Abstract: Solid fine particles which contain a magnesium atom, an aluminum atom and a C1-20 alkoxy group simultaneously, are insoluble in a hydrocarbon solvent, and have an average particle diameter of 3 to 80 ?m, and an olefin polymerization catalyst containing the solid fine particles and a transition metal compound in the groups 3 to 11 in the periodic table, exhibit a very high olefin polymerization activity without combination with an expensive organoaluminum oxy compound or organoboron compound and maintains a high activity in polymerization for a long time, and an olefin polymer excellent in powdery properties can be produced by using the olefin polymerization catalyst. The transition metal compound in the groups 3 to 11 in the periodic table includes a transition metal compound having a ligand containing two or more atoms selected from a boron atom, a nitrogen atom, an oxygen atom, a phosphorus atom and a sulfur atom.

Abstract: An ethylene-based polymer which is an ethylene/C4 to C10 ?-olefin copolymer and satisfies the following requirements [k1] to [k3]: [k1] melt flow rate (MFR) under a loading of 2.16 kg at 190° C. is in the range of 1.0 to 50 g/10 minutes; [k2] LNR defined as a scale of neck-in upon film molding is in the range of 0.6 to 1.4; and [k3] take-up speed at break [DS (m/min)] at 160° C. and melt flow rate (MFR) satisfy the following relationship (Eq-1): 12×MFR0.577?DS?165×MFR0.577 (Eq-1), and a thermoplastic resin composition containing the ethylene-based polymer, provide a molded product, preferably a film, excellent in moldability and mechanical strength.

Abstract: A drive circuit for a power semiconductor device includes: a sampling signal generating circuit for detecting that an input control signal instructs OFF and outputting a sampling signal at the time instant of start of a Miller period of time of an IGBT; a gate voltage detecting circuit for detecting a Miller voltage of the IGBT at the timing when the sampling signal is inputted and outputting, when the Miller voltage is equal to or larger than a threshold, an over-current detection signal; and a gate voltage controlling circuit for controlling, in response to the over-current detection signal, a gate voltage of the IGBT in such a way that the IGBT is turned OFF at slower speed than in the normal state. Thus, it is possible to suppress a surge voltage which is generated when the IGBT is turned OFF during the flow of an over-current.

Abstract: A drive circuit includes a gate voltage detector that detects a gate-emitter voltage Vge that appears between the gate and emitter of a power semiconductor device throughout a detection time period during which a sampler allows the process of detecting the gate-emitter voltage Vge, and that recognizes the occurrence of an abnormality in the power semiconductor device when the gate-emitter voltage Vge exceeds a reference value. Therefore, the drive circuit can protect the power semiconductor device with higher reliability by promptly detecting the occurrence of a short circuit even when the power semiconductor device is resistant to high voltages.

Abstract: A novel olefin polymerization catalyst is provided which comprises (A) a transition metal compound or lanthanoid compound containing two or more atoms selected from the group consisting of boron, nitrogen, oxygen, phosphorus, sulfur, and selenium; and (B) a Lewis acid. A process for producing an olefin polymer is also provided. The catalyst has a high olefin polymerization activity without a combined use of an expensive organoaluminum oxy-compound or organoboron compound, and can maintain the high activity for a long polymerization time.

Abstract: A drive circuit includes a gate voltage detector that detects a gate-emitter voltage Vge that appears between the gate and emitter of a power semiconductor device throughout a detection time period during which a sampler allows the process of detecting the gate-emitter voltage Vge, and that recognizes the occurrence of an abnormality in the power semiconductor device when the gate-emitter voltage Vge exceeds a reference value. Therefore, the drive circuit can protect the power semiconductor device with higher reliability by promptly detecting the occurrence of a short circuit even when the power semiconductor device is resistant to high voltages.

Abstract: A drive circuit for a power semiconductor device includes: a sampling signal generating circuit for detecting that an input control signal instructs OFF and outputting a sampling signal at the time instant of start of a Miller period of time of an IGBT; a gate voltage detecting circuit for detecting a Miller voltage of the IGBE at the timing when the sampling signal is inputted and outputting, when the Miller voltage is equal to or larger than a threshold, an over-current detection signal; and a gate voltage controlling circuit for controlling, in response to the over-current detection signal, a gate voltage of the IGBT in such a way that the IGBT is turned OFF at slower speed than in the normal state. Thus, it is possible to suppress a surge voltage which is generated when the IGBT is turned OFF during the flow of an over-current.

Abstract: Contents on a server that need not be updated for a fixed period of time are recorded directly in a medium, and desired contents in a local device can be accessed by the same operation procedure as that for accessing the server storing the contents. When a request to acquire delivery information is made from information browsing unit with respect to a local proxy server, the local proxy server analyzes the request, and acquires a server-side control file managed by a server with respect to which 10 the request has been made, and a local-side control file in duplicate information storing unit. If corresponding information exists in the duplicate information storing means and also if the information has the latest version number, the information is fetched from the duplicate information storing unit; otherwise the delivery information is fetched from a server computer.

Abstract: Contents on a server that need not be updated for a fixed period of time are recorded directly in a medium, and desired contents in a local device can be accessed by the same operation procedure as that for accessing the server storing the contents. When a request to acquire delivery information is made from information browsing unit with respect to a local proxy server, the local proxy server analyzes the request, and acquires a server-side control file managed by a server with respect to which the request has been made, and a local-side control file in duplicate information storing unit. If corresponding information exists in the duplicate information storing means and also if the information has the latest version number, the information is fetched from the duplicate information storing unit; otherwise the delivery information is fetched from a server computer.

Abstract: A novel olefin polymerization catalyst is provided which comprises (A) a transition metal compound or lanthanoid compound containing two or more atoms selected from the group consisting of boron, nitrogen, oxygen, phosphorus, sulfur, and selenium; and (B) a Lewis acid. A process for producing an olefin polymer is also provided. The catalyst has a high olefin polymerization activity without a combined use of an expensive organoaluminum oxy-compound or organoboron compound, and can maintain the high activity for a long polymerization time.

Abstract: Disclosed is a solid titanium catalyst component for olefin polymerization comprising magnesium, titanium, halogen, and (C) a phthalic diester represented by the following structural formula (i): ##STR1## wherein R is a branched hydrocarbon group of 7 carbon atoms, and two or R may be the same as or different from each other. Also disclosed are a process for preparing the solid titanium catalyst component, an olefin polymerization catalyst containing said solid titanium catalyst component and a process for olefin polymerization using the olefin polymerization catalyst. According to the present invention, the olefin polymer having high stereoregularity can be produced in a prominently high yield per catalyst unit.