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61.
We propose an application of knowledge engineering in the problem of active supporting for a large mirror. To reduce calculating load and to shorten cycle time, we divide the system hierarchically into a managing central controller and many autonomous local controllers, and use reasoning instead of dynamical analysis. The reasoning is based upon pattern matchings between observed error pattern and test patterns in the knowledge base.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988. 相似文献
62.
Using the concept of bleaching in optical dating, a new index of sediment sample bleaching percentage (BLP‐2) was developed and applied to evaluate sand grain transport from riverine to deep‐marine environments. As bleached grains in modern sediments have no optically stimulated luminescence (OSL)/infrared stimulated luminescence (IRSL) signal, bleached and unbleached feldspar grains are distinguished by IRSL intensity. The BLP‐2 distribution of present deposits around the Kumano area, on the Pacific coast of central Japan, suggests that sand grains in surface turbidites obtained from the bottom of the Kumano Trough are of flood/storm origin rather than seismogenic origin. The distribution of BLP‐2 tentatively suggests sand grain erosion–transport–depositional processes; for example, origin and transport agencies of shelf sand, and influence of coastal erosion on the beach deposit. Although the present BLP analysis is not yet supported by a rigorous statistical test, it is useful to distinguish recent deposition and remobilization of sand grains. Furthermore, if the depositional age and the luminescence age of sand grains are accurately estimated, sand grain transport processes of old (late Quaternary) sediments may be estimated by the methodology similar to that of the present study. 相似文献
63.
This paper examines dioxin profiles in bottom sediments from Tokyo Bay, Japan using sedimentation dating based on 210Pb measurements and dioxin measurements based on particle size distributions. Dioxin concentrations in surface sediment ranged from 3.2 to 52 pg-TEQ g(-1), with the concentrations in the bay back and central region being higher than those at the front of the bay. The vertical dioxin concentration in sediment core samples showed peak levels from years 1962 to 1980, with the maximum being 110 pg-TEQ g(-1). Principal component analysis indicates that the main source of dioxins in bottom sediment from the back of bay are herbicides such as CNP, while in the front of bay atmospheric deposition due to incineration activities are responsible. Dioxins in bottom sediment were mainly found in the particles <75 microm in size. 相似文献
64.
65.
66.
Abstract: Se-bearing benjaminite and matildite are described from the polymetallic zone of the Ikuno deposits, Japan. The former is the first occurrence in Japan, and is from two separate veins, the Nanten and Daimaru, while the locality of the latter could not be specified. The empirical formulae of two benjaminites based on 22 atoms are (Ag2. 74Cu0. 24)Σ2. 98(Bi7. 00Sb0. 01)Σ7. 01(S10. 89Se1. 12)Σ12. 01 (Nanten) and (Ag2. 90Cu0. 10)Σ3. 00(Bi6. 74Pb0. 18Sb0. 07)Σ6. 99(S11. 68Se0.33)Σ12. 01 (Daimaru), leading to the validation of the formula Ag3Bi7S12 as the ideal one for benjaminite, and that of matildite based on 4 atoms is Ag1. 00Bi1. 00(S1. 78Se0. 22)Σ2. 00. These designate the substitution of Se for S in all of them, where Se is preferentially incorporated into these Ag-Bi sulphosalts. The unit-cell parameters of them and matildite are: a 13. 272, b 4. 037, c 20. 185 Å, and β 103. 16° (Daimaru), a 13. 270, b 4. 040, c 20. 273 Å, and β103. 17° (Nanten); and a 4. 0670, c 18. 996 Å, respectively. The products of Au-Ag mineralization in the Ikuno polymetallic vein-type deposits also occur as such Ag-Bi sulfosalts as benjaminite and matildite, in addition to pavonite, “treasurite derivative” and “electrum” with cassiterite in the polymetallic zone, and also do as “electrum”, acanthite, and pyrargyrite-proustite in the Au-Ag zone. The significant quantity of the Ag-Bi sulfosalts does not violate the zoning occupying the outermost part of the zonal distribution of ores in the deposits. 相似文献
67.
In Situ Measurement of the Lobate Ctenophore Bolinopsis Mikado (Moser) Abundance by the Video Recording System 总被引:1,自引:0,他引:1
A video recording system (VRS) with dark-field illumination was designed for continuous observation of the lobate ctenophore Bolinopsis mikado on spatial distribution, abundance and size distribution. In situ operation proved that the VRS was capable to discriminate B. mikado larger than 15 mm in total length at the towing speed around 0.5 m s–1. The VRS was useful to determine spatial distribution of B. mikado biomass, since it measured the abundance and size composition simultaneously. 相似文献
68.
This paper describes the water circulation in the Kuril Basin and its role in the formation and seasonal variation in intensity
of the large anticyclonic eddies which occur in the basin. Oceanographic data for the period June 1977 through June 1979 suggest
that these eddies develop in summer and decay in winter. In summer, the eddy development is associated with a deepening of
the isopycnals caused by the surface flow of the Soya Warm Current over the basin, and the deep advection of cold, less saline,
oxygen-rich water from Terpenia Bay and the eastern continental shelf of Sakhalin Island. In winter, the eddy decay is caused
by surface cooling and convective mixing downward of the warm, saline surface water, which causes the isopycnals to rise and
leads to an attenuation of the eddies. This combination of the summer influx of water into the region, and the fall and winter
cooling of the eddies leads to the annual variation in eddy intensity. 相似文献
69.
Back-arc rifting in the Okinawa Trough 总被引:1,自引:0,他引:1
Masaaki Kimura 《Marine and Petroleum Geology》1985,2(3):222-240
Geological and geophysical data reveal that the Okinawa Trough shows incipient continental rifting, and crustal separation started from about 2 Ma. The early extensional movements in the trough are probably of Miocene age. In addition to the Miocene phase, two main periods of extension are recognized: a Pleistocene phase between 1.9 and 0.5 Ma and the present day phase. During the stage short central rifts (Central Grabens) were formed. The opening however, may have occurred only in the southern part of the trough basin having an average half spreading rate of 2 cm yr?1 since Early Pleistocene time, producing its present width of several tens of kilometres. These activities were well represented by igneous intrusions, sedimentary facies and sedimentary structures in and around the Okinawa Trough. The width of the zone affected by back-arc extension (defined as Greater Okinawa Trough) is larger than the present Okinawa Trough, whose width is 200–250 km. The present form of the Greater Okinawa Trough started to form at the same time as that of the Okinawa Trough. 相似文献
70.
Long-term current measurements were carried out near the Soya Strait in the Okhotsk Sea during a period from February 1980 to September 1982. The data were divided into five segments, each being 150 days long, and the tidal ellipse parameters of major axis, minor axis, orientation, and phase for the four major constituents (M2, S2, K1 and O1 tides) were calculated at each segment. The major axis of the mean tidal ellipse averaged over five segments was 29.9 cm sec–1 for O1 tide, 28.3 cm sec–1 for K1 tide, 10.4 cm sec–1 for M2 tide, and 3.7 cm sec–1 for S2 tide. The phase and orientation of the tidal ellipse were much stable. But, the root mean square deviations of the major axis reached 20% of the mean values for all four constituents. The tidal currents estimated from the sea level records at Wakkanai and Esashi along the Hokkaido coast in the Okhotsk Sea show that their amplitudes and phases are in good agreement with the observed ones for all four constituents. 相似文献