A system for an aircraft includes a first fluid circuit extending from a first end to a second end, and a network comprising a plurality of networked heater assemblies disposed along the first fluid circuit between the first end and the second end. Each of the networked heater assemblies includes at least one temperature sensor, a heater element, and a local controller. The at least one temperature sensor is in communication with the first fluid circuit for periodically measuring a temperature in the first fluid circuit and generating a corresponding local temperature signal. The heater assembly selectively applies heat to the first fluid circuit based on the local temperature signal or another temperature signal on the network. The local controller receives the local temperature signal or another networked temperature signal and operates the heater assembly in response thereto to maintain the local temperature signal above a predetermined threshold.

The embodiments of the present disclosure disclose a refrigeration chip, a refrigeration system, and a sample testing system and method. The refrigeration chip is in contact with a low-temperature cold source, is used for refrigerating a sample, and comprises a heating layer and a heat conducting layer that are disposed in sequence. The heating layer comprises at least one temperature control unit that is disposed on the heat conducting layer; and the heat generated by the temperature control unit is transferred to the low-temperature cold source along the thickness direction of the heat conducting layer. The described technology enables a particular time period to be selected for refrigeration and thawing during the in-situ observation and representation of a sample, and refrigeration and heating rates higher than 105? C./s are attained by means of an interface thermal resistance design, thus ensuring that the sample is not damaged. The described technology is a significant improvement to operations related to the refrigeration, thawing, in-situ microscopic observation and so on of biological samples, and has great significance and broad application prospects.

Aspects of the present teachings describe a method and apparatus for automatically controlling a block temperature to reduce undershooting and overshooting of the temperatures of a sample contained in the block and participating in a polymerase chain reaction (PCR). The adaptive thermal block temperature control begins when a sample temperature enters a sample window region between a preliminary setpoint temperature and a target setpoint temperature for the sample. Based on thermodynamic behavior of the sample and the predetermined phase of PCR, predicting a time period measured subsequent to the preliminary setpoint temperature when the sample will reach the target setpoint suitable for the predetermined phase of PCR. During this time period, varying the block temperature ramp rate with a series of cooling and heating changes to ensure the block temperature reaches the target setpoint temperature at approximately the same time as the sample reaches the same. Synchronizing the block temperature and sample temperature to the target setpoint temperature reduces undershooting and overshooting of the sample temperature and increases the speed and efficiency of the overall PCR process as it relates to the thermal cycling operations.

Aspects of the present teachings describe a method and apparatus for automatically controlling a block temperature to reduce undershooting and overshooting of the temperatures of a sample contained in the block and participating in a polymerase chain reaction (PCR). The adaptive thermal block temperature control begins when a sample temperature enters a sample window region between a preliminary setpoint temperature and a target setpoint temperature for the sample. Based on thermodynamic behavior of the sample and the predetermined phase of PCR, predicting a time period measured subsequent to the preliminary setpoint temperature when the sample will reach the target setpoint suitable for the predetermined phase of PCR. During this time period, varying the block temperature ramp rate with a series of cooling and heating changes to ensure the block temperature reaches the target setpoint temperature at approximately the same time as the sample reaches the same. Synchronizing the block temperature and sample temperature to the target setpoint temperature reduces undershooting and overshooting of the sample temperature and increases the speed and efficiency of the overall PCR process as it relates to the thermal cycling operations.

A surge protection circuit for an electronic device such as an HVAC controller. In one example, the surge protection circuit may include a first voltage clamp, a second voltage clamp, a resistor, and an output port. The first voltage clamp may provide a first clamping voltage between a power input terminal and a common terminal. The second voltage clamp may provide a second clamping voltage that is less than the first clamping voltage. The resistor may be connected in series with the second voltage clamp, and the series connected resistor and second voltage clamp may be connected in parallel with the first voltage clamp. As such, a surge current at the power input terminal may be split between the first voltage clamp and the second voltage clamp. The amount of surge current that is provided to the second voltage clamp may be set by the value of the resistor.

A surge protection circuit for an electronic device such as an HVAC controller. In one example, the surge protection circuit may include a first voltage clamp, a second voltage clamp, a resistor, and an output port. The first voltage clamp may provide a first clamping voltage between a power input terminal and a common terminal. The second voltage clamp may provide a second clamping voltage that is less than the first clamping voltage. The resistor may be connected in series with the second voltage clamp, and the series connected resistor and second voltage clamp may be connected in parallel with the first voltage clamp. As such, a surge current at the power input terminal may be split between the first voltage clamp and the second voltage clamp. The amount of surge current that is provided to the second voltage clamp may be set by the value of the resistor.

A HVAC controller located within a building zone includes a housing, a wireless radio, a controller monitor, a temperature sensor, and a temperature compensation module. The wireless radio is contained within the housing and is configured to transmit data via a wireless HVAC network. The controller monitor is configured to detect wireless activity of the wireless radio, the wireless activity generating heat inside the housing and causing a temperature inside the housing to exceed a temperature of the building zone outside the housing. The temperature sensor is configured to measure the temperature inside the housing. The temperature compensation module is configured to determine a wireless heat rise resulting from the wireless activity, to calculate a temperature offset based on the wireless heat rise, and to determine the temperature of the building zone outside the housing by subtracting the temperature offset from the temperature measured inside the housing.

A HVAC controller located within a building zone includes a housing, a wireless radio, a controller monitor, a temperature sensor, and a temperature compensation module. The wireless radio is contained within the housing and is configured to transmit data via a wireless HVAC network. The controller monitor is configured to detect wireless activity of the wireless radio, the wireless activity generating heat inside the housing and causing a temperature inside the housing to exceed a temperature of the building zone outside the housing. The temperature sensor is configured to measure the temperature inside the housing. The temperature compensation module is configured to determine a wireless heat rise resulting from the wireless activity, to calculate a temperature offset based on the wireless heat rise, and to determine the temperature of the building zone outside the housing by subtracting the temperature offset from the temperature measured inside the housing.

A system for an aircraft includes a first fluid circuit extending from a first end to a second end, and a network comprising a plurality of networked heater assemblies disposed along the first fluid circuit between the first end and the second end. Each of the networked heater assemblies includes at least one temperature sensor, a heater element, and a local controller. The at least one temperature sensor is in communication with the first fluid circuit for periodically measuring a temperature in the first fluid circuit and generating a corresponding local temperature signal. The heater assembly selectively applies heat to the first fluid circuit based on the local temperature signal or another temperature signal on the network. The local controller receives the local temperature signal or another networked temperature signal and operates the heater assembly in response thereto to maintain the local temperature signal above a predetermined threshold.

A system for an aircraft includes a first fluid circuit extending from a first end to a second end, and a network comprising a plurality of networked heater assemblies disposed along the first fluid circuit between the first end and the second end. Each of the networked heater assemblies includes at least one temperature sensor, a heater element, and a local controller. The at least one temperature sensor is in communication with the first fluid circuit for periodically measuring a temperature in the first fluid circuit and generating a corresponding local temperature signal. The heater assembly selectively applies heat to the first fluid circuit based on the local temperature signal or another temperature signal on the network. The local controller receives the local temperature signal or another networked temperature signal and operates the heater assembly in response thereto to maintain the local temperature signal above a predetermined threshold.