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31.
JOHANNA C.M. JACOBS† JACQUES H. HOUBEN† TON VAN VLIET‡ PIETER S. VAN ROON† BEREND KROL† 《International Journal of Food Science & Technology》1994,29(3):321-329
A specially designed tube viscometer was used to measure apparent viscosity during flow of Bologna type sausage emulsions moving through a pipe. Emulsions varied in fat content (from 21.8 to 44.3%) and in moisture/protein ratio (from 3.7 to 5.6), and the effects of added sodium chloride, sodium diphosphate, starch and blood plasma were investigated in a 36% fat, 3.7 moisture/protein emulsion.
The shear stresses determined as a function of shear rate were fitted by a power law. Yield stress of the emulsions was negligible relative to the applied stress. However, inspection of the flow profiles indicated that considerable slip of the sausage emulsion occurred at the pipe wall. Both emulsion flow and slip contribute to overall flow behaviour, so a kind of effective viscosity is determined. Intrinsic rheological properties and wall slip will both be affected by the composition of the sausage emulsion. 相似文献
The shear stresses determined as a function of shear rate were fitted by a power law. Yield stress of the emulsions was negligible relative to the applied stress. However, inspection of the flow profiles indicated that considerable slip of the sausage emulsion occurred at the pipe wall. Both emulsion flow and slip contribute to overall flow behaviour, so a kind of effective viscosity is determined. Intrinsic rheological properties and wall slip will both be affected by the composition of the sausage emulsion. 相似文献
32.
从RS—232C,RS—422接口标准及RS—232C与RS—422的电平转换等方面详细地介绍非线性设备与编辑录像机遥控部分的硬件接口技术,给出了相关的电路原理图,指出了使用时的一些注意事项。 相似文献
33.
本文从糖甙类化合物的数据特点出发,用较严格的数学推导总结出原则上适用于任何类型的~(13)C-NMR 图谱化学位移范围规律计算机自动解析的方法,并从多方面说明了该方法的研究及实现对实际的~(13)C-NMR 图谱解析工作的意义和重要作用。 相似文献
34.
Shumin Zhai Jing Kong Xiangshi Ren 《International journal of human-computer studies》2004,61(6):823-856
Pointing tasks in human–computer interaction obey certain speed–accuracy tradeoff rules. In general, the more accurate the task to be accomplished, the longer it takes and vice versa. Fitts’ law models the speed–accuracy tradeoff effect in pointing as imposed by the task parameters, through Fitts’ index of difficulty (Id) based on the ratio of the nominal movement distance and the size of the target. Operating with different speed or accuracy biases, performers may utilize more or less area than the target specifies, introducing another subjective layer of speed–accuracy tradeoff relative to the task specification. A conventional approach to overcome the impact of the subjective layer of speed–accuracy tradeoff is to use the a posteriori “effective” pointing precision We in lieu of the nominal target width W. Such an approach has lacked a theoretical or empirical foundation. This study investigates the nature and the relationship of the two layers of speed–accuracy tradeoff by systematically controlling both Id and the index of target utilization Iu in a set of four experiments. Their results show that the impacts of the two layers of speed–accuracy tradeoff are not fundamentally equivalent. The use of We could indeed compensate for the difference in target utilization, but not completely. More logical Fitts’ law parameter estimates can be obtained by the We adjustment, although its use also lowers the correlation between pointing time and the index of difficulty. The study also shows the complex interaction effect between Id and Iu, suggesting that a simple and complete model accommodating both layers of speed–accuracy tradeoff may not exist. 相似文献
35.
集成电路的现状及其发展趋势 总被引:5,自引:0,他引:5
集成电路是信息社会经济发展的基石。通过对集成电路发展规律的分析,从集成电路的设计、制造、新产品研发和市场动态等方面,描述了集成电路的最新动态;探讨了集成电路的发展趋势;指出集成电路与其它学科、技术的结合,不断形成新的研究方向;新材料、新结构、新器件不断涌现,特征尺寸继续缩小,摩尔定律仍然起作用。 相似文献
36.
37.
Bong-Un Lee Hwa-Suk Oh Ja-Young Kang 《Journal of Mechanical Science and Technology》2007,21(3):436-447
The geometric singularity problem is one of principal difficulty when using single-gimbal control moment gyros as spacecraft
attitude control devices. To overcome singularity, new steering logics are suggested in this paper which results in a reduction
in the difficulty of generating gimbal rates around a singular state. One of the suggested steering laws presented is the
reduced dimensional singular value decomposition steering law, which adopts the singular value decomposition in reduced dimensional
forms. Two other steering laws make use of the least square method in reduced dimensional forms. All of the suggested steering
laws have been generated for the compensation of the torque insufficiency. These logics are verified mathematically and simulations
at a singular condition and non-singular condition are performed to see how well they work. 相似文献
38.
基于斜坡的工程地质测绘和实验室分析,总结了研究地段区域滑坡规律,引入粘弹性基础板的弯曲破坏原理,对该地段斜坡破坏机制进行分析。从岩体本身的质量和岩体在地球内外营力作用下所表现的自稳性两方面考虑,采用两级模糊综合评判理论对测区进行斜坡稳定性工程地质单元划分,并利用刚体平衡理论验证模糊评判结果。 相似文献
39.
现场地质预测与决策技术 总被引:1,自引:1,他引:0
油气的生成、运移、分布、成藏、保存具有规律性,技术人员可以依据其规律性对地下地质情况进行推理、预测和决策。钻井过程的现场地质预测技术方法主要是外推法、因果法和直观法三大类。外推法是常用的预测方法,包含了岩性、沉积旋回、标志层、标准层、重矿物等岩石地层学对比方法和生物地层学方法及地球物理方法。现场地质预测与决策是通过确定预测目标、收集相关资料、进行对比分析、形成地质预测结果、拟定地质决策方案、方案优选、方案实施等环节来完成。该技术是现场地质监督的核心技术,在实践中取得显著成效。 相似文献
40.
Local stress and strain variations in the deformation zone can be ascertained by measuring hardness. Hardness is correlated
with strain and stress. The expressions discussed later are useful in determining the local variations in stress and strain
from hardness measurement. It is a simple method compared to visioplasticity. One can estimate the forces required for a forming
process. It helps in the choice of equipment, design of tooling and selection of lubricant for the particular process. 相似文献