It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s=1 and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; () Safety factors are defined also on interblock planes; and () All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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A method for analyzing the uncertainties involving the use of empirical relationships in design is developed. It is applied to evaluate the reliability of the relationship s_u(mobilized)=(measured), whereby the pertinent uncertainties are analyzed using extensive laboratory and field observed data. On the average, the relationship s_u(mobilized)= (measured) is unbiased and the error implicit in the relationship is about 15%. When cone values are used to infer s'_p, additional uncertainties on the mobilized undrained strength will incur resulting mainly from the calibration uncertainty between σ'_p and the cone values. Alternatively, vane tests may be performed to infer the mobilized strength using Bjerrum correction factor. Results show that uncertainty level associated with using the vane tests is smaller than that using the cone values, provided that similar scatter is observed between measured vane and cone values at a given site. However, prediction of the mobilized strength is even more accurate if direct measurements can be made on the preconsolidation pressure. The proposed probabilistic method also assesses the benefit of additional tests besides comparing the accuracy of using various soil parameters for predicting mobilized undrained strength. Such information is essential for planning cost-effective site characterization program.

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(,)-,-エポキシ-,7,11,11-テトラメチルシクロウンデカ-,-ジエン()をフムレン1((,,)-,7,11,11-テトラメチルシクロウンデカ-,,-トリエン)より合成する既知の合成法は実際に牧率が低く合成的に問題がある.さらに,の合成はその反応性や物性の研究のために簡単に高牧率で行われることが望まれる.今回,の新たな合成法と簡便な精製法を見いだし,を高牧率で1から合成することができたので報告する.1のジエポキシ化,続く再結晶により得られたジエポキシド()は二価のチタンにより還元されて,1(273%)と(25%)と少量のを含むを主生成物(42.7%)として与えた.1とは原料として再利用できる.の精製は1と同様硝酸銀()錯体の結晶で行い,純粋なは1から通算牧率32.0%で得られた.の既知方法による合成は4段階の反応と数回のカラム分離及び10%含浸シリカゲルカラム分離を必要とし牧率が極端に低い.今回,新しいの合成法は段階の反応で1回のカラム分離と再結晶により高い通算牧率を示す.

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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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The pseudo-static analysis has been used in engineering practice to simplify the computation of the upper limit of a slope under seismic load. In this paper, the upper bound technique of limit analysis of perfect plasticity is used to determine the bearing capacity of a foundation near a down-hill slope. In this analysis (Chen et al., 1969; Chen, 1975), a logarithmic spiral rapture (Abdul-Baki et al., 1970; Sawada et al., 1984) is assumed to start at an edge of the loaded area far from the slope. A landslide is assumed to be of rigid body type with the inertia force acted at its center of gravity. The collapse state is reached when the rate of kinematic energy of the landslide together with the load is equal to the rate of dissipation of internal energy along the sliding surface. This energy balance leads to the equation of ultimate load with several parameters. The optimized numerical rcsults with respect to these parameters are compared with those by Kotter's method (Yamaguchi, 1959) and those obtained by the slice method.

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Two new polyacetylene compounds (4, , 12)-1-acetoxy--isovaleryloxytetradeca-4, , 12-trien-, 10-diyn-14-ol (), and (4, , 12)-1-acetoxy--(-methylbutyryloxy)tetradeca-4, , 12-trien-, 10-diyn-14-ol (C) have been isolated along with (4, , 12)-1-acetoxy--senecioyloxytetradeca-4, , 12-trien-, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

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This paper presents reinforcing mechanisms and a method for analyzing reinforced earth structures. The reinforcing mechanism presented is divided into two stages, a fixed slip surface and an arbitrarily selected slip surface. The mechanism is studied through direct shear tests and plane strain compression tests including some geotextiles. The reinforcing materials considered in this paper only have tensile strength. The authors have already proposed a method called Generalized Limit Equilibrium Method (GLEM) for analyzing stability problems. The validity of the method has already been shown in previously published papers. In this paper, the method is extended to carry out a stability analysis for reinforced earth structures. Finally, large scale model tests for the bearing capacity of foundations on reinforced slopes were carried out to investigate the validity of the proposed reinforcing mechanism and the analytical method. Through comparisons of observations of experiments and results of the analytical method, the validity of the present work is demonstrated.

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Nアルキル,4:,10-ペリレンテトラカルボン酸モノアンヒドリド=モノイミド[4a～]と芳香族アミン(アニリン,p-トルイジン,p-アニシジン,,-キシリジン,4-アミノナゾベンゼン,およびo-フェニレンジアミン)を縮合して非対称型,4:,10-ペリレンビス(ジカルボキシミド)誘導体-N-アルキル-N'-アリール-,4:,10-ペリレンビス(ジカルボキシミド)(〔a～〕,〔a～〕,〔7a～〕,〔a～〕,〔a～〕,および〔10a～〕)を合成した. これらの各誘導体はすべて赤色系の色相を示し, 顔料試験の結果N-ブチル-N'-アリール-,4:,10-ペリレンビス(ジカルボキシミド)(たとえば〔〕や〔〕)がとくにすぐれた耐光性を示した.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in -D applications; i.., unlike other methods, its extension to -D is straightforward.

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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 7th-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 7th-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, .%, ≤ -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.V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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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-7,-diene-,,-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 (), ergocalciferol (), cholesta-,,-triol (4), 7-dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MCT-1 cells were increased .0-fold by 10 μM 1 and .4-fold by 10 μM 4. However, , , and did not induce MCT-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C- and/or C- 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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