Abstract: A wind power generation device capable of improving power generation efficiency is provided. The wind power generation device according to the present invention comprises: a substantially cylindrical duct 1 having a side wall with a substantially wing section; an impeller 2 rotatable around an axis of the duct 1; and a nacelle 5 that constitutes a streamlined pencil body 3 together with the impeller 2 and houses a generator 4 that uses torque of the impeller 2. The duct 1 has the side wall with the wing section so as to be able to produce a reduced pressure area at a rear of the duct and prevent generation of swirl at the rear of the duct 1. The pencil body 3 is provided so that a tip thereof is placed in the duct 1 and a rear end thereof protrudes from a rear end of the duct 1 so as to be close to a tip of the reduced pressure area produced at the rear of the duct 1. Blades 21 of the impeller 2 are provided in a maximum wind speed area 13 in the duct 1.

Abstract: The invention provides a wind power generator which can further improve a power generating efficiency. The wind power generator in accordance with the present invention is provided with an approximately cylindrical duct (10) with the side section thereof having a wing-like shape, an impeller (30) constructing a front end portion of a streamlined pencil body (20) coaxially installed with the duct and capable of rotating by a force of wind flowing in an inner portion of the duct (10), and a power generator (40) converting a rotational energy of the impeller (30) into an electric energy. A maximum wing thickness position (108) is positioned nearer a leading edge (102) than a center of a chord (106) in the side cross-sectional wing-like shape of the duct (10). Further, the chord (106) is tilted with respect to a duct axis in such a manner that an outer diameter of the duct (10) is made approximately uniform at least in a rear portion of the duct.

Abstract: A sensor is provided at the gateway of a local area network for successively acquiring IP packets passing through the gateway. The sensor detects various cracker attacks against the network based on the acquired IP packets. Information as to attacks detected by the sensor is given to a director which controls a firewall at the gateway of the network. Based on the given information, the director controls settings for the firewall to prevent IP packets associated with the detected attacks from entering the local area network.

Abstract: A wind power generation device capable of improving power generation efficiency is provided. The wind power generation device according to the present invention comprises: a substantially cylindrical duct 1 having a side wall with a substantially wing section; an impeller 2 rotatable around an axis of the duct 1; and a nacelle 5 that constitutes a streamlined pencil body 3 together with the impeller 2 and houses a generator 4 that uses torque of the impeller 2. The duct 1 has the side wall with the wing section so as to be able to produce a reduced pressure area at a rear of the duct and prevent generation of swirl at the rear of the duct 1. The pencil body 3 is provided so that a tip thereof is placed in the duct 1 and a rear end thereof protrudes from a rear end of the duct 1 so as to be close to a tip of the reduced pressure area produced at the rear of the duct 1. Blades 21 of the impeller 2 are provided in a maximum wind speed area 13 in the duct 1.

Abstract: For effecting cryptographic communications between entities i, j using a common cryptokey, each of the entities i, j generates a common cryptokey by applying an identifier transformation algorithm and a secret private key, which have previously been distributed from a center, to the identifier of the other entity with which to communicate (step 3). In a transmitting side, one-time pass cryptographic communication random number data are generated and encrypted by the common cryptokey, a plaintext is encrypted using the random number data, and the encrypted random number data and the encrypted plaintext are combined into an encrypted communication text (step 4). In a receiving side, the encrypted random number data in the encrypted communication text are decrypted using the common cryptokey, and the encrypted plaintext is decrypted using the decrypted random number data as a key (step 5).

Abstract: In a center, a Fourier transformation with a weighting function and a center matrix are applied to the identifier of each entity (steps 2-1, 2-2), which is then randomized by one-time pass random number data generated by a manual operation at each entity, thereby generating a secret private key peculiar to each entity (steps 2-3.about.2-5). The center also generates an identifier transformation algorithm based on the one-time pass random number data and the Fourier transformation with a weighting function (step 2-6). Thereafter, the center distributes the identifier transformation algorithm and the secret private key to each entity. Each entity applies the identifier transformation algorithm and the secret private key to the identifier of another entity with which to communicate, for thereby generating a common cryptokey for cryptographic communications between the entities.