitrogen pressurizing device through a main pipeline; a temperature control unit is arranged on the main pipeline; and the liquid nitrogen pressurizing device is connected with the liquid nitrogen direct injection system and the low-temperature foaming system, respectively, liquid nitrogen is directly injected into a foam liquid, to prepare a low-temperature foam type fire preventing and extinguishing material by means of forced convection, membrane boiling, explosion boiling and nucleate boiling between the liquid nitrogen and water.

Abstract: A warning device (100, 212, 301, 302, 510) for use in a luminaire (201, 410, 501), comprising a housing (110, 210, 310) accommodating a drive module (115, 215, 401, 402, 520) arranged to be coupled to a luminaire and to a mains voltage (260, 560). The drive module comprises a light source (120, 420) coupled to a switch (180, 380, 491, 492) and an electrical interface (140, 240) configured to electrically connect the drive module and the mains voltage to a light element (530) of the luminaire. The housing comprises a lid (130, 230, 330) operably coupled to the switch of the drive module and configured to activate the switch upon an opening of the lid for switching on the light source upon a current of the mains voltage passing in the electrical interface and deactivate the switch module upon a closing of the lid for switching off the light source.

Abstract: The present disclosure relates to a conditional branch coverage calculation method and device, computer apparatus, storage medium and computer program product. The method includes: acquiring code types of uncovered conditional branch code lines in target code, and acquiring comment information corresponding to the uncovered conditional branch code lines according to the code type; acquiring coverage parameter corresponding to the uncovered conditional branch code lines according to the comment information corresponding to the uncovered conditional branch code lines; and calculating a conditional branch coverage corresponding to the target code according to the coverage parameters corresponding to the uncovered conditional branch code lines and a total number of conditional branch code lines in the target code.

Abstract: A warning device (100, 212, 301, 302, 510) for use in a luminaire (201, 410, 501), comprising a housing (110, 210, 310) accommodating a drive module (115, 215, 401, 402, 520) arranged to be coupled to a luminaire and to a mains voltage (260, 560). The drive module comprises a light source (120, 420) coupled to a switch (180, 380, 491, 492) and an electrical interface (140, 240) configured to electrically connect the drive module and the mains voltage to a light element (530) of the luminaire. The housing comprises a lid (130, 230, 330) operably coupled to the switch of the drive module and configured to activate the switch upon an opening of the lid for switching on the light source upon a current of the mains voltage passing in the electrical interface and deactivate the switch module upon a closing of the lid for switching off the light source.

Abstract: An LED driver, comprising: an inductive switch mode converter having an inductive component (16,22), an LED output (30) for an LED load and a main converter switch (18) for controlling a current flowing through the inductive component; a sensor (32) for generating a sensor signal indicative of the output current or voltage provided to the LED output; a feedback element (34) which provides a feedback path for feeding back the sensor signal for control of the main converter switch (18); and a processing circuit (50) for processing the sensor signal which has been fed back, wherein the processing circuit is adapted to generate an output when there is no sensor signal so as to limit the current flowing through the main converter switch when no sensor signal is present.

Abstract: An LED driver, comprising: an inductive switch mode converter having an inductive component (16,22), an LED output (30) for an LED load and a main converter switch (18) for controlling a current flowing through the inductive component; a sensor (32) for generating a sensor signal indicative of the output current or voltage provided to the LED output; a feedback element (34) which provides a feedback path for feeding back the sensor signal for control of the main converter switch (18); and a processing circuit (50) for processing the sensor signal which has been fed back, wherein the processing circuit is adapted to generate an output when there is no sensor signal so as to limit the current flowing through the main converter switch when no sensor signal is present.

Abstract: Proposed is a device management apparatus and method for use in a device management network including a remote device management system. The device management apparatus comprises a communication interface (6) adapted to receive device management commands of differing nature from the remote device management system and to transmit a feedback signal to said remote device management system if requested by said device management commands, wherein the differing nature of a device management command comprises a differing level of power required to process the device management command, wherein the differing level of power required to process the device management command further relates to whether or not the device management command requires the communication interface (6) to transmit the feedback signal.

Abstract: A DC-DC converter has a pulse width control circuit producing a sequence of pulses, with an on time, an off time and a switching frequency. The on time as well as the switching frequency are both varied in dependence on a dimming setting.

Abstract: Proposed is a device management apparatus and method for use in a device management network including a remote device management system. The device management apparatus comprises a communication interface (6) adapted to receive device management commands of differing nature from the remote device management system and to transmit a feedback signal to said remote device management system if requested by said device management commands, wherein the differing nature of a device management command comprises a differing level of power required to process the device management command, wherein the differing level of power required to process the device management command further relates to whether or not the device management command requires the communication interface (6) to transmit the feedback signal.

Abstract: A DC-DC converter has a pulse width control circuit producing a sequence of pulses, with an on time, an off time and a switching frequency. The on time as well as the switching frequency are both varied in dependence on a dimming setting.