Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS th-order Gm-C linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -dB frequency bandwidth, group delay ripple, rd-order distortion, and rd-order input intercept point (IIP) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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The possibility of attenuation of microseismic waves due to the presence of an upward folding of the ocean bottom into the liquid is discussed in this paper. The upward folding of the ocean bottom has been idealized by means of an irregularity in the form of a rectangle intruding into the liquid and the evaluation of the displacement component at any point of the solid medium has been carried out in two stages. First, the change in the incident mode of the surface wave due to the presence of the rectangular irregularity has been determined, and second, the subsequent change of the resulting displacement components due to the termination of the liquid layer and the step change in elevation of the solid medium at the continental margin has been discovered. Finally, numerical calculation has been made to determine the attenuation of the microseismic waves of different periods due to the presence of the rectangular irregularity at the ocean bottom.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MCT-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MCT-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-,-diene-,5α,6β-triol (1). 1 induced ALP activities of MCT-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MCT-1 cells by 1, ergosterol (2), ergocalciferol (), cholesta-,5α,6β-triol (4), -dehydrocholesterol (5) and cholecalciferol (6) were tested. The enzyme activities of MCT-1 cells were increased .0-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2, , 5 and 6 did not induce MCT-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-5 and/or C-6 of 1 and 4 played an important role in their differentiation-inducing activities on MCT-1 cells. Furthermore, 1 suppressed induction of MCT-1 cell apoptosis by serum starvation.

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Failure problems of saturated soils are classified in the present study into the following four types : Type I : The failure of loose and/or normally consolidated soils under fully drained loading conditions. Type II : The same soils but under perfectly undrained conditions. Type III : The failure of dense and/or overconsolidated soils under fully drained conditions. Type IV : The same soils but under perfectly undrained conditions. The soil-water coupling limiting equilibrium analysis on the basis of the critical state concept is shown possible to draw a distinction between type I, II and IV problems, and the limitations of the analysis procedure happen in solving the type problem in the above. This is demonstrated experimentally, in which seepage failure experiments in laboratory with the use of a saturated silty sand are employed to make distinctions clearly between the four types of failure problems. The definite distinctions both in failure load and failure mode appeared in the four types of experiments are summarized as follows : (1) the smallest failure load in loose sand in the undrained condition, (2) the largest failure load with the largest failure region in dense sand under undrained loading, () the observation of no global deformation before failure within the soil under the fully drained condition that suggests the development of very localized shear deformation in the sand. Three out of four experiments are described well by the limit analysis computation mentioned above as far as the failure load and the shape and the size of the failure region after boiling failure are concerned, and thus the type III problem is identified to be the problem that should be solved by any other means in near future.

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A 5kW class Stirling engine generator has been developed with the aim of constructing a system mainly for service use. The Stirling engine is built up as a 2-piston type with driving mechanism. It has a hot cylinder and a heat-exchanger cylinder in which a regenerator and a cooler are installed, and the both cylinders are connected by a heater made by U-shape tubes. The developed Stirling engine generator is unified hermetically because of including a PM synchronous generator in the driving mechanism. From the results of performance test, electric power is .92kW and efficiency is 31.4% based on thermal heat into the engine. It is effective in environmental preservation and energy saving to apply the developed Stirling engine generator to a power generation and heat supply system with heat source of wastes and wood biomass, since a heater shape is suitable for absorbing heat form combustion gas.

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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; (1) the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, () the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, (4) the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, (5) The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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The correction factor (η_ie) for the ultimate bearing capacity of a footing placed adjacent to a slope, taking into account the combined effect of horizontal and vertical seismic loads, represented by horizontal and vertical seismic coefficients, k_h and k_v, respectively, was derived using a modified Janbu's slice method. The influence of slope angles ‘α’ on the values of ‘η_ie’ are studied here. It was found that the values of η_ie can be expressed as an exponential function of ‘k_h/(1-k_v)’ and ‘α’, with a measurable interdependency between ‘α’ and ‘η_ie’. The influence of ‘α’ on the value of ‘η_ie’ increases as the input value of ‘k_h/(1-k_v)’ increases. Equations derived based on the analytical results are proposed to account for this effect. Based on the analyses of 11 near-fault seismographers obtained in the 1999 Chi-Chi earthquake in Taiwan, a ratio between the vertical and the horizontal seismic coefficients, λ, of between ±0.25 is suggested for including the combined effect of vertical and horizontal seismic forces in evaluating the seismic bearing capacity of footings located in near-fault areas.

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At present, analytical or empirical formula for seismic bearing capacity of footings adjacent to slopes is not available. This study uses a pseudo-static-based approach in conjunction with rigorous Janbu's slice method to derive analytical values of seismic bearing capacity factors (N_γ) and correction factors for the effects of inertia of soil mass and load inclinations for a rigid footing adjacent to cohesionless slopes. It is shown that both the bearing capacity factors (N_γ) and the correction factors for the seismic bearing capacity of footings placed on level ground derived herein are comparable with those reported in the literature. Empirical equations regarding the effects of slope angles and load inclinations, expressed using generalized forms of those proposed in the literature, are also derived. It is also found that the empirical equations derived in the present study provide values of correction factors in good agreements with the analytical ones, indicating the validity of using these empirical equations for assessing the bearing capacity of rigid footings situated on the slope subjected to pseudo-static seismic loading.

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Electrophoretic displays (EPDs) have been used in

-Readers for over a decade. These products have been widely adopted by consumers because of the superior user experience enabled by EPDs. Today, hospitals have also been evaluating products with this technology because of the improved experience it provides to both patients and hospital staff.

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  The distribution of sarcophytol-A in the Sarcophyton genus was investigated in seven samples belonging to S. glaucum ( samples), S. infundibulifurme (2 samples), S. crassocaule (1 sample) and S. trocheliophorum (1 sample) that were collected on Ishigaki Island in Okinawa Prefecture. Sarcophytol-A was present in one sample each of S. glaucum and S. infundibulifurme. This study indicates that the composition of cembranoids in the Sarcophyton genus is not related with the respective species, but with the individual samples collected.

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The 1973's end world oil crisis and sudden price increase of petroleum products in year 1979 have led all the ship owners to look more closer into the transportation fuel cost reduction by evaluating precisely the influence of their ship's operation condition and selecting the fuel saving engines.
As it establishes that now the thermo-dynamic efficiency of the marine propulsion engines, low speed engines or medium speed engines, increases to 45% what represents a specific consumption lower than 140 gr/ps-h, the writer explains on the base of our experience that the further fuel saving of the medium speed engine which may be realized by reconsidering the fuel consumption reduction of engine itself & propulsion plant and heat recovery of exhaust gas etc., will reach more 15% comparing the fuel expenses in the conventional installation with long stroke low speed engines.
Furthermore, how to burn the future fuel and coal on the medium speed engines are described.

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