[en] The present invention provides a method of and a device for burning radioactive activated carbon and other radioactive wastes discharged from a radioactive material handling facility. Namely, finely powdered radioactive activated carbon is subjected to a burning treatment by an activated carbon burner in a preheater. The combustion gas generated at that time is supplied to an incinerator for other radioactive wastes to burn other radioactive wastes. Excess air can be supplied in such a device upon burning the radioactive activated carbon by a burner in the preheater. Therefore, radioactive activated carbon in an insufficient burning state can also be burnt completely in the incinerator. Accordingly, ashes devolumed in the burning treatment have only to be stored by filling them in a drum. As a result, the space for the storage can greatly be decreased. Since the burner for the activated carbon is in the preheater, the amount of auxiliary fuels to be used in the preheater can be saved. (I.S.)

[en] The pressure in a vessel containing radioactive wastes is previously reduced and cement mortar prepared by kneading cement, sand and kneading agent with water is poured under shaking substantially to the upper end of the vessel. After the lowering of the mortar level due to the deforming has been terminated, the pressure is increased gradually. Then, the cement mortar is further poured substantially to the upper end of the vessel again. With such a two step pouring method, spaces other than the radioactive wastes in the vessel can be filled substantially completely with the cement mortar. Accordingly, it is possible to avoid the problem in view of the strength due to the formation of gaps at the inside of the vessel, or leaching of radioactive materials due to the intrusion of water into the gaps. Further, if washing water is reutilized as water for kneading or washing after the precipitation of the solid contents, the amount of the secondary wastes generated can be reduced. (T.M.)

[en] The present invention provides a method of and a device for automatically identifying the number on the upper surface of a fuel of a fuel assembly in a PWR type reactor. Namely, the number on the upper surface of the fuel assembly of the PWR is not arranged in a row, but indent letters are dispersed to predetermined positions of the surface to be indented. Accordingly, the identification of letters is difficult. In the present invention, the letters are identified by the following procedures. Procedure (1): the letters are detected while having a corner portion of the upper surface of a fuel assembly where the number is indented as characteristic points. A procedure (2): a letter region is determined to a relative position based on the characteristic points while determining indent letters having the same direction as one group. A procedure (3): a letter identification treatment is applied to the letter images in the above-mentioned letter region to identify them. A neural network is used for the letter identification treatment. (N.H.)

[en] The present invention always detects an abnormality of a plant at high accuracy irrespective of operation states of a plant. That is, various sensors are disposed at various portions in the plant for detecting abnormalities. A system for intaking plant operation states during plant operation on on-line is disposed in an abnormality detecting device independent of them. States of sound, temperature and vibration of the plant detected by each of the sensors are memorized corresponding to the plant operation states determined on on-line, so that detection of plant abnormality is corresponder to the plant operation states. Namely, an imaginary model for each of the sensors is provided, and the states of actual plant and signals from various kinds of sensors are compared with the plant operation state and signals of various sensors determined based on the imaginary model. If any contradiction occurs in the comparison, it is judged that abnormality is caused in the plant. (I.S.)

[en] The photodoping process in Al/AsS₂/Ag tri-layer films has been studied through measurements of electrical impedance, photodoped-layer thickness, and photocurrent. Frequency dependence of the impedance suggests that the sample under photodoping can be approximated by an equivalent electrical circuit. A thickness of photodoped layers, which is estimated from the impedance, is in agreement with a geometrical thickness measured by an atomic force microscope for chemically etched samples. Under the photodoping (with zero bias voltages), a photocurrent remains constant at ∼ 5 pA, and near the completion it increases to ∼ 1 nA, which is followed with a gradual decrease. By applying a bias voltage between the top (semi-transparent Al) and bottom (Ag) electrodes, we can change a photodoping rate by an order. This rate change is attributable to the modulation of an effective electric field in the doped layer, which induces the motion of Ag ions.

[en] The present invention provides a system for remote diagnosis of facilities disposed to not accessible places and for confirming a state of the inside of closed chambers upon occurrence of abnormality. Namely, a flying type monitoring robot is used as a monitoring means. When monitoring the inside of a closed vessel in the plant, a mechanism for securing the flying type monitoring robot secured to the chamber can be released from outside of the chamber. Then, when abnormality should occur in the chamber, the condition can be confirmed from various view points by remote operation. In addition, if the securing mechanism is released by alarm signals of a different plant monitoring system, influences of abnormality occurred in a different plant applied to the closed chamber can be confirmed, and presence or absence of abnormality can be monitored by remote operation. In addition, when an automatic navigation system is loaded on the flying type monitoring robot, the securing mechanism can be released by alarm signals of the different plant monitoring system in addition to the robot can stand-by while hovering at a predetermined place and fly to a place to be assumed as abnormal under automatic control. (I.S.)

[en] The present invention provides a method of and a device for automatically identifying fuel numbers impressed on fuel assemblies disposed in a fuel reprocessing facility, power plant and a reactor core at a high speed and at a high identification rate. Namely, three or more character images are photographed for one fuel assembly as an object of the identification under different illumination conditions. As a result, different character images by the number of the illumination directions can be obtained for identical impressed characters. Learning on a neural network system is applied to the images of all of the characters impressed on the fuel assembly obtained under illumination of predetermined directions. Then, result of the identification by the number of the illumination directions can be obtained for each of the characters as an object of the identification. As a result, since the result of the identification is determined based on a theory of decision of majority, highly automatic identification can be realized. (I.S.)

[en] The cerebral cortex of non-human primates has been divided, mainly by anatomical techniques, into an enormous number of areas. We are looking forward to a PET scanner designed for non-human primates, with a hope to determine active brain regions when the animal does various cognitive tasks. This measurement with PET can be combined with single cell recordings and anatomical tracer studies in non-human primates. Another big hope is to detect a change of active regions as the learning advances. (author)

[en] The nuclear power plants in Japan reach to 49 plants and supply 41.19 million kW in their installed capacities, which is equal to about 31% of total electric power generation and has occupied an important situation as a stable energy supplying source. As an aim to keeping safe operation and working rate of the power plants, various monitoring support systems using computer technology, optical information technology and robot technology each advanced rapidly in recent year have been developed to apply to the actual plants for a plant state monitoring system of operators in normal operation. Furthermore, introduction of the emergent support system supposed on accidental formation of abnormal state of the power plants is also investigated. In this paper, as a monitoring system in the recent nuclear power plants, design of control panel of recent central control room, introduction to its actual plant and monitoring support system in development were described in viewpoints of improvement of human interface, upgrade of sensor and signal processing techniques, and promotion of information service technique. And, trend of research and development of portable miniature detector and emergent monitoring support system are also introduced in a viewpoint of labor saving and upgrade of the operating field. (G.K.)

[en] An automated patrol-type monitoring and inspection system was developed and applied in a nuclear power plant. This system consists of a monorail, a monitoring robot and an operator's console. The monitoring robot consists of a sensor unit and a control unit. Three kinds of sensor, a color ITV camera, an infrared camera and a microphone are installed in the sensor unit. The features of this monitoring robot are; (1) Weights 15 kg with a cross-sectional dimensions of 152 mm width and 290 mm height. (2) Several automatic monitoring functions are installed using image processing and frequency analysis for three sensor signals. (author)