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141.
3D integration provides a promising solution to achieve system level integration with high function density, small form factor, enhanced transmission speed and low power consumption. Stacked bonding is the key technology to enable the communication between different strata of the 3D integration system. Low temperature bonding approaches are explored in industry to solve the performance degradation issue of the integrated devices. In this paper, various low temperature bonding technologies are reviewed and introduced, as well as the latest developments in world-wide companies and research institutes. The outlook for industrial application is also addressed in the paper. 相似文献
142.
Hwa Jung Kim Jeongah Ko Charlotte Storni Hong Ji Song Young Gyu Cho 《Journal of Functional Foods》2012,4(1):287-293
Overweight and obesity have become a global epidemic and they may impair health. Traditional use and growing evidence indicate that mate (Ilex paraguariensis A. St.-Hil.) may be helpful in losing excessive weight and fat. The present randomized, double-blind, placebo-controlled study evaluated efficacy and safety of an extract from green mate in 60 overweight subjects aged 20–39 years during 6-weeks. Body composition was measured by Dual-Energy X-ray Absorptiometry (DEXA) at baseline and after 6 weeks. Body weight, body mass index (BMI), waist circumference (WC) and various safety parameters were monitored. After 6 weeks, subjects taking mate experienced a significantly greater reduction of percent of body fat (?0.3% vs. +0.6%, p = 0.04) and fat mass (?0.5 kg vs. +0.2 kg, p = 0.04) than placebo. No significant differences were observed in other measurements. No adverse events occurred and all safety parameters were within normal ranges during the study in both groups. Thus, taking green mate extract reduced body fat after 6 weeks, while the treatment was safe and well tolerated. 相似文献
143.
D. Ahmad G. C. Kim Rock-Kil Ko Yong Seung Kwon Y. C. Kim 《Journal of Superconductivity and Novel Magnetism》2014,27(8):1807-1812
Ru1Sr2Gd1Cu2O8 and Sr2Yb1Ru0.9Cu0.1O6 were synthesized using a solid-state reaction. X-ray diffraction showed that Ru1Sr2Gd1Cu2O8 crystallized into the tetragonal Ru-1212 structure (space group P4/mmm), whereas the Sr2Yb1Ru0.9Cu0.1O6 had a monoclynic structure (space group P21/n). Sr2Yb1Ru0.9Cu0.1O6 showed a possible magnetic transition ( T m a g ) at 44 K with a superconducting transition temperature T c at 30 K. In contrast, Ru1Sr2Gd1Cu2O8 showed a magnetic transition at 140 K with a T c at 25 K. The magnetization data for Sr2Yb1Ru0.9Cu0.1O6 suggests that this sample exhibits antiferromagnetic ordering in zero-field-cooled (ZFC) magnetization, whereas it reveals a weak ferromagnetic component during field-cooled (FC) cycles. In addition, larger diamagnetic signals were observed during FC cycle compared to the ZFC. These results suggest that the valence state of the Yb ion have a significant effect on the magnetic state of the Sr2Yb1Ru0.9Cu0.1O6 superconductor. 相似文献
144.
Jae Mo Yang Byung Seok Ko Chulhwan Park Byungtae Yoo Dongil Shin Jae Wook Ko 《Korean Journal of Chemical Engineering》2014,31(3):393-401
To increase awareness of safety in facilities where hazards may exist, operators, managers, and executive officers on the site should be able to monitor such facilities. However, most compressed natural gas (CNG) service stations in Korea use only local-mode monitoring, with only on-site operators to monitor the facility. To complement this local-mode monitoring, an online safety management system called Ubiquitous-gas safety management system (U-GSMS) was developed. The U-GSMS consists largely of software and hardware. The software consists of systems that can manage safety and operations, while the hardware consists of sensors installed in the gas facility and wireless communication systems using a ubiquitous sensor network (USN) technology that facilitates communication between sensors as well as between sensors and other devices. As these systems are web-based, on-site operators as well as managers and executive officers at the headquarters can more effectively and efficiently perform monitoring and safety management. 相似文献
145.
The pin power density distribution in reactor is an important quantity, necessary for the adequate assessment of fuel conditions and of core structures and pressure vessel radiation embrittlement as well.The paper shows the detailed comparison of calculated and experimentally determined pin by pin power distribution. To verify the reliability of measured data used for comparison with calculated data, the symmetrically located pins were measured. The calculations have been done with deterministic and Monte Carlo approach. The effect of different data libraries used for calculations are discussed as well. 相似文献
146.
Sung-Dae Kim Sang-Hwa Baek Tae-Yeob Kang So-Jin Park Chulju Kim Han Seo Ko 《Journal of Mechanical Science and Technology》2012,26(10):3339-3345
Thermal behaviors of combined weapon systems were analyzed by developed computational programs in this study. Also, temperature distributions of the materials of the system were measured according to the experimental conditions. Field tests that reflected the calculated thermal flow characteristics and the measured temperature distributions of the materials were prepared in a large environmental tester for the weapon systems. Boundary conditions of the analysis were the inlet and outlet conditions of the environmental tester and the low temperature limit of ?32°C. The soaking time of the system, including a fuel tank and a battery in the environmental tester, was obtained by the programs developed in this study to carry out the experiment in the predicted conditions. 相似文献
147.
A higher-order multi-scale structure for three-phase hybrid fiber-reinforced composites containing randomly located yet unidirectionally aligned circular fibers is proposed to predict effective transverse elastic moduli based on the probabilistic spatial distribution of circular fibers, the pairwise fiber interactions, and the ensemble-area homogenization method. Specifically, the two inhomogeneity phases feature distinct elastic properties and sizes. Two non-equivalent formulations are considered in detail to derive effective transverse elastic moduli of three-phase composites leading to new higher-order bounds. Numerical examples and comparisons among our theoretical predictions and other analytical predictions are rendered to illustrate the potential capability of the present method. 相似文献
148.
Anna Rzepkowska Aleksandra Ołdak Danuta Kołożyn-Krajewska 《International Journal of Food Properties》2017,20(11):2736-2747
Twenty-one strains of the genus Lactobacillus and the genus Pediococcus, isolated from Polish raw fermented meat products, were examined for the potential probiotic properties: resistance to simulated gastric and intestine conditions, safety assessment, and antimicrobial properties. Strains were resistant to gastric enzymes and low pH (3–6 log CFU/mL decrease) and intestinal enzymes and bile salts (1–3 log CFU/mL decrease). Most strains were resistant to gentamycin, streptomycin, vancomycin, tetracycline, ciprofloxacin, and kanamycin. Three of them (Lb. brevis BAL1, BAL10, and KL5) produced β-glucuronidase, which excludes them from qualifying as safe. Seven strains had the ability to produce bacteriocins or bacteriocin-like substances. Overall, strains Lb. brevis SCH6, Pd. pentosaceus BAL6, and KL14 revealed selected superior characteristics (resistance to the gastrointestinal conditions, safety assessment, and antimicrobial properties) as compared to the other LAB strains investigated, which made them a viable bioprotective culture that can be inoculated in raw fermented meat products as starter cultures. 相似文献
149.
<正>This paper presents an image resolution enhancement algorithm using spatially invariant point spread function.Point spread function is used to constrain the solution space.This parameter is computed at each iteration step using partially restored image at each iteration,and High pass filter is used to impose the degree of edge smoothness on the solution.The resulting iterative algorithm exhibits the increased PSNR better than Bicubic interpolation approach. 相似文献
150.
Won-Seok Ko Ju-Young Oh Jae-Hyeok Shim Jin-Yoo Suh Woo Young Yoon Byeong-Joo Lee 《International Journal of Hydrogen Energy》2014
Inter-diffusion between vanadium and palladium coating layers in vanadium-based hydrogen separation membranes is investigated by using a computational approach based on first-principles calculations and semi-empirical atomistic simulations, paying attention to the surface stability and the prevention of the degradation of hydrogen permeability. It is found that the governing mechanism of the inter-diffusion is the grain boundary diffusion, and therefore a diffusion barrier based on the grain boundary segregation of impurities can be an efficient way to inhibit the inter-diffusion that causes the degradation. An interesting aspect in previous experimental works that showed a good resistance to the inter-diffusion by an addition of a trace amount of yttrium is discussed from the view point of the grain boundary segregation. An experiment that proves the validity of the present alloy design scheme (inhibition of inter-diffusion using grain boundary segregation) is carried out, and a process to maximize the sustainability of the membrane is also proposed. 相似文献