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排序方式: 共有1485条查询结果,搜索用时 15 毫秒
981.
982.
Md Rasel Sheikh Yukio Nakata Munehiko Shitano Masahiro Kaneko 《Soils and Foundations》2021,61(4):1033-1053
Real-time unstable slope monitoring is essential for recognition of landslide occurrence, as well as for early warning to reduce landslide-induced damages. This study investigated an unstable slope monitoring system that consists of tilt sensors aiming to establish an advanced time prediction model (TPM) for landslide early warning. The monitoring process utilized additional support devices (e.g. pipe strain gauges, water level gauges and a rain gauge) installed on a natural cut slope site. The tilt sensors could detect movements (in tilt angle) within the slope generated by heavy rains. Analysis of the recorded data revealed that the rate of movement, or tilt, was influenced by groundwater table fluctuations and antecedent rainfalls. A relationship between the tilt rate and the horizontal displacement calculated from pipe strain value has been established. Subsequently, a new classification of slope movement was proposed according to the tilt rates obtained from the deformation process of the slope. Considering the movement characteristics, two warning levels were identified such as warning and evacuation. Further, an advanced TPM was proposed in relation to realtime slope surface tilt rates. The TPM could provide efficient results at the continuous acceleration phase of the landslide occurrence. Therefore, we suggest this technique can be applied for monitoring and early warning of rainfall-induced shallow landslides. 相似文献
983.
Based on a magnetization integral equation, a magnetic field analysis method was developed for 3-D complicated components formed by thin shells. The agreement between numerical results and experimental ones was good, confirming the validity of this method. The method was applied to the analysis of magnetic induction and stress in a ferromagnetic first wall for a tokamak power reactor. It was found that the wall could be used in a fusion reactor without much problem 相似文献
984.
N Tanida Y Fukui H Tsuzuki T Sugimoto H Miki T Mutsuda S Kita K Kobayashi C Hirose K Seki 《Canadian Metallurgical Quarterly》1995,48(3):239-241
A 64-year-old female was referred to our hospital for further examination of a coin lesion, 8 mm in diameter, superimposed on the right ninth posterior rib. CT revealed a nodule, close to the minor fissure, with spiculation, which seemed to be connected with the pulmonary vein. Since the bronchofiberscopic examination revealed no histological diagnosis, the exploratory thoracotomy was performed. The nodule was found to be a 10 x 7 x 5 mm black mass located subpleural at the minor fissure. Histologically, it was recognized as a lymph node with anthracosis and silicotic nodules. 相似文献
985.
Radiographs of hand and hip joints of 15 hemodialysis patients taken annually over at least 15 years were evaluated in this retrospective study. We looked for signs of A beta 2M-amyloidosis such as lucencies, erosions, and soft tissue swelling. The femoral head-soft tissue distance (FHSTD) was used to estimate the soft tissue swelling of the hips. The number and size of lucencies, the number of erosions, and the FHSTD increased during dialysis. Both hyperparathyroidism and failure of renal allograft transplantation influenced the development of lucencies and erosions after 15 years. The FHSTD at the start of the dialysis appeared to be an independent prognostic factor for the lucencies of the hips and hands. We conclude that the radiological signs of A beta 2M-amyloidosis are influenced not only by the duration of dialysis, but also by age, failure of renal transplantation, hyperparathyroidism and the FHSTD at the start of dialysis. 相似文献
986.
Assessment of tumor extent in extrahepatic bile duct cancers--utility of intraductal ultrasonography
K Tamada N Ueno M Ichiyama H Seki T Kanou M Fukuda T Tomiyama T Nishizono T Iwao K Kimura 《Canadian Metallurgical Quarterly》1994,91(4):863-874
Intraductal ultrasonography (IDUS) were performed in patients with extrahepatic bile duct cancer and compared to other diagnostic modalities and to resected specimens. Endoscopic ultrasonography (EUS) is a non-invasive diagnostic method useful for screening patients with bile duct cancers and determining whether they are resectable or not. While, EUS was not useful for the differential diagnosis of advanced and early tumors, and less useful in case of bile duct tumors located at the hilus hepatitis. IDUS proved useful without blind spot even in case of bile duct cancers at the hilus hepatis. IDUS was especially useful for the differential diagnosis of advanced and early tumors. IDUS is the very accurate diagnostic modality which make up for EUS and essential to determine the appropriate operation plan. 相似文献
987.
To further define the origin, selection, and diversity of hepatic T cells, we have determined V beta gene expression profiles in double negative (DN, CD4-8-) and single positive (SP, CD4+8- or CD8+4-) alpha beta + liver T cells of DBA/2 mice. These I-E+ mice express mouse mammary tumor (Mtv) provirus-encoded endogenous superantigens of the Mlsa,c type, and thus display deletions/depletions of several V beta-bearing SP cells. Total liver alpha beta + T cells of these mice exhibited an overall V beta expression profile similar to splenic T cells, with the notable exception of high V beta 7 and V beta 8.1 expression. As previously reported, DN alpha beta + T cells were enriched highly in the liver. This subset exhibited a V beta expression profile similar to thymic DN alpha beta + cells with deletions/depletions in several V beta s, but high V beta 7 expression in both populations. Surprisingly, hepatic CD4+ cells also displayed high V beta 7 expression compared with splenic T cells, suggesting that hepatic DN alpha beta + and CD4+ T cells are selected via a common pathway. The V beta 7-expressing DN alpha beta + and CD4+ liver T cell populations were polyclonal, as evidenced by cloning and sequencing. High V beta 7 expression in these cells was undiminished with age. On the basis of V beta repertoire and surface phenotype, DN alpha beta + and/or certain CD4+ T cells seem to constitute a distinct population primarily found in the liver, thymus, and bone marrow. These cells may originate from SP T cells that have down-regulated their accessory molecules under certain activation conditions and, because of the accompanying expression of particular adhesion molecules, they accumulate in tissues such as the liver and thymus. 相似文献
988.
Kenji Yonezawa Katsuyoshi Imoto Yukio Watanabe Masahito Akimoto 《Nuclear Engineering and Design》2002,212(1-3)
As presented in the papers of the SMiRT-14, (Dameron and Hessheimer), ultimate capacity pressure tests on a 1/4 scale prestressed concrete containment vessel (PCCV) model were performed in year 2000. First of all, the authors conducted an approximate preliminary analytical investigation to predict its non-linear behavior up to ultimate capacity and to roughly estimate its potential failure mode. The target of this paper is not only to predict the non-linear behavior of the 1/4 PCCV model, but also to establish a reliable method for evaluating actual PCCVs subjected to internal pressure. This paper describes modeling methods and results of two global analyses: (1) modification of friction effects between concrete and unbonded tendons, which play an important role in determining force distributions and relative slip amount of tendons, especially curved ones; (2) results of two global analyses of a 3D-shell 360° model and an axisymmetric model. Feasibility of the analysis method proposed for the actual PCCVs is discussed here. 相似文献
989.
Jun Aihara Shohei Ueta Masaki Honda Naoki Mizuta Minoru Goto Yukio Tachibana 《Journal of Nuclear Science and Technology》2021,58(1):107-116
ABSTRACT The concept of Pu-burner high temperature gas-cooled reactor (HTGR) has been proposed to more safely reduce the amount of recovered Pu. In the Pu-burner HTGR concept, coated fuel particles with ZrC-coated yttria-stabilized zirconia containing PuO2 (PuO2-YSZ) kernels are employed for very high burn-up and high nuclear proliferation resistance. The role of ZrC layer is that of oxygen getter. CeO2-YSZ kernels were fabricated to simulate the PuO2-YSZ kernel and coated with a ZrC layer. In this study, we clarified that both Ce-rich grains and Zr-rich grains were densely distributed in surface regions of the as-fabricated CeO2-YSZ kernel. However, we have already clarified that the surface region of the CeO2-YSZ kernel coated with a ZrC layer was porous and mainly consisted of Zr-rich grains. These experimental results confirmed that Ce-rich grains were selectively corroded during the ZrC coating process. Then, the chemical stability of Zr-rich grains would be higher than that of Pu-rich grains. Thus, it would be more difficult to extract Pu from PuO2-YSZ kernels (in which almost all grains are Zr-rich) than from PuO2-YSZ kernels (in which many Pu-rich grains are included). Influences of the sintering of fuel compact on the microstructure of the ZrC-coated CeO2-YSZ kernel is also reported. 相似文献
990.
用于填充白炭黑轮胎的化学改性E-SBR 总被引:1,自引:0,他引:1
由于汽车制造商面对环保压力,降低滚动阻力已变得重要。化学改性E-SBR在白炭黑填充的胶料中表现出良好的滞后损失性能。 相似文献