Abstract: Provided is an underground environment change detection method including: repeatedly sensing an AC signal propagated through an underground in a magnetic induction manner; and monitoring an underground environment change from a change in the AC signal.

Abstract: A method of collecting samples that are not polluted at the outside of a borehole at a predetermined depth by using a multi-packer and an apparatus therefore. Contaminated water in the borehole between first and second packers of the multi-packer is selectively discharged into a contaminated water discharging vessel installed on a lower end of a sample collecting container by opening or closing an electronic switching valve in the contaminated water discharging vessel.

Abstract: Disclosed are a method of collecting samples and an apparatus thereof. The method of collecting a sample using a multi-packer includes (A) dropping a sample collecting container into a borehole to collect a sample; (B) confirming whether the dropped sample collecting container arrives at a predetermined depth; (C) allowing a first packer surrounding an outer portion of a top end of the sample collecting container and a second packer surrounding an outer portion of a bottom end of the sample collecting container to adhere closely to a wall of the borehole by expanding the first and second packers when the dropped sample collecting container arrives at the predetermined; (D) collecting the sample at an outside of a casing constituting the borehole; (E) separating the first and second packers from each other when the collecting of the sample is completed; and (F) retrieving the sample collecting container filled with the sample from the borehole.

Abstract: There is provided an automatic sequential sampler for roof-top runoff of rainwater, which comprises: a sensing part, a controlling part and a sampling part, and more particularly, which takes samples of rainwater, at regular intervals, by sensing whether it rains and controlling the rotation and stop of a sample bottle shelf in the sampling part, using a timer and a counter.

Abstract: There is provided an automatic sequential sampler for roof-top runoff of rainwater, which comprises: a sensing part, a controlling part and a sampling part, and more particularly, which takes samples of rainwater, at regular intervals, by sensing whether it rains and controlling the rotation and stop of a sample bottle shelf in the sampling part, using a timer and a counter.