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An explosion on the ground surface can cause considerable damage to underground structures. In this study, a series of experimental and numerical investigations were conducted to examine the performance and reinforcing mechanism of reinforced soil subjected to blast loads. An excavated pit backfilled with sand only (unreinforced soil) and sand reinforced with three layers of geotextiles (reinforced soil) were used as test models in a field explosion test. In the field explosion test, blast pressures in air and soil, ground deformation, and mobilized reinforcement tensile strain were measured. The test results obtained for the reinforced and unreinforced soil were compared to evaluate the effectiveness of using soil reinforcement as a protective barrier against blast loads. The test results indicated that peak blast pressure in the reinforced soil was only 10–28% of those in the unreinforced soil. Two reinforcing mechanisms were identified in this study: the tensioned membrane effect and lateral restraint effect. Moreover, a series of numerical analyses were performed to evaluate the effects of reinforcement parameters on the blast pressure. This study provides useful insights into the application and design of soil reinforcement as an alternative antiexplosion measure to protect underground structures against surface explosions. [ABSTRACT FROM AUTHOR]

Supplier selection is an essential issue, particularly, for semiconductor manufacturing. Nowadays, since high demands in the globally competitive semiconductor manufacturing environment, multiple-line processes are quite commonly applied. In the paper, we consider a two-stage method composing of quality verification and selection decision for multiple-line supplier selection problems. Since quality performance is an important criterion in supplier selection, we test whether the new supplier has a significantly better capability than the existing supplier based on the multiple-line yield index in the stage of quality verification. In selection decision, when the magnitude of capability outperformance is significant, switching contracts to a new entrant supplier is suggested. In addition, analytical closed-form solutions for asymptotical critical values and required sample sizes are derived and tabulated for the investigated multiple-line supplier selection problem. We demonstrate the applicability of the proposed supplier selection method by presenting a real-world example taken from a semiconductor packaging shop floor located in the Science-based Industrial Park in Hsinchu, Taiwan. [ABSTRACT FROM AUTHOR]

The spintronics applications long anticipated for topological insulators (TIs) has been hampered due to the presence of high density intrinsic defects in the bulk states. In this work we demonstrate the back-gating effect on TIs by integrating Bi2Se3 films 6–10 quintuple layer (QL) thick with amorphous high-κ oxides of Al2O3 and Y2O3. Large gating effect of tuning the Fermi level EF to very close to the band gap was observed, with an applied bias of an order of magnitude smaller than those of the SiO2 back gate, and the modulation of film resistance can reach as high as 1200%. The dependence of the gating effect on the TI film thickness was investigated, and ΔN2D/ΔVg varies with TI film thickness as ~t–0.75. To enhance the gating effect, a Y2O3 layer thickness 4 nm was inserted into Al2O3 gate stack to increase the total κ value to 13.2. A 1.4 times stronger gating effect is observed, and the increment of induced carrier numbers is in good agreement with additional charges accumulated in the higher κ oxides. Moreover, we have reduced the intrinsic carrier concentration in the TI film by doping Te to Bi2Se3 to form Bi2TexSe1–x. The observation of a mixed state of ambipolar field that both electrons and holes are present indicates that we have tuned the EF very close to the Dirac Point. These results have demonstrated that our capability of gating TIs with high-κ back gate to pave the way to spin devices of tunable EF for dissipationless spintronics based on well-established semiconductor technology. [ABSTRACT FROM AUTHOR]

Single crystal ferromagnetic Fe3Si(111) films were grown epitaxially on GaAs(111)A by molecular beam epitaxy. These hetero-structures possess extremely low surface roughness of 1.3 Å and interfacial roughness of 1.9 Å, measured by in-situ scanning tunneling microscope and X-ray reflectivity analyses, respectively, showing superior film quality, comparing to those attained on GaAs(001) in previous publications. The atomically smooth interface was revealed by the atomic-resolution Z (atomic number)-contrast scanning transmission electron microscopy (STEM) images using the correction of spherical aberration (Cs)-corrected electron probe. Excellent crystallinity and perfect lattice match were both confirmed by high resolution x-ray diffraction. Measurements of magnetic property for the Fe3Si/GaAs(111) yielded a saturation moment of 990 emu/cm³ with a small coercive field ≤1 Oe at room temperature. [ABSTRACT FROM AUTHOR]

Objective: To evaluate how the different processing methods cryopreservation and dehydration affect the structural integrity and biological composition of key signalling molecules within amniotic membrane and umbilical cord tissues. Method: We directly compared cryopreserved amniotic membrane (AM) and umbilical cord (UC) tissues with dehydrated amniotic membrane/chorion (dHACM) tissue using biochemical and functional assays including histological and histochemical staining, BCA, agarose gel electrophoresis, western blot, ELISA, and proliferation and cell death assays. Results: Cryopreservation retains the native architecture of the AM/UC extracellular matrix and maintains the quantity and activity of key biological signals present in fresh AM/UC, including high molecular weight hyaluronic acid, heavy chain-HA complex, and pentraxin 3. In contrast, dehydrated tissues were structurally compromised and almost completely lacked these crucial components. Conclusion: The results presented here indicate that cryopreservation better preserves the structural and biological signaling molecules of foetal tissues. [ABSTRACT FROM AUTHOR]