Abstract: Disclosed is a laser doppler velocity system that can easily change a focal length of laser beam, in order to measure the velocity of fluid. As the fluid lens is used in order to focus the laser beam, the lens aperture is rapidly and accurately changed at a low power to easily measure the flow-velocity and shear stress of the boundary layer of the structure within the flow field. As the optical array including the fluid lens is integrated using a diode laser as a laser light source, the laser doppler velocity system can be made in small-size. Also, as the laser doppler velocity system is inserted into the surface of the structure, it can be used as a surface flow field measurement sensor.

Abstract: A separable ball valve apparatus and ball valve assembly capable of selectively opening/closing a separable flow path are provided. The separable ball valve apparatus comprises a separable pipe member having a flow path through which fluid flows, a ball member having at least two balls disposed in the pipe member, opening and closing the flow path, and adjacent to each other, and an opening/closing member configured to control the ball member to open/close the flow path, wherein the balls have through-holes, respectively, and the opening/closing member includes a gear train configured to control the opening/closing of the at least two balls. Therefore, it is possible to simply open/close pipes having the flow path and detachably attach the pipes, increase space utilization due to removal of a separate coupling space for attachment/detachment of the pipes, and simultaneously open/close the two pipes, which are separated from each other through one operation.

Abstract: A coupling/decoupling assembly of a pipe which can selectively open/close a flow channel of the pipe is provided. In the coupling/decoupling assembly of the pipe, a first valve and a second valve are respectively joined with each end of a first pipe and a second pipe. A first driving axis and a second driving axis are respectively joined with each end of the first valve and the second valve. An outer surface and an inner surface of the first and second valves are formed in a spherical body, and the inner surface of the first valve and the outer surface of the second valve are overlapped with each other to close the flow channel of the pipe, and the inner surface of the first valve and the outer surface of the second valve having an identical radius of a curvature.

Abstract: A separable ball valve apparatus and ball valve assembly capable of selectively opening/closing a separable flow path are provided. The separable ball valve apparatus comprises a separable pipe member having a flow path through which fluid flows, a ball member having at least two balls disposed in the pipe member, opening and closing the flow path, and adjacent to each other, and an opening/closing member configured to control the ball member to open/close the flow path, wherein the balls have through-holes, respectively, and the opening/closing member includes a gear train configured to control the opening/closing of the at least two balls. Therefore, it is possible to simply open/close pipes having the flow path and detachably attach the pipes, increase space utilization due to removal of a separate coupling space for attachment/detachment of the pipes, and simultaneously open/close the two pipes, which are separated from each other through one operation.

Abstract: Disclosed is a laser doppler velocity system that can easily change a focal length of laser beam, in order to measure the velocity of fluid. As the fluid lens is used in order to focus the laser beam, the lens aperture is rapidly and accurately changed at a low power to easily measure the flow-velocity and shear stress of the boundary layer of the structure within the flow field. As the optical array including the fluid lens is integrated using a diode laser as a laser light source, the laser doppler velocity system can be made in small-size. Also, as the laser doppler velocity system is inserted into the surface of the structure, it can be used as a surface flow field measurement sensor.

Abstract: A method for real-time remote shopping using a real-time remote shopping system includes the steps of (a) obtaining the commodity information from a hand-held terminal and registering the information on a customer, (b) sending the shopping request information including the commodity information to a host server or a mobile terminal through the wired/wireless communication device, (c) receiving, at the mobile terminal, the shopping request information from the hand-held terminal or the host server, and sending the shopping data processed in real-time to the host server or the hand-held terminal, (d) receiving, at the hand-held terminal, the shopping data from the server or the hand-held terminal, and (e) sending, at the hand-held terminal, a shopping-ended signal to the host server or the hand-held terminal, and paying the price. The hand-held terminal includes a hand-held electronic device of the customer. The system and method can be applied to an internet shopping.

Abstract: A coupling/decoupling assembly of a pipe which can selectively open/close a flow channel of the pipe is provided. In the coupling/decoupling assembly of the pipe, a first valve and a second valve are respectively joined with each end of a first pipe and a second pipe. A first driving axis and a second driving axis are respectively joined with each end of the first valve and the second valve. An outer surface and an inner surface of the first and second valves are formed in a spherical body, and the inner surface of the first valve and the outer surface of the second valve are overlapped with each other to close the flow channel of the pipe, and the inner surface of the first valve and the outer surface of the second valve having an identical radius of a curvature.