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1.
Non-conventional mashing conditions are relevant in the development of a lactic acid-fermented soymilk beverage where mashed rice is the source of carbohydrates for the fermentation and sweetness of the beverage. Advantages in the process layout could be achieved by mashing at higher pH and lower malt concentrations than normally used in the brewing industry. the work reported here assessed the consequences of mashing under non-conventional conditions. Malt concentration in the cereal part was varied from 25% to 70% (w/w), pH was varied within 5.3 to 7.1, and prolongation of the holding times at 50°C and 62°C was investigated. Regression equations have been established for predicting yields of soluble protein, low molecular weight sugars and total fermentability as functions of pH and malt concentration. the results showed that the maltose yield was constant while glucose, maltotriose and total fermentable sugar yields decreased slightly with increasing pH and decreasing malt concentration. Prolonged mash holding times at 50°C and 62°C gave minor increases in protein yields only. It is concluded that it is quite acceptable to use non-conventional mashing conditions when a mashing step is integrated in other food processes.  相似文献   
2.
Software structure is the most important factor affecting the quality of a program.The evaluation of software structure is a foundational technique for software development.However,the traditional evaluation criteria,such as "high cohesion and low coupling",are no longer appropriate for the new web applications,which are designed with a hierarchical framework.A novel approach is proposed in this paper to evaluate software quality based on the interaction and encapsulation of methods.In particular,two criteria for high quality software,the functional and hierarchical structure,are proposed to support widely used web applications.The cohesion and coupling and layer matching ratios between methods within a software package are calculated to determine whether the package is well implemented in terms of functional or hierarchical structure.This approach enables us to quantify the quality of a software system according to the structural types of its packages.Experiments were carried out on 18 versions of Struts and six open-source software packages.Our evaluation concurs with the intuition that minor upgrades,aimed at fixing bugs and adding minor functionality quickly,reduce software quality,whereas major upgrades,which normally clean up messy code and re-construct the software,improve software quality.  相似文献   
3.
An extended product multi-sensor cardinalized probability hypothesis density (PM-CPHD) filter for spatial registration and multi-target tracking (MTT) is proposed. The number and states of targets and the biases of sensors are jointly estimated by this method without the data association. Monte Carlo (MC) simulation results show that the proposed method (i) outperforms, although computationally more expensive than, the extended multi-sensor PHD filter which has been proposed for joint spatial registration and MTT; (ii) outperforms the multi-sensor joint probabilistic data association (MSJPDA) filter which is also extended in this study for joint spatial registration and MTT when the clutter is relatively dense.  相似文献   
4.
Tensor interpolation is a key step in the processing algorithms of diffusion tensor imaging (DTI), such as registration and tractography. The diffusion tensor (DT) in biological tissues is assumed to be positive definite. However, the tensor interpolations in most clinical applications have used a Euclidian scheme that does not take this assumption into account. Several Rie-mannian schemes were developed to overcome this limitation. Although each of the Riemannian schemes uses different metrics, they all result in a ‘fixed’ interpolation profile that cannot adapt to a variety of diffusion patterns in biological tissues. In this paper, we propose a DT interpolation scheme to control the interpolation profile, and explore its feasibility in clinical applications. The profile controllability comes from the non-uniform motion of interpolation on the Riemannian geodesic. The interpolation experiment with medical DTI data shows that the profile control improves the interpolation quality by assessing the reconstruction errors with the determinant error, Euclidean norm, and Riemannian norm.  相似文献   
5.
Underground contamination by non-aqueous phase liquids (NAPLs) becomes increasingly serious. Rapid and reliable detection of contaminated zone and degree is the first step to site remediation. In this paper, diesel and fine sand are used as experiment materials to investigate the applicability of using time-domain reflectometry (TDR) to detect LNAPLs contamination. The major work includes: measurement of dielectric constant and electrical conductivity for the diesel-water-air-sand mixtures; measurement of reflection waveform and dielectric constant for specimens with a diesel contaminated layer being sandwiched in sand. The experimental results show the followings: A significant decrease in both dielectric constant and electrical conductivity is observed for the diesel-water-air-sand mixtures when diesel displaces the pore water, and the content of diesel can be calculated by the model; insignificant change in dielectric properties is measured when diesel only displaces the pore gas; when the diesel contaminated sand is sandwiched between two saturated sand layers, the interfaces of the diesel contaminated layer can be identified by analyzing the reflection waveform; for field application, TDR method is valid for the case that LNAPLs seep into saturated sand layer, and the applicability of TDR method in vadose zone depends on the initial saturation of the sand layer. The findings obtained in this paper provide a guidance for the use of TDR for the field investigation of NAPLs contaminated site.  相似文献   
6.
稳定的Born近似叠前深度偏移方法   总被引:21,自引:2,他引:19  
本文针对HuangLJ等(1999)在“扩展的局部Born Fourier偏移方法”一文中提出的散射波场计算公式在强横向变速介质的不稳定性,提出了一种新的Born近似散射场计算公式,并把该公式应用于波场递归于推过程中,进而得到一种稳定的Born近似叠前深度偏移方法。与Split-Step Fourier方法和Phase-Screen方法相比,本方法对Marmousi模型炮集数据的偏移处理取得了良好的结果。本文提出了的Born近似散射场计算公式可扩大Born近似的应用范围,对散射波扬的计算有一定的理论意义应用价值。  相似文献   
7.
西非深水钻井含油钻屑清洗方法室内研究   总被引:2,自引:0,他引:2  
针对目前西非深水钻井现场产生大量含油钻屑的情况,选取表面活性剂清洗法清除钻屑表面的油污,使其达到环境保护的要求。通过室内实验,清洗剂选用ABS或ABSN,清洗搅拌时间为15 min;使用油基钻井液的岩屑处理方案为:淡水+0.5%ABS或海水+0.5%ABS+0.1%三聚磷酸钠,可将钻屑含油量降至2%以下,达到西非海域就地排放钻屑的要求。结合现场情况,确定采用振动式钻屑清洗机与LWTU污水处理系统,并制定了海上钻屑处理工艺流程。  相似文献   
8.
根据热力学原理,文章认为建筑师需要通过不同的语汇和实践使建筑更趋向开放的、远离(热力学)平衡状态的系统,而不是仅仅追求节能规范、建筑模拟或建筑认证。  相似文献   
9.
王智  罗彦  韩中合  安连锁 《动力工程》2012,(12):934-940
基于冠状成核机理,建立了湿蒸汽两相非均质凝结流动数值模型,对缩放喷管、汽轮机叶栅和汽轮机级内湿蒸汽两相非均质凝结流动进行了数值模拟.结果表明:与自发凝结相比,非均质凝结流动中杂质颗粒改变了凝结过程;杂质颗粒减小了喷管中凝结激波强度,改变了汽轮机叶栅中的压力分布,降低了蒸汽过冷度,减少了不平衡热力学损失;在汽轮机级内,非均质凝结流动的动、静叶进、出口汽流角接近过热蒸汽流动的动、静叶进、出口汽流角,其动叶前压力高于过热蒸汽的动叶前压力,但级反动度偏离过热蒸汽流动数值.  相似文献   
10.
石英砂与树脂覆膜砂实验渗透率影响因素分析   总被引:1,自引:0,他引:1  
在出砂气藏,支撑剂对其开采有着至关重要的作用,而渗透率又是支撑剂重要性能。石英砂和树脂覆膜砂有着不同渗透率,主要通过室内实验方法研究,分别用气测和液测它们的渗透率。气测时,改变气体的流速,分析不同流速和不同时间对渗透率的影响。液测时,分别在不定轴向压力下改变液体流速,稳定轴向压力下改变液体的流速,分析轴向压力、流速以及不同时间对渗透率的影响。该研究对深入了解油气藏的开发动态和采收率具有一定意义。  相似文献   
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