Abstract: A dual-mode tablet and a detecting and switching method for input signals thereof are provided. The dual-mode tablet includes an electromagnetic induction module and a touch input module. The microprocessor controls the electromagnetic induction module to electronically connect to an induction coil group and detects whether any electromagnetic signal is received. After the electromagnetic induction module receives one electromagnetic signal completely, the microprocessor controls the touch input module to electronically connect to the induction coil group. When the microprocessor receives a touch input signal, the microprocessor alternately controls one of the electromagnetic induction module and the touch input module to electronically connect to the induction coil group. When the microprocessor detects one electromagnetic signal is received, the electromagnetic induction module electronically connects to the induction coil group continuously until the electromagnetic signal is received completely.

Abstract: An optical input device is applied in an electronic device. The optical input device includes a light source generator and a photosensitive plate. The light source generator has a body and a light source disposed within the body. The photosensitive plate is electrically connected to the electronic device, or is electrically disposed within the electronic device, and is electrically connected to a microprocessor. The light source of the light source generator emits a light ray through the body to form a light pattern image on the photosensitive plate. The photosensitive plate detects a deformation of the light pattern image, and outputs a control signal to the microprocessor correspondingly according to a shape of the light pattern image, enabling the electronic device to execute a corresponding preset function.

Abstract: An apparatus of measuring concentration of wastewater is provided for determining discharge rate of wastewater from a wastewater-collecting tank. The apparatus includes a mixing tank, a measuring tank, a water supply unit, a wastewater supply unit, a concentration detector, a controller, and a monitor. The measuring tank is communicated with the mixing tank, and the water supply unit is communicated with the mixing tank. Further, the concentration detector is located in the measuring tank, the controller is electronically connected respectively with all other devices, and the monitor is electronically connected with the controller to show the operating status of every device. The apparatus is capable of measuring real concentration of wastewater in the wastewater-collecting tank, and results of which can be used to adjust the discharge rate from the wastewater-collecting tank within a safe range.

Abstract: A cleaning system that includes a cleaning device, a pipeline having a first end, a valve connected between the cleaning device and a second end of the pipeline to enable water flow from the pipeline to the cleaning device when the valve is held at an open position, a limit switch connected to the valve for providing a signal in response to a position of the valve, a controller electrically coupled to the limit switch to receive the signal, and a monitor electrically connected to the controller and operating in response to the signal.