One aspect of the invention provides an electric heater including: a resistive heating element; a current transformer positioned around a portion of the resistive heating element or a lead thereto, the current transformer adapted and configured to produce a secondary induced current proportional to a primary current flowing through the resistive heating element; and a controller communicatively coupled to the resistive heating element and the current transformer. The controller is programmed to either: (i): detect a deviation between the secondary induced current and a reference value; and in response to the deviation, generate an alert; or (ii) communicate to a remote server programmed to detect a deviation between the secondary induced current and a reference value.

A heat source simulation structure includes a heating body and a heating member to form a simulation heat source main body for conducting heat. The simulation heat source main body is enclosed in an outer case and a heating substrate with electrical insulation and heat insulation properties to avoid dissipation of the heat. The heating member is electrically connected with an external power supply for heating the heating body. A thermocouple member is disposed on the heating body corresponding to the heating member. A temperature monitoring port is connected with a data collection meter for recording the temperature of the heating body. By means of the heat insulation design enclosing the simulation heat source main body, the contact thermal resistance between the heating member and the heating body is reduced, further to lower the heat loss of the heat source simulation structure and enhance the measurement precision and reliability.

Provided is a power control device 100 comprising: a current detector 31 that measures a combined current value obtained by combining currents flowing through a plurality of loads 1-4; and an output calculation unit 11 that calculates a correction value obtained by dividing a total value of products of operation output values for the loads 1-4 and rated current values of the loads 1-4, respectively, by the combined current value obtained by the current detector 31, and that performs power supply control for the loads 1-4 on the basis of a corrected operation output value that is a product of the operation output value and the correction value for each of the loads 1-4, in which in a system that heats or cools a workpiece by means of a plurality of loads, heating control or cooling control can be performed in which an effect of a fluctuation in load characteristics is reduced.

An apparatus for calculating a thermal conductivity of a gaseous substance is provided. The apparatus includes a substrate; a cover member disposed on the substrate, wherein the cover member comprises a flow tunnel for the gaseous substance; a flow sensing element disposed on the substrate, wherein the flow sensing element is exposed to the gaseous substance in the flow tunnel; and a pressure sensing element disposed on the substrate, wherein the pressure sensing element is exposed to the gaseous substance in the flow tunnel.

A networked speaker device includes a sealed housing and an Ethernet port in the housing for receiving power and audio data from a network router via an Ethernet cable. A power supply subsystem in the housing manages the power received at the Ethernet port. A microprocessor subsystem, powered by the power supply subsystem, receives and processes the audio data to generate output audio signals. A digital audio amplifier, powered by the power supply subsystem, amplifies the output audio signals to drive a speaker driver to render an audio output. The device also includes at least one heater resistor in the housing powered by the power supply subsystem. The at least one heater resistor is controlled by the microprocessor subsystem to automatically heat the interior of the housing when temperature inside the housing falls below a given temperature.

The heating array includes first heating elements arranged in an elongated array, the first heating elements spanning from a first end to a second end of the elongated array, a midsection of each one of the first heating elements bowing concentrically outward from a radial centerline running longitudinally through the first end and the second end, the first heating elements being configured to flex concentrically inward when a hoop force is applied to sides of the elongated array.

A camera module includes a liquid lens including a first plate and an individual electrode disposed on a first surface of the first plate; a resistor disposed on the first surface of the first plate so as to be spaced apart from the individual electrode; and a temperature sensor connected to the resistor and configured to sense a temperature of the liquid lens and a heating controller connected to the resistor and configured to control a temperature of the liquid lens.

A substrate processing apparatus includes an AD converter configured to output digital values of a voltage applied to a heater resistor and a current flowing in the heater resistor; and a controller configured to control a temperature of the heater resistor by using a calculation voltage and a calculation current configured to calculate a resistance value of the heater resistor, which are obtained from an output result of the AD converter. The controller calculates at least one of the calculation voltage or the calculation current, based on a combination result of a digital signal obtained from the output result of the AD converter and a noise signal including a normal distribution noise.

A method of adjusting a watt density distribution of a resistive heater includes designing a baseline heater circuit. A detection circuit is designed having a constant trace watt density and the detection circuit overlaps the baseline heater circuit. The detection circuit is manufactured, and its baseline thermal map is obtained. The baseline heater circuit is manufactured, and a nominal thermal map is obtained. A subsequent detection circuit is manufactured, and an actual thermal map is obtained. A subtraction thermal image is created by subtracting the baseline thermal map from the actual thermal map, and a subsequent baseline heater circuit is modified according to the subtraction thermal image.

A specimen heating apparatus includes a heater unit configured to heat a test specimen held in a material testing machine, a heater holding unit configured to hold the heater unit in a set position relative to the test specimen for heating, a specimen temperature measurement unit attached to the heater unit and configured to measure temperature of the test specimen when the heater unit is in the set position, a temperature controller configured to control heating of the heater unit in response to a temperature measured by the specimen temperature measurement unit, and a thermal insulation unit configured to cover the heater unit, wherein the heater holding unit holds the heater unit in such a way that the heater unit is allowed to be brought to and removed from the set position while the test specimen is being held in the material testing machine.