A system and a method that utilizes wet proppants when creating fracturing fluid by receiving wet fracturing sand at a surge tank, vibrating the wet fracturing sand located within the surge tank, liquefying the wet fracturing sand within the surge tank based on the vibration, and metering the liquefied wet fracturing sand from the surge tank to a blending tub.

A control apparatus for an internal combustion engine detects an amount of particulate matter contained in an exhaust gas in an exhaust passage, according to an electrical property across electrodes of a particulate matter sensor disposed in the exhaust passage of the internal combustion engine. The term electrical property here refers to a property that changes with the amount of particulate matter deposited, for example, a current value of when a predetermined voltage is applied. After the internal combustion engine is started and detection of the amount of the particulate matter is completed, an element section of the particulate matter sensor is set to a predetermined temperature range. The particulate matter deposited on the element section is thereby burned and removed. The control apparatus maintains the element section in the predetermined temperature range after burning and removing the particulate matter until the internal combustion engine stops.

A system and a method that utilizes wet proppants when creating fracturing fluid by receiving wet fracturing sand at a surge tank, vibrating the wet fracturing sand located within the surge tank, liquefying the wet fracturing sand within the surge tank based on the vibration, and metering the liquefied wet fracturing sand from the surge tank to a blending tub.

A method for wirelessly controlling a working device using a handheld unit, the method comprising: connecting the working device to a central server by a network, wherein the working device is uniquely identified on the network by an assigned network address, and further wherein the working device and the central server are configured so that the central server can receive data concerning operation of the working device, and control operation of the working device, via the network; positioning a device-specific identification marker at the working device, wherein the device-specific identification marker is linked to the assigned network address of the working device; scanning the device-specific identification marker with the handheld unit, whereby to identify the working device and the assigned network address linked to the working device; and using the handheld unit to cause the central server to communicate with and control the working device at the assigned network address, whereby to allow the user to control operation of the working device via the handheld device and/or to receive data concerning the working device from the central server.

A monitoring system for a heating, ventilation, or air conditioning (HVAC) system of a residential or commercial building includes an evaporator unit device and four temperature sensors. The evaporator unit device includes an electrical sensor that measures current supplied to a circulator blower of the HVAC system. The measured current from the first electrical sensor is used to diagnose a problem with the circulator blower. The first temperature sensor that measures a temperature of refrigerant flowing between a condenser of the HVAC system and an expansion valve of the HVAC system. The second temperature sensor measures a temperature of refrigerant flowing between an evaporator and a compressor. The third temperature sensor measures a temperature of air flowing away from the evaporator. The fourth temperature sensor measures a temperature of air flowing toward the evaporator. The evaporator unit device transmits sensor data to a remote monitoring service over a data network.

A method for wirelessly controlling a working device using a handheld unit, the method comprising: connecting the working device to a central server by a network, wherein the working device is uniquely identified on the network by an assigned network address, and further wherein the working device and the central server are configured so that the central server can receive data concerning operation of the working device, and control operation of the working device, via the network; positioning a device-specific identification marker at the working device, wherein the device-specific identification marker is linked to the assigned network address of the working device; scanning the device-specific identification marker with the handheld unit, whereby to identify the working device and the assigned network address linked to the working device; and using the handheld unit to cause the central server to communicate with and control the working device at the assigned network address, whereby to allow the user to control operation of the working device via the handheld device and/or to receive data concerning the working device from the central server.

A monitoring system is disclosed for a heating, ventilation, or air conditioning (HVAC) system of a residential or commercial building. The monitoring system includes an evaporator unit device including a first current sensor that measures current supplied to a circulator blower. The measured current from the first current sensor is used to diagnose a problem with the circulator blower. The monitoring system includes a first temperature sensor that measures refrigerant temperature between a condenser and an expansion valve. The monitoring system includes a second temperature sensor that measures refrigerant temperature between an evaporator and a compressor. The monitoring system includes a condenser unit device that communicates with the evaporator unit device. The condenser unit device includes a second current sensor that measures current supplied to the compressor. The evaporator unit device transmits sensor data to a remote monitoring service over a data network.

An air filtration unit for withdrawing air from a room, purifying the withdrawn air, and then returning the purified air back into the room, the air filtration unit having: a housing configured to be mounted to a surface of the room; an air inlet formed in the housing; an air outlet formed in the housing; a passageway extending through the housing and connecting the air inlet to the air outlet; a filter disposed in the passageway for purifying the air in the passageway; and a suction fan disposed within the passageway for drawing air from the room into the air inlet through the filter and out of the air outlet to the room, whereby to capture at least one substance to the filter.

A mobile air-filtering isolation system, the system including a base; a frame extending upwardly from the base; an air filtration unit mounted to the frame; and at least one flexible curtain extending downward from the air filtration unit, whereby to form an enclosure.