Abstract: A differential absorption lidar includes: a light signal generation unit for generating first, second CW light signals with first, second wavelengths having different absorption coefficients with respect to a target, a light intensity modulation unit for subjecting the first, second CW light signal to intensity modulation with a first, second CW modulation signal having a first, second frequency in a baseband, a radiation unit for multiplexing the first, second CW light signals with the intensity modulated, forming the multiplexed light signals with two wavelengths in a predetermined beam size, and radiating the light signals, a reception unit for directly detecting scattered light from the target and converting the scattered light into an electrical signal, and a signal processing unit for extracting only the first, second frequency components from the electric signal, and detecting the concentration of the target from a difference in an amplitude of time wavelengths between two signals.

Abstract: A differential absorption lidar includes: a light signal generation unit for generating first, second CW light signals with first, second wavelengths having different absorption coefficients with respect to a target, a light intensity modulation unit for subjecting the first, second CW light signal to intensity modulation with a first, second CW modulation signal having a first, second frequency in a baseband, a radiation unit for multiplexing the first, second CW light signals with the intensity modulated, forming the multiplexed light signals with two wavelengths in a predetermined beam size, and radiating the light signals, a reception unit for directly detecting scattered light from the target and converting the scattered light into an electrical signal, and a signal processing unit for extracting only the first, second frequency components from the electric signal, and detecting the concentration of the target from a difference in an amplitude of time wavelengths between two signals.

Abstract: A parent unit is provided having: a precedent base for accumulating data from child units; an element data determination unit for processing the data into element data; an element data classification unit for creating a classification; an element data change classification unit for determining which classification the element data belongs to, and calculates transition probabilities among the classifications, and a display unit for displaying data. The child unit collects air current data, processes the data, obtains the transition probabilities, and calculates a probability of encountering air turbulence. The child unit then displays certain data when the probability of encountering air turbulence satisfies predetermined conditions.

Abstract: Embodiments of the present invention provide a small and well-characterized bulk acoustic wave device by fabricating a filter having a wide band width or a resonator having a wide oscillation frequency range together with a semiconductor circuit. In embodiments of the present invention, a bulk acoustic wave device comprises a semiconductor substrate having a dielectric substance layer thereon, the dielectric substance layer has a ground conductor layer thereon, the ground conductor layer has a piezoelectric ceramic thin film thereon and the piezoelectric ceramic thin film has a conductive electrode pattern thereon. The thickness of the piezoelectric ceramic thin film is more than ten times the thickness of the ground conductor layer, and the wave number of acoustic waves that propagate in a direction parallel to a surface of the piezoelectric ceramic thin film multiplied by the thickness of the piezoelectric ceramic thin film is less than 2.