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51.
基于TCP的单终端系统可用带宽测量工具abget,采用类似SLOPS的方法,具有较好的实用性。但这种方法收敛速度慢,测试流较多,对背景流会产生较大影响。结合近几年来的研究成果,将双终端系统中的测量方法引进单终端系统中,对abget探测包串发送速率的调整方法和单向时延趋势的判断算法进行了改进。改进后的方法较原方法提高了测量准确性,加快了测量的收敛时间。 相似文献
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The fine granular area (FGA) plays a crucial role in the VHCF regime. However, so far, the uniform understanding or conclusion about the formation mechanism of FGA has not been drawn. In view of the significance of FGA, the current studies on FGA, i.e., the FGA size, the stress intensity factor range at the periphery of FGA, the crack initiation and growth process in FGA, and the formation mechanisms of FGA, are reviewed in the present paper. The role of internal hydrogen in the VHCF regime is further discussed. In the end, two important definite conclusions are drawn based on the present investigations. 相似文献
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《Food Control》2016
Recent outbreaks with fresh produce have raised questions regarding management of quality and safety in the complex supply chains, where cooperatives play a central role. The overall objective of this article was to investigate the role of cooperatives in food quality and safety management in the fresh produce chain, focussing on the food safety management systems implemented on the farms. More specifically, we raise the question how a more market-like or a more hierarchy-like governance of transactions via cooperatives affect the quality and safety management system of the members. The research employed case studies in four cooperatives in Belgium and the Netherlands, each with different size and per cent of contractual sales. Data was collected with a diagnostic tool for assessment of food safety management systems (FSMS) on the farms, and semi-structured interviews with the quality assurance managers of the cooperative firms. Twenty-eight strawberry farms were assessed with the diagnostic tool, seven per each cooperative. Cooperatives play a double role in managing quality and safety in the food supply chain. They are responsible for the supply chain management, including tactical decisions about coordination of quality and safety requirements between customers, cooperative firms and their farmers. At the same time, they are selling the products of their members and make strategic decisions about the governance of transactions in the supply chain, which ultimately may have an impact on the supply chain management and the FSMS on the farms. Farmers in cooperatives with more hierarchical relationships showed better operation of control activities (score 3), and advanced assurance activities at score 4 (advanced level), more science-based, adapted and tested for their effectiveness. This was associated with more effort put in supply chain management by the cooperative to support collaboration and coordination in the chain. However, the largest cooperative had moderate scores for several key control functions, suggesting that large cooperatives with complex business functions may suffer from lower commitment of members, leading to lower FSMS performance at farms. 相似文献
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Huiping Hu Jianxiong Hao Yongqiang Cheng Lijun Yin Yanli Ma Zhenwei Yu Lite Li 《International Journal of Food Science & Technology》2012,47(4):689-695
A low‐salt (4% NaCl, w/w) douchi supplemented with different concentration of fermented rice culture (FRC) of 0%, 5%, 10%, 15% and 20% (v/w) was produced, and the effect of FRC on microbiology, biochemistry and sensory quantity was investigated. Results indicated that FRC had a significant effect on low‐salt douchi. Compared with the control (added 0% FRC), in the other treatments, the counts of yeast and lactic acid bacteria increased by about 50%, whereas the moulds decreased by about 30%; the pH reduction was close to 4.7; total acid increased to about 1.300 g per 100 g; reducing sugar maintained a decrease to 21.07 mg per g; amino nitrogen increased to about 0.900 g per 100 g, but not above the control (1.013 g per 100 g). In general terms, total free amino acid contents and three organic acids were higher in low‐salt products than four commercial products. Sensory evaluation of products supplemented with 10% and 15% FRC revealed better overall acceptability compared with other treatments and a commercial product. 相似文献
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光学层析成像是一个病态重建过程,为降低重建过程中的病态特性,需加入合适的先验信息。目前,大多数重建都是基于扩散方程的,在某些情况下,这种重建会失败。直接基于玻耳兹曼传输模型,并以图像熵为正则化项的梯度迭代重建是一种有效的方法。该方法中,梯度计算是个难点。对此,提出一种基于梯度树的求解方法,降低光学层析图像重建的病态性,有效地重建光学层析图像。 相似文献
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采用不同的工艺调控技术,实现了一种成分体系可生产具有不同屈强比的经济型冷轧DP780钢,并通过分析力学性能测试结果、TEM和SEM组织形貌特征,得到热轧初始组织、冷轧压下量、连续退火工艺对屈强比的影响。结果表明,当热轧初始组织为F+P(铁素体+珠光体)时,随着平均晶粒尺寸细化至约7.5 μm,屈服强度增加了50 MPa,屈强比由0.48增至0.56;当热轧初始组织变为F+B(铁素体+贝氏体)、以贝氏体为主时,屈服强度达到532 MPa,屈强比增至0.65,同时有利于保证DP780钢的扩孔性和塑性,扩孔率达到86%,特别适用于有扩孔翻边要求的汽车结构件和加强件。此外,适当增加冷轧压下量和降低退火保温温度,均有利于增强基体的强化效应,从而提高屈强比。 相似文献