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61.
The aim of this paper is two fold. First we investigate the three different types of systems, namely cellular layout (CL), process layout (PL) and virtual cells (VCs). VCs are addressed by using family-based scheduling rule, developed by a part allocation algorithm in a PL. Simulation is used to compare three types of systems under the performance metrics such as mean flow time and mean tardiness. Results indicate that VCs have better responsiveness in terms of the performance metrics. Second we develop a new ant colony optimization-based metamodels fed by existing simulation runs to represent the prospective simulation runs, which require a lot of time and effort. Regression metamodels, which allow us to obtain much faster results, are seen to be promising to estimate the systems behaviors.  相似文献   
62.
The special interaction between 3-aminophenylboronic acid and monosaccharides, particularly glucose, fructose and galactose, has been investigated and used for the development of electrochemical and surface plasmon resonance (SPR) based saccharide sensors. The binding constants and thermodynamic parameters of interaction such as free energy of binding (ΔG), enthalpy (ΔH) and entropy (ΔS) were determined for the first time using isothermal titration calorimetry revealed the enthalpic and entropic contributions to the free energies of binding. Effects of pH and buffer on the binding constants (k) between 3-aminophenylboronic acid and monosaccharides were also examined. The binding constant of fructose was found to be six times higher than glucose and four times higher than galactose at pH 11, leading the specific detection of fructose. SPR and potentiometric calibration for fructose were linear in the concentration range of 10–120 mM and 8–84 mM, respectively. Limit of detection of the SPR and potentiometric method were found to be as 8.9 mM and 1.4 mM, respectively.  相似文献   
63.
手势识别作为人和机器之间重要的交互手段,在日常生活中具有广泛的应用场景。基于无线信号特别是WiFi的手势识别由于其无接触、成本低等优点成为当前热门的方式。为解决传统基于无线信号手势识别算法没有充分利用信号相位特征的缺点,本文提出利用WiFi信道状态信息幅值和相位结合的方式进行手势识别。通过子载波降维和动作曲线提取对接收的WiFi信号进行处理,并将信号的幅值和相位结合,利用机器学习算法对数据进行训练和分类,实现了单手向前、单手向后、单手向左、单手向右、单手向上和单手向下六种手势的识别。实验结果显示,本文算法在近距离和远距离下的精确度分别为96%和92%。  相似文献   
64.
New types of reactive UV absorbers for applications to cellulose textiles have been prepared. These substances are condensation products of sulfobenzimidazolaniline, cyanuric chloride, and aminophenyl‐(2‐sulfethoxy)‐sulfone. They were applied to bleached, unbleached, as well as dyed cellulose textiles with the aim to increase the protection effect of these textiles against UV radiation. All the tested textiles showed a marked increase in the UV protection factor (UPF). The effects of the UV absorbers tested neither interfere with the function of fluorescent brighteners (FBs) nor affect the hue of the used dyestuffs. They exhibit synergistic effect in the protection effectiveness against UV radiation: the UV absorbers used together with dyestuffs and FBs have a higher UPF factor than is the sum of UPF contributions of the individual components. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
65.
66.
Diabetic nephropathy (DN) is the most frequent cause of chronic renal failure. Until now, the pathophysiological mechanisms that determine its development and progression have not yet been elucidated. In the present study, we evaluate the role of autophagy at early stages of DN, induced in type 2 diabetes mellitus (T2DM) mouse, and its association with proximal tubule membrane endocytic receptors, megalin and cubilin. In T2DM animals we observed a tubule-interstitial injury with significantly increased levels of urinary GGT and ALP, but an absence of tubulointerstitial fibrosis. Kidney proximal tubule cells of T2DM animals showed autophagic vesicles larger than those observed in the control group, and an increase in the number of these vesicles marked with LBPA by immunofluorescence. Furthermore, a significant decrease in the ratio of LC3II/LC3I isoforms and in p62 protein expression in DN affected animals is shown. Finally, we observed a marked increase in urinary albumin and vitamin D binding-protein levels in T2DM animals as well as a significant decrease in expression of megalin in the renal cortex. These results indicate an alteration of the tubular endocytic transporters in DN, which could be related to autophagic dysfunction, which would in turn result in impaired organelle recycling, thus contributing to the progression of this disease.  相似文献   
67.
The step-flow growth condition of Si on Si(111) near the (7×7)-"1×1" surface phase transition temperature TC are analyzed within the framework of Burton--Cabrera--Frank theory. In particular, coexistence of both surface phases well below TC and their specific influence on the step-flow growth behavior are considered. We presume that under dynamical condition of growth, the surface initially covered by only the (7×7) phase separates into domains surrounded by "1×1" areas. On such a surface, the overall supersaturation should be reduced drastically compared to a surface with only (7×7), resulting in much larger critical terrace width for nucleation.  相似文献   
68.
Magnetization and resistivity measurements have been carried out on the equiatomic ternary compound NdNiSn in the temperature range 2–200 K. The compound crystallizes in the orthorhombic CeNiSn-type structure with space group Pna21. Magnetic susceptibility shows a distinct feature at TN=3 K (Néel temperature), typical of a phase transition from an antiferromagnetic to paramagnetic state. In the paramagnetic regime, the magnetic susceptibility obeys Curie–Weiss behavior yielding an effective magnetic moment μeff=3.32μB at lower temperatures, and 3.88 μB at higher temperatures. The reduction in the magnetic moment at lower temperatures is attributed to a crystalline electric field (CEF) effect, while the slight excess of magnetic moment at high temperatures compared to that of the free Nd3+ ion (3.62 μB) indicates that only a very small magnetic moment, at most 0.3 μB, is induced at the Ni sites. The electrical resistivity exhibits metallic behavior and no anomaly is observed at the respective Néel temperature. Analysis of the resistivity data in terms of crystalline electric fields including s–d electron scattering reveals that the ground magnetic state for the Nd3+ ions is a doublet of J=±5/2 states, with a first exited doublet of J=±7/2 states having an energy splitting of 56 K, with the next exited multiplet 139 K above the ground levels. These results are in fairly good agreement with those reported in the literature based on magnetic susceptibility and heat capacity measurements.  相似文献   
69.
食用菌营养丰富,是优质蛋白质的潜在来源。本研究以18个常见食用菌品种为研究对象,分析了食用菌中的水分、灰分、蛋白、总糖和L-麦角硫因等营养成分,并采用顶空固相微萃取结合气相色谱-质谱联用法(HS-SPME-GC-MS)分析了其中6种食用菌子实体、菌丝体及发酵液的风味物质。结果表明,18种食用菌水分含量为6.7~13.77 g/100 g、灰分含量为2.24~10.9 g/100 g、脂肪含量为0.3~2.92 g/100 g、总糖含量为2.11~10.5 g/100 g。粗蛋白含量在7.88~35.87 g/100 g之间,其中双孢菇的蛋白质含量高达35.87 g/100 g。氨基酸种类齐全、含量丰富且含有人体必需的8种必需氨基酸。主成分分析表明香菇、黑木耳、灰树花、草菇和金针菇等食用菌的氨基酸组成比例与鸡蛋最相似,但与肉类、大豆和小麦等氨基酸组成相差较大。高效液相色谱结果表明香菇中富含麦角硫因,含量高达336 mg/kg,且灰树花、羊肚菌、双孢菇和鸡腿菇的麦角硫因含量也高于100 mg/kg。HS-SPME-GC-MS在6种食用菌中共鉴定出34种主要挥发性化合物,包括醛类、酮类、酯类、醇类、酚类、醚类、烷烃类和杂环化合物。灵芝菌丝体富含己醛、甲基壬基甲酮、反-2-辛烯醛、2-正戊基呋喃、2,4-壬二烯醛等成分,与其他17种样品有明显差异;6种食用菌发酵液的风味物质相似,均具有庚酸乙酯、18-冠醚-6等特有风味物质;而灵芝、鸡腿菇子实体以及杏鲍菇菌丝具有2,6-二叔丁基对甲酚、苯甲酸甲酯等特有风味。本研究通过分析常见食用菌的营养成分及风味物质,为食用菌的高值化开发提供了数据基础。  相似文献   
70.
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