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51.
Thermal buckling of cross-ply laminated composite and sandwich plates according to a global higher-order deformation theory 总被引:4,自引:0,他引:4
A two-dimensional global higher-order deformation theory is presented for thermal buckling of cross-ply laminated composite and sandwich plates. By using the method of power series expansion of continuous displacement components, a set of fundamental governing equations which can take into account the effects of both transverse shear and normal stresses is derived through the principle of virtual work. Several sets of truncated Mth-order approximate theories are applied to solve the eigenvalue problems of a simply supported multilayered plate. Modal transverse shear and normal stresses can be calculated by integrating the three-dimensional equations of equilibrium in the thickness direction, and satisfying the continuity conditions at the interface between layers and stress boundary conditions at the external surfaces. Numerical results are compared with those of the published three-dimensional layerwise theory in which both in-plane and normal displacements are assumed to be C0 continuous in the continuity conditions at the interface between layers. Effects of the difference of displacement continuity conditions between the three-dimensional layerwise theory and the global higher-order theory are clarified in thermal buckling problems of multilayered composite plates. 相似文献
52.
Shape from Shading with Interreflections Under a Proximal Light Source: Distortion-Free Copying of an Unfolded Book 总被引:2,自引:0,他引:2
Wada Toshikazu Ukida Hiroyuki Matsuyama Takashi 《International Journal of Computer Vision》1997,24(2):125-135
We address the problem of recovering the 3D shape of an unfolded book surface from the shading information in a scanner image. This shape-from-shading problem in a real world environment is made difficult by a proximal, moving light source, interreflections, specular reflections, and a nonuniform albedo distribution. Taking all these factors into account, we formulate the problem as an iterative, non-linear optimization problem. Piecewise polynomial models of the 3D shape and albedo distribution are introduced to efficiently and stably compute the shape in practice. Finally, we propose a method to restore the distorted scanner image based on the reconstructed 3D shape. The image restoration experiments for real book surfaces demonstrate that much of the geometric and photometric distortions are removed by our method. 相似文献
53.
2D Materials: Re Doping in 2D Transition Metal Dichalcogenides as a New Route to Tailor Structural Phases and Induced Magnetism (Adv. Mater. 43/2017) 下载免费PDF全文
54.
Sota H Yoshimine H Whittier RF Gotoh M Shinohara Y Hasegawa Y Okahata Y 《Analytical chemistry》2002,74(15):3592-3598
Despite high theoretical sensitivity, low-cost manufacture, and compactness potentially amenable to lab-on-a-chip use, practical hurdles have stymied the application of the quartz crystal microbalance (QCM) for aqueous applications such as detection of biomolecular interactions. The chief difficulty lies in achieving a sufficiently stable resonance signal in the presence of even minute fluctuations in hydrostatic pressure. In this work, we present a novel versatile planar sensor chip design (QCM chip) for a microliter-scale on-line biosensor. By sealing the quartz resonator along its edges to a flat, solid support, we provide uniform support for the crystal face not exposed to solvent, greatly decreasing deformation of the crystal resonator under hydrostatic pressure. Furthermore, this cassette design obviates the need for direct handling when exchanging the delicate quartz crystal in the flow cell. A prototype 27-MHz sensor signal exhibited very low noise over a range of flow rates up to 100 microL/min. In contrast, signals obtained from a conventional QCM sensor employing an O-ring-based holder were less stable and deteriorated even further with increasing flow rate. Additional control designs with intermediate amounts of unsupported undersurface yielded intermediate levels of stability, consistent with the interpretation that deformation of the crystal resonator under fluctuating hydraulic pressure is the chief source of noise. As a practical demonstration of the design's high effective sensitivity, we readily detected interaction between myoglobin and surface-bound antibody. 相似文献
55.
Mayu Muramatsu Yoshihisa Harada Takayuki Suzuki Hiroyuki Niino 《Advanced Composite Materials》2016,25(2):143-158
In this study, the correlation between the stress–strain behavior of a carbon fiber-reinforced plastic (CFRP) and the temperature at which the heat-affected zone (HAZ) is generated is investigated. First, CFRP ([?45/45]2s laminate) specimens were heated at several temperatures to induce thermal damage, i.e. a HAZ. Subsequently, tensile tests were conducted on the specimens with thermal damage. Then, microscopy and X-ray measurements were carried out to discuss the stress–strain responses from a microscopic viewpoint. The results of strain measurement during thermal treatment indicated that the strain increases with increasing temperature. The tensile tests showed that the CFRP specimens subjected to thermal damage during heating at a high temperature fractured in the ductile mode, whereas the fracture mode of the CFRP specimens with low-temperature thermal damage was discontinuous. Microstructure observation using X-ray tomography showed that the debonding between the carbon fibers and the resin matrix induced by heating to above the glass transition temperature was responsible for the continuous fracture mode. 相似文献
56.
浸没式光刻的优势和可行性 总被引:3,自引:2,他引:3
SoichiOwa HiroyukiNagasaka 《电子工业专用设备》2004,33(2):10-14,18
浸没式光刻通过高折射率的液体充入透镜底部和片子之间的空间使光学系统的数值孔径具有显著的优势。在193nm曝光系统中,水(折射率为1.44)被选作最佳的浸入液体。通过成像模拟,现已证明ArF穴193nm雪浸没式光刻(NA=1.05~1.23)与F2穴157nm雪干法穴NA=0.85~0.93雪光刻具有几乎相同的成像性能。结合流体力学和热模拟结果,讨论了ArF浸没式曝光设备的优势和可行性。 相似文献
57.
Tomohiko Makiyama Takashi Obama Yuichi Watanabe Hiroyuki Itabe 《International journal of molecular sciences》2022,23(12)
Lipid droplets (LDs) are intracellular organelles that are ubiquitous in many types of cells. The LD core consists of triacylglycerols (TGs) surrounded by a phospholipid monolayer and surface proteins such as perilipin 2 (PLIN2). Although TGs accumulate in the phospholipid bilayer of the endoplasmic reticulum (ER) and subsequently nascent LDs buds from ER, the mechanism by which LD proteins are transported to LD particles is not fully understood. Sar1 is a GTPase known as a regulator of coat protein complex Ⅱ (COPⅡ) vesicle budding, and its role in LD formation was investigated in this study. HuH7 human hepatoma cells were infected with adenoviral particles containing genes coding GFP fused with wild-type Sar1 (Sar1 WT) or a GTPase mutant form (Sar1 H79G). When HuH7 cells were treated with oleic acid, Sar1 WT formed a ring-like structure around the LDs. The transient expression of Sar1 did not significantly alter the levels of TG and PLIN2 in the cells. However, the localization of PLIN2 to the LDs decreased in the cells expressing Sar1 H79G. Furthermore, the effects of Sar1 on PLIN2 localization to the LDs were verified by the suppression of endogenous Sar1 using the short hairpin RNA technique. In conclusion, it was found that Sar1 has some roles in the intracellular distribution of PLIN2 to LDs in liver cells. 相似文献
58.
Numerical results of three-dimensional separated flow and heat transfer in a rectangular channel with a suddenexpansion are presented in this paper.Numerical simulations of Navier-Stokes and energy equations are carriedout using the finite difference method.The results of three-dimensional calculations are compared with thetwo-dimensional ones,and effects of the aspect ratio of channel upon the flow are shown.The transition fromsymmetric to asymmetric flow appears at lower Reynolds number as increasing the aspect ratio.The details oflocal heat transfer characteristics in two different separated flow regions on two downstream walls are clarified.Two-dimensionality of the flow and heat transfer almost disappears for the aspect ratio considered. 相似文献
59.
Sanshiro Kanazawa Hiroyuki Okada Dan Riu Yo Mabuchi Chihiro Akazawa Junichi Iwata Kazuto Hoshi Atsuhiko Hikita 《International journal of molecular sciences》2022,23(15)
It is well known that the properties of hematopoietic stem/progenitor cells (HSCs), such as their self-renewal ability and multipotency, are maintained through interactions with mesenchymal stem/stromal cells (MSCs). MSCs are rare cells that are present in the bone marrow and are useful for clinical applications due to their functional ability. To obtain the necessary number of cells, MSCs must be cultured to expand, but this causes a remarkable decrease in stem cell properties, such as multipotency and proliferation ability. In this study, we show that the c-Mpl signal, which is related to the maintenance of hematopoietic stem cells, has an important effect on the proliferation and differentiation ability of MSCs. Utilizing a co-culture system comprising MSCs and HSCs, it is suggested that signaling from hematopoietic cells to MSCs supports cell proliferation. Interestingly, the enhanced proliferation ability of the HSCs was decreased in c-Mpl knock-out HSCs (c-Mpl-KO). In addition, the MSCs co-cultured with c-Mpl-KO HSCs had reduced MSC marker expression (PDGFRa and Sca-1) compared to the MSCs co-cultured with c-Mpl-wild-type HSCs. These results suggest that a hematopoietic–mesenchymal signal exists, and that the state of the HSCs is important for the stability of MSC properties. 相似文献
60.
Behaviormetrika - Brand switching data among 12 margarine brands were analyzed by the asymmetric multidimensional scaling based on the singular value decomposition. A two-dimensional result was... 相似文献