Abstract: There is provided a network security device comprising: a processor programmed to: identify a terminal for which communication is to be blocked; detect Dynamic Host Configuration Protocol (DHCP) request information which is requesting a DHCP server to allocate an IP address; send out a message meaning that the IP address requested by the DHCP request information is unusable; and transmit, if the detected DHCP request information is sent by the identified terminal, DHCP release information for releasing the IP address requested by this DHCP request information to the DHCP server.

Abstract: An internal combustion engine, which can improve an annual energy consumption efficiency, is provided. A gas engine 1 includes: an oil cooler 11 having a passage via which heat is exchanged between engine cooling water and lubricating oil; and a control unit 12 configured to control a temperature of the engine cooling water to a constant temperature so as to cool the lubricating oil during high load operation and to heat the lubricating oil during low to medium load operation. The control unit 12 increases the temperature of the engine cooling water during low to medium load operation compared with the temperature of the engine cooling water during high load operation. An oil jet 18a, which is configured to inject the lubricating oil into a rear surface of a piston 17, is provided.

Abstract: A gas engine 1 which operates in stoichiometric mode under high-load conditions and which operates in lean burn mode under medium- and low-load conditions includes a valve 2 which supplies the gas engine 1 with an air-fuel mixture composed of air and fuel gas. In the valve 2, a valve unit 21 for stoichiometric operation is connected in series to a valve unit 22 for lean burn operation and is also connected to a mixer 24. An opening area of the valve 2 is controlled in such a manner as to ensure a predetermined opening area for effecting stoichiometric operation, to uniformly decrease the opening area over time until a switching operation from stoichiometric operation to lean burn operation ends, to ensure a predetermined opening area for effecting lean burn operation, and to uniformly increase the opening area over time until a switching operation from lean burn operation to stoichiometric operation ends.

Abstract: There is provided a network security device comprising: a processor programmed to: identify a terminal for which communication is to be blocked; detect Dynamic Host Configuration Protocol (DHCP) request information which is requesting a DHCP server to allocate an IP address; send out a message meaning that the IP address requested by the DHCP request information is unusable; and transmit, if the detected DHCP request information is sent by the identified terminal, DHCP release information for releasing the IP address requested by this DHCP request information to the DHCP server.

Abstract: An internal combustion engine, which can improve an annual energy consumption efficiency, is provided. A gas engine 1 includes: an oil cooler 11 having a passage via which heat is exchanged between engine cooling water and lubricating oil; and a control unit 12 configured to control a temperature of the engine cooling water to a constant temperature so as to cool the lubricating oil during high load operation and to heat the lubricating oil during low to medium load operation. The control unit 12 increases the temperature of the engine cooling water during low to medium load operation compared with the temperature of the engine cooling water during high load operation. An oil jet 18a, which is configured to inject the lubricating oil into a rear surface of a piston 17, is provided.

Abstract: An internal combustion engine is provided, which is capable of performing normal perturbation for a long period of time according to changes in a valve with time such as contamination, and wear. A gas engine 1 is configured to detect a stoichiometric air-fuel ratio by oxygen sensors 11 and 15 and to perform the perturbation using a solenoid valve 21. The gas engine 1 includes: an A/F valve 22 disposed in parallel with the solenoid valve 21; and a control unit 10. The control unit 10 controls to perform the perturbation in an intermediate region 21a of an opening/closing region of the solenoid valve 21 by detecting time deviations T1 and T2 of an air-fuel ratio that change due to the perturbation and by opening the A/F valve 22 according to the time deviations T1 and T2.

Abstract: A gas engine 1 which operates in stoichiometric mode under high-load conditions and which operates in lean burn mode under medium- and low-load conditions includes a valve 2 which supplies the gas engine 1 with an air-fuel mixture composed of air and fuel gas. In the valve 2, a valve unit 21 for stoichiometric operation is connected in series to a valve unit 22 for lean burn operation and is also connected to a mixer 24. An opening area of the valve 2 is controlled in such a manner as to ensure a predetermined opening area for effecting stoichiometric operation, to uniformly decrease the opening area over time until a switching operation from stoichiometric operation to lean burn operation ends, to ensure a predetermined opening area for effecting lean burn operation, and to uniformly increase the opening area over time until a switching operation from lean burn operation to stoichiometric operation ends.

Abstract: A challenge to be met by the present invention is to provide an electronic component mounting apparatus and an electronic component mounting method that enable a reduction in the frequency of operation required with switching of a component type, to thus enhance productivity.

Abstract: A challenge to be met by the present invention is to provide an electronic component mounting apparatus and an electronic component mounting method that enable a reduction in the frequency of operation required with switching of a component type, to thus enhance productivity.