EXPERIMENTAL VERIFICATION OF BOUNDED-FORCE CONTROL METHOD     

B. INDRAWAN  T. KOBORI  M. SAKAMOTO  N. KOSHIKA  S. OHRUI 《地震工程与结构动力学》1996,25(2):179-193

An efficient and simple non-linear active control method called Bounded-Force Control (BFC) method has been developed. The theoretical development and application examples of the BFC method has been presented in several publications where it was shown that the BFC is more efficient than the Linear Quadratic Regulator (LQR) method in terms of maximum control force and power requirements when applied to an Active Tuned Mass Damper (ATMD) system. Following a brief review of the fundamental concept of the BFC and a discussion of its main advantages, the results of an experimental investigation using a three-storey shear building model excited by a shaking table and controlled by an electromagnetic linear motor are presented. The experimental results were in perfect agreement with the analytical results, thus confirming the validity of the proposed BFC algorithm.  相似文献   

Magma eruption rates of Merapi volcano,Central Java,Indonesia during one century (1890–1992)     

Suparto Siswowidjoyo  Ismangun Suryo  Izumi Yokoyama 《Bulletin of Volcanology》1995,57(2):111-116

The magma eruption rates of Merapi volcano form 1890 to 1992 are re-examined chronologically. For this volcano, movements of extruded lavas and domes as well as their extrusions are important because they control the modes of the subsequent activities and cause nuées ardentes and lahars. The monthly eruption rates varied widely, but the cumulative volume of lavas has increased linearly and is expressed as 0.1x10⁶ m³/month. The magma production rate of this volcano may have been constant for these 100 years. Recurrent excessive effusion of lavas is tentatively interpreted by assuming a magma reservoir. The averaged eruption rate is small in comparison with other volcanoes such as Nyramuragia, Kilauea and Vesuvio. However, it is remarkable that the activity has been continuous for these 100 years and the total amount of lava discharged during this period reached more than 10⁸ m³. A simple model for the formation of the 1992 lava dome is presented. The viscosity of the lavas is probably between 10⁶ and 10⁷ P and the length of the magma conduit is probably less than 10 km.  相似文献   

A method of artificial generation of earthquake ground motion     

Masahiko Kimura  Masanori Izumi 《地震工程与结构动力学》1989,18(6):867-874

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Seismic energy releases from volcanoes     

Izumi Yokoyama 《Bulletin of Volcanology》1988,50(1):1-13

Seismic energy release during the precursory, eruptive and declining stages of volcanic activities provides various information about the mechanisms of volcanic eruptions and the temporary developments of their activities. Hitherto the energy release patterns from precursory earthquake swarms were used to predict the eruption times, especially of andesitic or dacitic volcanoes. In this paper the discussion is expanded to quantify the total amount of seismic energy released at the threshold of volcanic eruptions, with reference to the results observed at several volcanoes. The results generally indicate that the cumulative seismic energy release from the precursory earthquake swarms exceed 10¹⁷¹⁸ergs before eruptions at any andesitic or dacitic volvanoes. This allows the seismic efficiency, or the ratio of energy radiated seismically, and the energy required for the volumetric expansion to be estimated by incorporating available deformation data with the seismic data. The dependency of seismic efficiency on the type of volcanic activity, i. e. non-explosive outbreaks, phreatic and magmatic eruptions, dome formation, etc., was evaluated from observations at a few volcanoes that provided a variety of examples.  相似文献   

从悬浮质和沉降质的观点描述中国云南湖泊的化学动态变化     

杉山雅人  佐佐木淳也  吉田宽郎  坂本充  宋学良  张子雄 《云南地理环境研究》2002,14(2):20-33

在对云南抚仙湖、星云湖和洱海3个高原湖怕进行地球化学和湖沼学调查，确定湖水中微粒的溶解浓度和化学成分，对沉降质和沉积物进行分析的基础上，对这些湖泊的化学动态变化进行了讨论。  相似文献   

Effect of dietary docosahexaenoic acid on lipogenesis and lipolysis in black sea bream, Acanthopagrus schlegeli   总被引：2，自引：0，他引：2  

JI Hong  OM Ahamd Dau  YOSHIMATSU Takao  UMINO Testuy  NAKAGAWA Heisuke  FURUHASHI Makoto  SAKAMOTO Shuichi 《海洋学报(英文版)》2007,26(1):112-121

1 IntroductionIt is well known that varying dietary fatty acidprofile affects the tissue fatty acid composition and e-ven the growth performance in fish ( Bell et al.,2002; Figueiredo -Silva et al., 2005; Harel andPlace, 2003; Schulz et al., 2005; Tocher et al.,2003). Docosahexaenoic acid (DHA), an importantessential fatty acid for marine species, has the effectnot only on the fatty acid profile of fish body tissue,but also on biological and physiological conditions(Ishizaki et al., 2000; …  相似文献   

CaPtO3 as a novel post-perovskite oxide     

Kenya Ohgushi  Yoshitaka Matsushita  Nobuyoshi Miyajima  Yoshio Katsuya  Masahiko Tanaka  Fujio Izumi  Hirotada Gotou  Yutaka Ueda  Takehiko Yagi 《Physics and Chemistry of Minerals》2008,35(4):189-195

Structural, morphological, magnetic, and thermal properties have been investigated for a novel post-perovskite oxide CaPtO₃ synthesized under high pressure. By comparing obtained structural parameters with those for known post-perovskite compounds, we argue that the chemical bond has a strong covalent character. Precise measurements of the Langevin susceptibility χ ₀ = −9.6 × 10⁻⁵ emu/mol and Debye temperature θ ∼ 470 K provide a good opportunity to confirm the reliability of first-principle calculations on predicting physical properties of the Earth’s D” layer.  相似文献   

Effects of spilled oil on microbial communities in a tidal flat     

Katayama Y  Oura T  Iizuka M  Orita I  Cho KJ  Chung IY  Okada M 《Marine pollution bulletin》2003,47(1-6):85-90

Effects of spilled oil on microbial communities in tidal flats were examined by use of a simulator for a tidal flat ecosystem. The simulator is composed of a wave generator, a tide control device, and a tidal flat. Sediment for the tidal flat was obtained at a natural tidal flat in Hiroshima Bay, Japan. After stabilizing the benthic organisms, fuel oil C was added to the surface of the flat at 1 lm(-2). Although the total number of micro-organisms remained at 1.5-3.5 x 10(9) cells g(-1) dry sediment irrespective of the addition of oil, bacterial communities which were analyzed based on the 16S rDNA showed clear changes after the addition of fuel oil C and after a subsequent recovery period. Bacterial colonies were randomly isolated from the oil-supplemented sediment during the experiments, and the isolates were examined for susceptibility to hydrocarbons in order to screen the oil-susceptible bacteria. The proportion of oil-susceptible bacteria in the isolates decreased with the addition of the oil. Oil-susceptible bacteria showed an inability to assimilate petroleum compounds as well as an inhibition of growth. The possibility of using oil-susceptible bacteria as an indicator of bioremediation in tidal flats was discussed.  相似文献   

Simultaneous hard X-ray and optical observations of Sco X-1 and a model of semi-opaque X-ray sources     

Izumi Kasahara 《Astrophysics and Space Science》1974,29(1):191-210

Simultaneous observations of hard X-ray and optical emission from Sco X-1 were carried out at Hyderabad, India, on April 16 and 19, 1972. During the first and the second observations Sco X-1 was on the average in a bright phase ofB=12.5 mag. and a slightly darker phase ofB=12.7 mag. respectively. During the first observation the X-ray intensity in the energy range 20–40 keV measured with balloon borne scintillation counters showed an enhancement of a factor of about two in coincidence with an optical flare ofB0.2 mag., whereas the apparent temperature derived from the X-ray spectrum observed in the energy range 20–35 keV showed no appreciable change. Both the X-ray intensity and the apparent temperature observed on April 19 are considerably lower than those observed on April 16. Taking into account the effect of radiative transfer in a hot plasma, the electron density and the optical depth for electron scattering of the plasma cloud are derived asn _e 3×10¹⁶ cm^–3 and _es 10 for the quiescent bright phase. The flare is explained by an increase of the plasma mass by about 30% and an increase of _es by _es 1 without appreciable change of the plasma temperature. The results on April 19 is interpreted as indicating that the quiescent dark phase may be characterized by a decrease of the plasma mass, its contraction and lower temperature.  相似文献