Abstract: The present invention provides an apparatus for measuring the propagation velocity of a sound wave that may easily and accurately measure the propagation velocity of a sound wave in the horizontal and vertical directions of the sample by using the fixing unit preventing the measurement unit from vibrating and the distance measurement unit capable of accurately measuring the distance between the sound wave transmission and reception units, and a method of measuring the propagation velocity of a sound wave by using the apparatus.

Abstract: The present invention relates to a coring system and a determining method that can determine whether accurate coring was achieved. A coring system according to the present invention includes: a coring part with a core to be filled with an object to be cored; a driving unit controlling upward/downward movement of the coring part; a rope connecting the coring part with the driving unit; and a tensiometer measuring tension in the rope.

Abstract: A clinometer including a base plate and a compass which is mounted on the base plate and can measure a strike and a dip angle. The compass includes a first case which is rotationally provided on the base plate so as to move a strike scale indicated on the rim of the compass to a certain position and a second case which is provided in the first case, and which is fixed on the base plate so as to fix a dip scale indicated on the rim of the compass at a certain position.

Abstract: A geothermal power generation system using heat exchange between working gas and molten salt includes a heat collector. A plurality of molten salt containers is disposed in a heat transferor at predetermined intervals from each other. A heat exchanger transfers a heat source of the heat collector to the molten salt in the plurality of molten salt containers. The heat transferor is disposed in the ground. Working gas which receives the heat source of the molten salt via heat exchange enters and exits the heat transferor. A turbine unit is connected to the heat transferor, and generates mechanical energy using energy of the working gas. A power generating unit is connected to the turbine unit, and generates electrical energy using the mechanical energy.

Abstract: Provided is a sensor for measuring water levels of groundwater and surface water using magnetostriction displacement and multi measurement system for groundwater and surface water by using the same. The sensor includes an outer case having a hollow space therein and extending in a longitudinal direction, a magnetostriction line spaced apart from an inner wall in the hollow space of the outer case to extend in the longitudinal direction, a floating permanent magnet guided along the magnetostriction line to be movable in the longitudinal direction, the floating permanent magnet being changed in position to correspond to a water level; and a transceiver applying a current pulse into the magnetostriction line to receive an elastic wave that is generated while first magnetic fields formed in a circumferential direction of the magnetostriction line by the current pulse crosses a second magnetic fields formed in an axial direction of the magnetostriction line by the permanent magnet.

Abstract: Provided is an apparatus for a soil box experiment applying vertical vibration. The apparatus for the soil box experiment applying the vertical vibration includes: a soil box for realizing a slope on which landslide occurs, the soil box being inclinedly disposed and having an opened upper portion to accommodate soil therein, a base member disposed under the soil box to support the soil box, and a vibration unit disposed on the base member to vertically vibrate the soil box.

Abstract: Provided is a dry separation apparatus including: a main body; a first deck; a plurality of guides; a supply part; an air blow fan; and a vibration part. A dry separation method includes: supplying an object to be separated to a top surface of a first deck provided with a plurality of punches; sending, by an air blow fan, air to the punches (first punches); and horizontally vibrating, by a vibration part, the first deck so as to discharge particles which have different specific gravities of the object to be separated and a moveable force exerted by air passing the first punches through different passages.

Abstract: Provided is a method of measuring a change in the density of an underground material. To measure the change in the density of the underground material, a borehole is installed above a target underground material and a first gravimeter and a second gravimeter are installed outside and inside of the borehole, respectively. Sequentially, a change in the density of the target underground material is calculated based on a first gravitational change and a second gravitational change measured using the first gravimeter and the second gravimeter. According to the method, it is possible to precisely measure the change in the density of the target underground material, such as an oil, a gas, etc., stored in an underground reservoir and carbon dioxide injected into an underground storage.

Abstract: A method of analyzing a 3D geological structure using a structure index. The method includes the steps of estimating physical property values on common coordinates to calculate two or more physical property models on the same 3D grid (L×M×N); normalizing the physical property models, thus obtaining normalized physical property models which are then represented in a scatter plot of physical properties; converting distribution positions of the normalized physical property models on the scatter plot of physical properties into type angle (TA) and into type intensity (TI); determining a minimum of TI values, which classifies two or more classes on a scatter plot of the TA and TI values, to be a threshold; and analyzing the 3D geological structure based on a local extreme point and/or points in the scatter plot for the TA and TI using the threshold.

Abstract: The present invention relates to a lithium recovery device and recovery method. The lithium recovery device of the present invention includes: a first electrode; a second electrode; and a power supply device. In the lithium recovery device of the present invention, since lithium is attached to an adsorbent of the first electrode by applying a current to the first and second electrodes in a state in which the first and second electrodes are immersed in a lithium-containing fluid, the first electrode including a carrier made of a stainless steel material in a form of an iron mesh or perforated sheet and having a surface coated with the adsorbent containing a manganese oxide, and the second electrode facing the first electrode, it is possible to increase a size of the device and have excellent energy efficiency and economic feasibility.

Abstract: Disclosed is a method of preparing calcium carbonate using a direct carbonation reaction. The method includes dissolving fuel gas desulfurization gypsum into an ammonia solution, performing a filtering process after making a carbonation reaction by feeding carbon dioxide into the ammonia solution in which the fuel gas desulfurization gypsum is dissolved, and performing a filtering process after precipitating the calcium carbonate by maintaining a filtered solution in a stationary state.

Abstract: Disclosed is a method for verifying representativeness of samples collected in a contaminated soil. The method includes the steps of horizontally and vertically collecting the samples from the contaminated soil on a basis of a stratum of the contaminated soil at a predetermined sampling interval; measuring a total concentration of trace elements by analyzing the collected samples according to the sampling interval; and determining horizontal and vertical sampling intervals and a sample number based on a statistical analysis result for the total concentration of the trace elements.

Abstract: Disclosed herein is a test apparatus for early landslide detection fully-connected with pore water pressure, surface displacement and shear surface. The test apparatus calculates a factor of safety of a slope based on variation in pore water pressure, surface displacement and shear surface of a soil mass, and predicts a change in factor of safety, thus making early landslide detection possible. In the test apparatus, while a container of a slider is moved with a soil mass loaded into the container, shear surface and surface displacement environment is provided, and the shear strength and the shear stress of the soil mass can be calculated based on the pore water pressure and the weight of the soil mass. Thereby, the factor of safety of the soil mass can be calculated, and early landslide detection can be realized by using variation of the factor of safety of the slope.

Abstract: Provided is an apparatus for a soil box experiment making a shape of a variable landslide surface. The apparatus for the soil box experiment making the shape of the variable landslide surface includes a soil box for realizing a slope on which landslide occurs, the soil box being inclinedly disposed and having an opened upper portion to accommodate soil therein, a base member disposed under the soil box to support the soil box, and a shape changing unit for changing a shape of a bottom surface of the soil box.

Abstract: Provided is a particle separation apparatus. The particle separation apparatus for separating soil by particle size in a wet-type separation manner includes a body unit providing a space in which a mixture of the soil and water is received to flow vertically, a screen unit coupled to the inside of the body unit to separate the soil by the particle size from the mixture that flows vertically, and a space adjustment unit coupled to a lower portion of the body unit to cover the lower portion of the body unit, the space adjustment unit adjusting a volume of a lower space of the body unit to allow the mixture to repeatedly flow in a vertical direction.

Abstract: Disclosed is a method of recovering a rare earth element from oxidized scrap of permanent magnet. The method includes leaching an oxidized scrap of a permanent magnet from a sulfuric acid solution, and recovering the rare earth element after precipitating the rare earth element contained in the oxidized scrap of the permanent magnet by adding sodium sulfate into the sulfuric acid solution.

Abstract: Disclosed is a method of detoxifying asbestos of waste slate. The method includes concentrating the asbestos by introducing hydrochloric acid aqueous solution into waste slate powder to dissolve and remove a limestone component contained in the waste slate; and mixing the concentrated asbestos with oxalic acid and performing a low-temperature heat treatment. The waste slate is crushed and pulverized and powder of the crushed and pulverized waste slate is formed in a size in a range of 100 meshes to 300 meshes. The detoxified asbestos includes re-crystallized magnesium oxalate having a rhombohedral or amorphous shape.

Abstract: The present invention relates to an apparatus and method of preparing a reference solution of a gaseous substance necessary for calibration of various measuring instruments used in measurement of the gaseous substance, such as radon (Rn-220) or a volatile substance, contained in seawater, subsurface water, surface water or the like. An apparatus of preparing a reference solution according to the present invention includes a gas component detector having two ports and configured to measure a concentration of a predetermined gaseous substance; a gas vessel having two ports and configured to accommodate the predetermined gaseous substance; a reference solution preparation vessel having two ports and configured to accommodate a predetermined liquid substance; pipe lines connecting the ports of the gas component detector, the gas vessel and the reference solution preparation vessel; and valves installed on the pipe lines.

Abstract: The present invention relates to an apparatus and method of measuring effective porosity of various media such as rock or soil using radon that is an inert gas. An apparatus of measuring porosity according to the present invention includes: a gas component detector having two ports and configured to measure a concentration of a predetermined gas; a gas vessel having two ports and configured to accommodate the predetermined gas; a medium vessel having two ports and configured to accommodate a medium, of which the porosity is desirous to be measured; pipe lines connecting the ports of the gas component detector, the gas vessel and the medium vessel; and valves installed on the pipe lines.

Abstract: The present invention relates to a leaching method of rare-earth metals using a hydrochloric acid from a manganese nodule, and more particularly, to a leaching method of rare-earth metals using a hydrochloric acid from a manganese nodule, in which a manganese nodule is mixed with a hydrochloric acid, then stirred and heated to leach the rare-earth metal included in the manganese nodule.