Abstract: A syringe with retractable needle includes a hub, a barrel, and a plunger. The hub is provided with symmetrical retaining sections, and a hooking section of a predetermined length is formed at a front end of the plunger with a piston mounted the hooking section. The piston includes a diametrically larger front part and a diametrically smaller and deformable rear part. A top surface of the piston is tightly abutted on a large lower surface of the hooking section to prevent any bubble from existing behind the hooking section. When the plunger is fully pushed forward to compress the smaller rear part of the piston, the hooking section is brought to engage with the retaining sections on the hub, so that medical liquid is fully released from the barrel, and the hub and the needle thereof can be drawn into the barrel after the injection by pulling the plunger backward.

Abstract: A pump with a pressure driving head comprises a retaining tube; the retaining tube having a receiving space; liquid can flow therein; a returning element being installed in the receiving space; a movable tube received in the receiving space of the retaining tube; a head extending from a top of the movable tube; the head having an outlet which is communicated to the movable tube; when a pressure is applied to the head, the movable tube will move axially in the retaining tube; and an isolation device tightly adhered upon an inner wall of the receiving space of the retaining tube; an air isolation chamber being formed by the isolation device and the movable tube; with the pressing affect of the movable tube, a part of liquid in the retaining tube will be stored in the air isolation chamber so as to be formed with an air isolation layer.

Abstract: An energy generation device for mobile carriers is disclosed. The mobile carrier moves in a fluid environment. The disclosed device contains a rotating mechanical unit, a power generation unit, and a power storage unit. The rotating mechanical unit is connected to the surface of the mobile carrier, and is exposed in the fluid environment for converting the fluid kinetic energy into rotational energy. In addition, the power generation unit converts the rotational energy into electrical energy, which is then stored in the power storage unit.

Abstract: An energy generation device for mobile carriers is disclosed. The mobile carrier moves in a fluid environment. The disclosed device contains a rotating mechanical unit, a power generation unit, and a power storage unit. The rotating mechanical unit is connected to the surface of the mobile carrier, and is exposed in the fluid environment for converting the fluid kinetic energy into rotational energy. In addition, the power generation unit converts the rotational energy into electrical energy, which is then stored in the power storage unit.

Abstract: A traffic system is disclosed to include a passageway defining a moving direction and a vehicle mounted in the passageway and running along the moving direction. In one instance, the passageway has two inner side walls and an inner bottom wall having a transverse cross-section formed into a continuous smooth surface. In further a instance, there is provided with a buoyant fluid stored in the passageway for generating a buoyancy while displaced by the vehicle. A traffic method is also provided to include steps of providing a vehicle, providing a medium for carrying thereon the vehicle moving therealong, and providing a buoyant medium for reducing a weight of the vehicle.

Abstract: A traffic system is disclosed to include a passageway defining a moving direction and a vehicle mounted in the passageway and running along the moving direction. In one instance, the passageway has two inner side walls and an inner bottom wall having a transverse cross-section formed into a continuous smooth surface. In further a instance, there is provided with a buoyant fluid stored in the passageway for generating a buoyancy while displaced by the vehicle. A traffic method is also provided to include steps of providing a vehicle, providing a medium for carrying thereon the vehicle moving therealong, and providing a buoyant medium for reducing a weight of the vehicle.