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  • 末次 康将
    マリンエンジニアリング
    2021年 56 巻 5 号 680-687
    発行日: 2021/09/01
    公開日: 2021/10/12
    ジャーナル フリー
  • / 鵜飼 恵三, KEIZO UGAI
    地盤工学会論文報告集
    1998年 38 巻 3 号 201-207
    発行日: 1998/09/15
    公開日: 2008/02/29
    ジャーナル フリー
    A comparative study of the static and dynamic response of a slope is carried out, using the large deformation theory of the updated Lagrangian formulation and the conventional infinitesimal theory. In the static analysis, a strength reduction method proposed by one of the authors is used to evaluate the safety factor of the slope. It is found that by the large deformation theory, the safety factor is larger than that calculated by the infinitesimal theory, and this difference becomes large along with the reduction of elastic modulus. In the dynamic analysis, it is observed that the large deformation theory gives smaller sliding displacement and larger response acceleration than the infinitesimal approach. It is concluded that in many cases the large deformation approach gives more adequate solutions.
  • 張 建民, 社本 康広, 時松 孝次
    地盤工学会論文報告集
    1998年 38 巻 2 号 143-163
    発行日: 1998/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    Based on the concept "intermediate soil wedge" which is dependent on mobilized frictional resistance, a new theory has been developed for evaluating the seismic earth pressures against retaining walls under any condition between the active and passive states. For this theory, the seismic earth pressure is separated into four components according to their formation. New equations are proposed to determine the distribution, resultant and point of application for each component. An equivalent seismic coefficient is introduced to take into account non-uniform seismic acceleration distribution with depth. The equations place special emphasis on dependence of the seismic earth pressure on mode and level of wall movement. The equations can be reduced to the Mononobe-Okabe equation for the limiting conditions. Their applicability was confirmed by comparing the predictions with a number of previous model test results.
  • RAJ SIDDHARTHAN, GARY M. NORRlS
    土質工学会論文報告集
    1991年 31 巻 2 号 51-64
    発行日: 1991/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    A finite element model capable of taking into account nonlinear hysteretic soil behavior is presented to study earthquake induced retaining wall movement. The model also accounts for increase in lateral stresses and settlement associated with grain slip caused by cyclic loads. The predictive capability of the proposed method is verified by comparing responses given by the model with those computed by another existing finite element model and also with responses recorded at the Cambridge centrifuge facility. The study reveals that the wall displacement can be substantially affected, among other factors, by the increase in lateral stresses due to grain slip and wall-soil friction. Care should be taken when selecting a constant value of wall-soil friction angle for the entire duration of excitation since structural changes can occur in the soil adjacent to the wall.
  • CHANIDNUN POTHIRAKSANON, DENNES T. BERGADO, HOSSAM M. ABUEL-NAGA
    SOILS AND FOUNDATIONS
    2010年 50 巻 5 号 599-608
    発行日: 2010年
    公開日: 2010/12/28
    ジャーナル フリー
    In this study the field feasibility of an innovative thermal technique to improve the performance of prefabricated vertical drains (PVD) used in conjunction with the preloading ground improvement method is investigated. For this purpose, two identical 6.0 m high full-scale test embankments for preloading were constructed over the soft Bangkok clay where a conventional PVD system was installed underneath one embankment and a novel prefabricated vertical thermo-drain (PVTD) system was utilized for the other. The PVTD unit consists of a U-tube made of cross-linked polyethylene plastic (PEX) that is attached to a conventional PVD unit. Preheated water at about 90°C is circulated through the attached U-tube to raise the soil temperature underneath the PVTD embankment. The behavior of the two test embankments were compared in terms of excess pore water pressure and consolidation results. The comparison shows the advantage of a PVTD system over a conventional PVD system. The rate of consolidation increases significantly in the PVTD system due to the temperature effect on the hydraulic conductivity. Moreover, the embankment with the PVTD system generates more settlement due to the thermally induced irreversible contraction of saturated normally consolidated soft Bangkok clay.
  • 伊藤 孝男, 森 芳信, 浅田 秋江
    土質工学会論文報告集
    1994年 34 巻 1 号 33-40
    発行日: 1994/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    During earthquakes, saturated loose sandy soils often liquefy, causing serious damage to buildings and underground structures. Various construction methods have been employed to stabilize these soils against liquefaction. The popular methods are those which increase their density. Vibration and impact methods are commonly employed, but these often pose a problem of noise and vibration in urban areas. Results of previous experiments have shown that Quick Lime Consolidated Briquettes (QCB), a soil stabilizer made of quicklime and cement placed to form cylinders, significantly increases resistance to liquefaction by utilizing the effects of water absorption, swelling, and hardening. In the present study, shaking table tests were performed to evaluate the earthquake resistance of soil treated with QCB. Results of these test showed that the response acceleration and excess pore water pressure in QCB-treated soils were scarcely affected by the excitation of 200 Gals. The soil settlement due to shaking was about one tenth of that for the untreated soil, proving the effectiveness of QCB during earthquakes.
  • 國生 剛治
    地盤工学会論文報告集
    2000年 40 巻 5 号 99-111
    発行日: 2000/10/15
    公開日: 2008/02/29
    ジャーナル フリー
    In view of the significant role of the water film effect in flow failure for a liquefied sandy deposit, the mechanism of water film generation is numerically studied based on a 1-dimensional model test. The process of water film growth and decay can be simulated to a certain extent by a simple consolidation analysis, which indicates that only a small difference in permeability in layered sand is enough for a water film to develop. A 1 G shaking table test for a two-dimensional slope model with an arc of silt within a saturated sand is then addressed to discuss the dilatancy effect exerted in sheared sand during flow failure. It is possible that, once the water film is formed, the transmission of shear stress through it is interrupted, leaving the sand below free from the dilatancy ; this eventually allows the water film to stay without being absorbed during flow failure. The result of another shaking table test for a trapezoidal slope with horizontal silt seams indicate that water films beneath the seams enable the soil mass above them to laterally flow along water films very gently inclined even after shaking. If a silt seam breaks due to excessive pressure in the water film, it triggers re-liquefaction in the upper sand and leads to further instability.
  • T BAKER, C. RANGACHARYULU
    日本物理学会講演概要集
    1999年 54.2.1 巻 23pSM-6
    発行日: 1999/09/13
    公開日: 2018/03/04
    会議録・要旨集 フリー
  • 藤原 東雄, 上 俊二
    土質工学会論文報告集
    1990年 30 巻 1 号 76-86
    発行日: 1990/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.
  • 東坂 諒哉, 城 克己, 林 侑加子, 津村 ゆかり
    日本法科学技術学会誌
    2023年 28 巻 2 号 197-203
    発行日: 2023年
    公開日: 2023/07/31
    [早期公開] 公開日: 2023/04/20
    ジャーナル フリー

     The stability of

    Δ9
    ‒tetrahydrocannabinol acetate (
    Δ9
    ‒THC‒OAc) and
    Δ8
    ‒tetrahydrocannabinol acetate (
    Δ8
    ‒THC‒OAc) in
    e
    -liquid during storage was investigated.
    Δ9
    ‒THC‒OAc liquids in cartridges were stored at
    80
    ℃ or 30℃ for 28 days. The relative concentrations of cannabinoids in the liquids were measured by gas chromatography with flame ionization detection.
    Δ9
    ‒THC‒OAc decreased during storage at either temperature.
    Δ9
    ‒THC, a minor impurity, also decreased.
    Δ8
    ‒THC‒OAc liquid in a cartridge was stored at
    80
    ℃ for 57 days. The concentration of
    Δ8
    ‒THC‒OAc and
    Δ8
    ‒THC, a minor impurity, did not change during that time. Cannabinol acetate increased in all liquids, and unknown products were also detected by gas chromatography/mass spectrometry (GC/MS). The
    Δ9
    ‒THC‒OAc and
    Δ8
    ‒THC‒OAc liquids were subjected to GC/MS to detect representative diluents, glycerol, propylene glycol, and polyethylene glycol 400, but none of these were detected.

  • LIVIO SIROVICH
    地盤工学会論文報告集
    1996年 36 巻 4 号 23-34
    発行日: 1996/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA
    2
    programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.
  • ASHRAF GHALY, ADEL HANNA, MIKHAIL HANNA
    土質工学会論文報告集
    1991年 31 巻 2 号 77-92
    発行日: 1991/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    The performance of single pitch and multi pitch screw anchors during the application of installation torque is presented. An experimental testing program was conducted using five models of screw anchors with different geometry. The effect of the shape of the screw element, sand properties, and installation depth on the required installation torque value was examined. A theoretical model was developed from which the required installation torque value can be calculated in terms of the influencing factors. The required installation torque can be determined in terms of the ultimate uplift resistance calculated from any of the available theories. Based on the actual installation torque value measured in the field, the anticipated pullout capacity can be back calculated from the present theory. A comparison between theoretical and experimental results showed good agreement. Also, good agreement was observed when the present theoretical results were compared with the available field results reported in the literature.
  • 辻川 健治, 川上 貴大, 荒木 渉, 佐藤 高広, 伊藤 さよ, 和泉 要, 保戸田 滉樹, 岩田 祐子
    日本法科学技術学会誌
    2023年 28 巻 2 号 145-157
    発行日: 2023年
    公開日: 2023/07/31
    [早期公開] 公開日: 2023/04/20
    ジャーナル フリー

     We examined the stability of

    Δ9
    -tetrahydrocannabinol acetate (
    Δ9
    -THC-OAc) and
    Δ8
    -tetrahydrocannabinol acetate (
    Δ8
    -THC-OAc) in
    e
    -liquid products. Eight samples were heated at 30℃ for 28 days and one of them was heated at 70℃ for
    2
    ,
    4
    ,
    8
    , 10, and 15 days. Residual ratios of
    Δ9
    -THC-OAc and
    Δ8
    -THC-OAc were evaluated by gas chromatography with flame ion detection and their degradation products were examined by gas chromatography/mass spectrometry (GC/MS). Some samples were tested for solubility in hexane and were submitted to GC/MS analysis to detect propylene glycol and glycerol. After a 28-day incubation at 30℃,
    Δ9
    -THC-OAc was slightly decomposed (residual ratio: 84.
    5
    –94.
    2
    %) but
    Δ8
    -THC-OAc was almost stable (residual ratio: 95.
    2
    –108.
    9
    %). Heating at 70℃ decomposed not only
    Δ9
    -THC-OAc but also
    Δ8
    -THC-OAc. The decomposition proceeded rapidly in the initial
    2
    days then slowly until 15 days later. The degradation products, four putative one-oxygen-atom adducts and cannabinol, were detected but deacetylated products (
    Δ9
    -tetrahydrocannabinol and
    Δ8
    -tetrahydrocannabinol) were not detected. All the samples tested were completely dissolved in hexane differently from propylene glycol and glycerol. Propylene glycol and glycerol were not detected from the samples completely dissolved in hexane. This study indicated that deacetylation of
    Δ9
    -THC-OAc and
    Δ8
    -THC-OAc did not proceed when the sample did not contain propylene glycol and glycerol.

  • 西村 真一, 清水 英良, / 仲野 良紀, RYOKI NAKANO
    地盤工学会論文報告集
    1998年 38 巻 3 号 89-95
    発行日: 1998/09/15
    公開日: 2008/02/29
    ジャーナル フリー
    Leakage of water due to internal erosion through a dam body or foundation is a major problem with fill-type dams. Recent case histories and research suggest that most cases of internal erosion are possibly triggered by hydraulic fracturing. However, the quantitative mechanism of hydraulic fracturing still remains to be solved. Therefore in-situ hydraulic fracture tests were carried out with a cheap, concise apparatus using boreholes dug in the soft clayey volcanic soil foundation of a low earth dam (Oyachi Dam) in Niigata Prefecture. Water was injected into the foundation through a perforated pipe by two methods : one was under a controlled injection pressure and the other was a controlled injection flow rate. In the former method, the relationship between flow rate and injection pressure was observed and it was found that a yield pressure or fracture pressure existed in all the tests. By repeating the injection test it was confirmed that once a crack is developed, it is very easily reopened by a water pressure a little higher than the earth pressure exerted on the crack. In the latter method, the relationship between injection pressure and time was observed and it was found that fracture pressure varied with flow rate. The boreholes were excavated to observe the development of fracture cracks and it was also found that the cracks had developed perpendicular to the borehole periphery, which means that fracture cracks were induced by tensile stress and denies the explanation that fractures are caused by shear failure.
  • Suguru TAKATSUTO, Kiyomi KOBAYASHI, Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE
    Agricultural and Biological Chemistry
    1988年 52 巻 12 号 3217-3218
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • 鍛治 健司, 葛谷 昌之 /, RAYMONDN. CASTLE
    Chemical and Pharmaceutical Bulletin
    1970年 18 巻 1 号 147-156
    発行日: 1970/01/25
    公開日: 2008/03/31
    ジャーナル フリー
    2
    -Benzyl-
    4
    -chloro-
    5
    -mercapto-
    3
    (
    2
    H)-pyridazinone (1) was heated in ethanol under reflux for 10 hours to form concurrently
    2
    , 7-dibenzyldipyridazo [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-1,
    4
    -dithiin-1, 6 (
    2
    H, 7H)-dione (Ia) (57% in yield) and
    2
    ,
    8
    -dibenzyldipyridazo [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-1,
    4
    -dithiin-1,
    9
    (
    2
    H,
    8
    H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-1,
    4
    -dithiin-1, 6 (
    2
    H, 7H)-dione and the -1,
    9
    (
    2
    H,
    8
    H)-dione were observed in, not only heating
    4
    -chloro-
    5
    -mercapto-
    3
    (
    2
    H)-pyridazinones (1-
    3
    ) in polar solvent, but warming
    4
    -mercapto-
    5
    -chloro-
    3
    (
    2
    H)-pyridazinones (
    4
    -6) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as
    2
    -phenylimino-
    5
    -benzylpyridazo [
    4
    ,
    5
    -
    d
    ]-1,
    3
    -dithiol-
    4
    (
    5
    H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming 1 with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at
    80
    °, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.
  • CHAIM J. PORAN, KINGSEN HEH, JORGE A. RODRIGUEZ
    土質工学会論文報告集
    1992年 32 巻 4 号 81-92
    発行日: 1992/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    The paper presents results from an extensive experimental model study of response of dry sand to impact of a rigid tamper. In the laboratory tests a circular steel tamper was repeatedly dropped on sand contained in a large tank. Measurements included tamper acceleration aud soil pressure at impact, tamper settlement, aud soil densities and strains. Effects of tamper drop height, weight and contact area were investigated. A method is presented for the evaluation of global dynamic stiffness of the soil mass affected by the impact by calculating a dynamic settlement modulus (DSM). The DSM values are determined from integration of the impact acceleration record with respect to time using measured integration constants. DSM values show good correlation to soil densities and corresponding elastic moduli obtained from laboratory tests for loose sand. However, for dense sand, results indicate apparent discrepancies between elastic modulus and the higher DSM values. Analyses of normalized impact energy and the resulting densification in the sand in terms of normalized dimensions of volumetric strain (relative density) contours show unique correlations which are used for a proposed rational design method for dynamic compaction in dry sandy soils.
  • 小田切 孝人, 田代 眞人
    ウイルス
    2013年 63 巻 2 号 233-240
    発行日: 2013/12/25
    公開日: 2014/10/31
    ジャーナル フリー
  • Cbesseredes HORTS
    Journal of Human Ergology
    1982年 11 巻 Supplement 号 429-440
    発行日: 1982/12/15
    公開日: 2011/02/23
    ジャーナル フリー
  • Hugang HAN
    バイオメディカル・ファジィ・システム学会大会講演論文集
    2010年 23 巻 9P-E-8
    発行日: 2010/10/09
    公開日: 2017/10/25
    会議録・要旨集 フリー
    In this paper, instead of the time-invariant state-space representation in the consequent of the T-S fuzzy model, tim,
    e
    -varying system is considered in order to deal with the reconstruction error between the real system to be controlled and its T-S model, and fuzzy approximator is employed to cope with unknown functions involved in the model. As a result, it reaches an adaptive controller that has two parts: one is obtained by solving certain linear matrix inequalities (LMIs) (fixed part) and another one is acquired by the fuzzy approximator in which the related parameters are tuned by adaptive law (variable part). The proposed controller can guarantee the closed-loop system to be asymptotically stable.
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