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41.
This article presents a modeling and simulation method for transient thermal analyses of integrated circuits(ICs) using the original and voltage-in-current(VinC) latency insertion method(LIM). LIM-based algorithms are a set of fast transient simulation methods that solve electrical circuits in a leapfrog updating manner without relying on large matrix operations used in conventional Simulation Program with Integrated Circuit Emphasis(SPICE)-based methods which can significantly slow down the sol...  相似文献   
42.
In the present study, laminar pulsating power-law momentum and heat transfer in a uniformly heated plane duct is studied analytically. Assuming that fully developed conditions exist both hydrodynamically and thermally, a perturbation series method is utilized to derive analytical solutions for the momentum and energy balance equations, and the amplitude is prescribed as the perturbation parameter. For varying values of the power-law index ( n $n$ ), representing pseudoplastic, Newtonian, and dilatant fluids, effects of dimensionless amplitude ( ϵ $\epsilon $ ) and frequency ( F $F$ ) on periodic and period-averaged friction factor and Nusselt number are obtained. The results obtained for Newtonian fluid are shown to be in good harmony with the corresponding findings in the open literature.  相似文献   
43.
Atomically thin‐layered ReS2 with a distorted 1T structure has attracted attention because of its intriguing optical and electronic properties. Here, the direct and indirect exciton dynamics of a three‐layered ReS2 is investigated by polarization‐resolved transient photoluminescence (PL) and ultrafast pump‐probe spectroscopy. The various time scales of the decay signals of the time‐resolved PL (<10 ps), with monitoring of the populations of electron–hole pairs (exciton), and the transient differential reflectance (≈1 and 100 ps), with monitoring of the populations of electrons and/or holes in the excited states, are observed. These results reveal the characteristic exciton dynamics: rapid relaxation of direct excitons (electron–hole pairs) and slow relaxation of the momentum‐mismatched indirect excitons accompanied by a one‐phonon emission process. These findings provide important information regarding the indirect bandgap nature of few‐layered ReS2 and its characteristic exciton dynamics, boosting the understanding of the novel electronic and optical properties of atomically thin‐layered ReS2.  相似文献   
44.
The rapid growth of wireless network technology such as HSDPA and WiMAX, has lead to greater demand for access to Internet via mobile hosts. Supporting mobile connection with fast and smooth roaming across heterogeneous wireless technologies has been an important challenge over past years. In this paper, a novel multilayer scheme for QoS-aware intra-domain mobility management is proposed. The mobility support capability is embedded in key components for the domain access network, namely, the Paging Access Routers and the Mobility-support Anchor Servers (MASs). The MASs are organized in three layers; starting from the top layer Superior-MASs, Middle-MASs and Inferior-MASs, respectively. The proposed scheme identified mobility support functionality, includes intra-domain anchor specification, route optimization algorithm, intra/inter-anchor mobility support, paging and authentication management. Simulation results of the proposed scheme show fair performance especially in the presence of QoS sensitive services.  相似文献   
45.
Clean Technologies and Environmental Policy - Use of by-product materials, such as steel slag and cathode ray tube glass, as alternative recycled materials in the construction of roads, could...  相似文献   
46.
Applied Intelligence - Pixel-level anomaly localization is a challenging problem due to the lack of abnormal training samples. The existing adversarial network methods attempt to segment anomalies...  相似文献   
47.
Resistant starch (RS) can be generated through heat moisture treatment (HMT). The HMT was conducted by modifying starch using different ratio of moisture content, high temperature and heating time. A number of studies showed that the effects of HMT on RS contents in cereals, pulses, tubers and fruits were inconsistent. This study aimed to analyse the impact of HMT on RS level in various carbohydrate sources through a meta-analysis approach. Study selection was conducted with the PRISMA method. There were 21 relevant studies and 67 data used for meta-analysis. The database was analysed by using Hedges’ d. The results showed that there was a significant impact of HMT on RS level of cereals, especially wheat. The highest increase in RS levels for various carbohydrate sources in starch was influenced by the interaction of treatment between water content at 15 ≤ x < 25%, heating time at 0.25 < x ≤ 6 h and temperature at 120 ≤ x ≤ 130 °C.  相似文献   
48.
Palm fatty acid distillate (PFAD) is a rich source of vitamin E. As compared to other vegetable oil, PFAD has higher tocotrienol (70–80%) over tocopherol content, which makes it a valuable source for vitamin E extraction. Current vitamin E extraction methods are not sustainable due to the intensive usage of chemical and high operational cost. Hence, the present study investigated for the first time using dry fractionation process as a green and economical pretreatment method for separating solid fraction (stearin) and liquid fraction (olein) in order to concentrate vitamin E from PFAD in olein fraction. We examined the dry fractionation conditions: crystallization ending temperature (36–44 °C), cooling rate (0.3 and 1.5°C min−1), stirring speed (20–125 rpm), and holding time (0–60 min) on the composition of unsaturated and saturated fatty acids as well as vitamin E content in liquid fraction (olein) and solid fraction (stearin) using gas chromatography and high performance liquid chromatography, respectively. In most of these conditions, vitamin E was ultimately higher in olein fraction as compared to stearin fraction, which is correlated with the high degree of unsaturation. Under a cooling rate of 0.3°C min−1, 90 rpm stirring speed, and ending crystallization of 38 °C, the highest vitamin E rich olein fraction was attained with 1479 ± 10.51 ppm in 50 g olein fraction as compared to 1366 ± 7.94 ppm in 500 g of unfractionated PFAD.  相似文献   
49.
This study reports the influences of gamma irradiation (GI) in the range of 20–100 kGy on CuO thin films via thermal spray pyrolysis technique on the glass substrates. The results demonstrate significant influences of GI on the crystallographic, microstructural and optical characteristics of CuO thin films. The obtained XRD results showed that the crystallinity of the films deteriorates by gradually decreasing crystallite size (from 59.13 to 46 nm) as applied gamma doses increases. However, the basic monoclinic crystal structure remains same. The dislocation density and lattice strain increased with the rise of GI absorbed dose due to the creation of defects. The values of number of crystallites per unit surface area increased as dose increased indicating the abundance of crystallization of nano CuO thin films. A UV–Vis–NIR spectrophotometer was utilized to determine the optical properties and obtained results indicated that the optical energy band gap (OBG) energies reduced from 2.00 to 1.72 eV as the doses increased from 0 to 100 kGy. No distinctions of the monoclinic phase of virgin CuO thin film have been perceived under applied absorbed doses, notwithstanding the slight deterioration of the crystallinity and narrowing the OBG.  相似文献   
50.
This study aimed to determine the best lipid extraction method for infant formula; therefore, it can be used as a routine analysis. The samples were some commercial infant formulas in Indonesia. The research was conducted with three steps: (i) Lipid extraction of infant formula using five lipid extraction methods; (ii) 3-monochloropropanediol esters (3-MCPDE) and glycidyl esters (GE) analysis of lipid extract from three lipid extraction methods in the first step; and (iii) 3-MCPDE and GE analysis of six commercial infant formulas using the best lipid extraction method. The results showed that lipid extraction using the Dubois method gave the best results than other lipid extraction methods. The level of 3-MCPDE and GE also had no significant difference with the addition of NaCl in the Folch method, compared with the addition of Na2SO4. The level of 3-MCPDE and GE using the Dubois method was significantly different and higher compared with the other lipid extraction methods. 3-MCPDE and GE levels of commercial infant formula were 6.62–52.84 µg kg−1 and <1.43–17.06 µg kg−1, respectively. The values obtained were still within the standard according to Commission Regulation EU 2018/290 by the European Food Safety Authority (125 µg kg−1 for 3-MCPDE (on progress) and 50 µg kg−1 for GE).  相似文献   
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