Abstract: Disclosed are a photoacid generator, a photoresist composition including the same, and a method of preparing the photoacid generator. The photoacid generator may include a compound represented by Formula 1: wherein, in Formula 1, CY, A1, A2, and B are respectively described in the specification.

Abstract: An exhaust gas recirculation system of an internal combustion engine where a cylinder head having an intake port and an exhaust port is coupled to a cylinder block, and a portion of an exhaust gas exhausted from the exhaust port is flowed into the intake port through a control valve, may include a recirculation gas gallery integrally formed at the cylinder head and communicated with the intake port, a control valve assembly including the control valve and communicated with the recirculation gas gallery, and at least a recirculation gas extracting unit that is communicated with the control valve assembly and the exhaust port.

Abstract: An exhaust gas recirculation system of an internal combustion engine where a cylinder head having an intake port and an exhaust port is coupled to a cylinder block, and a portion of an exhaust gas exhausted from the exhaust port is flowed into the intake port through a control valve, may include a recirculation gas gallery integrally formed at the cylinder head and communicated with the intake port, a control valve assembly including the control valve and communicated with the recirculation gas gallery, and at least a recirculation gas extracting unit that is communicated with the control valve assembly and the exhaust port.

Abstract: An exhaust gas recirculation system. A water jacket in a cylinder block is configured for coolant to flow therein. A cylinder head is attached to the cylinder block. A cylinder is disposed in the cylinder block and the cylinder head. An intake manifold runner is connected to an intake hole of the cylinder. An exhaust manifold runner is connected to an exhaust hole of the cylinder. A first recirculation gas pathway is disposed in the cylinder block, and receives recirculated exhaust gas from the exhaust manifold runner. A second recirculation gas pathway is disposed in the cylinder head, and has a first end connected to the first recirculation gas pathway and a second end connected to the intake manifold runner. A recirculation valve, mounted at the second recirculation gas pathway, controls supply of the recirculated exhaust gas to the intake manifold runner. An engine control unit controls the recirculation valve.

Abstract: An exhaust gas recirculation system. A water jacket in a cylinder block is configured for coolant to flow therein. A cylinder head is attached to the cylinder block. A cylinder is disposed in the cylinder block and the cylinder head. An intake manifold runner is connected to an intake hole of the cylinder. An exhaust manifold runner is connected to an exhaust hole of the cylinder. A first recirculation gas pathway is disposed in the cylinder block, and receives recirculated exhaust gas from the exhaust manifold runner. A second recirculation gas pathway is disposed in the cylinder head, and has a first end connected to the first recirculation gas pathway and a second end connected to the intake manifold runner. A recirculation valve, mounted at the second recirculation gas pathway, controls supply of the recirculated exhaust gas to the intake manifold runner. An engine control unit controls the recirculation valve.