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101.
Simplified counter-current distribution procedures are described which allow correct analysis of the α acids and iso α acids content of hop extracts. 相似文献
102.
Masoud Kayhanian Amardeep Singh Claus Suverkropp Steve Borroum 《Canadian Metallurgical Quarterly》2003,129(11):975-990
The objective of this study was to evaluate correlations between annual average daily traffic (AADT) and storm water runoff pollutant concentrations generated from California Department of Transportation (Caltrans) highway sites. Analyses of data collected from the Caltrans four-year (1997–2001) highway runoff characterization program revealed that, in general, pollutant concentrations from urban highways were higher than those found from nonurban highways. For a limited number of pollutants, however, the concentrations from nonurban highways were found to be higher than the concentrations from urban highways. No direct linear correlation was found between highway runoff pollutant event mean concentrations and AADT. However, through multiple regression analyses, it was shown that AADT has an influence on most highway runoff constituent concentrations, in conjunction with factors associated with watershed characteristics and pollutant build-up and wash off. The other noticeable factors shown to influence the accumulation of pollutants on highways were antecedent dry period, drainage area, maximum rain intensity, and land use. 相似文献
103.
Claus B. Madsen 《Machine Vision and Applications》1997,9(5-6):291-303
The paper presents an analysis of the stability of pose estimation. Stability is defined as sensitivity of the pose parameters
towards noise in image features used for estimating pose. The specific emphasis of the analysis is on determining {how the
stability varies with viewpoint} relative to an object and to understand the relationships between object geometry, viewpoint,
and pose stability. Two pose estimation techniques are investigated. One uses a numerical scheme for finding pose parameters;
the other is based on closed form solutions. Both are “pose from trihedral vertices” techniques, which provide the rotation
part of object pose based on orientations of three edge segments. The analysis is based on generalized sensitivity analysis
propagating the uncertainty in edge segment orientations to the resulting effect on the pose parameters. It is shown that
there is a precomputable, generic relationship between viewpoint and pose stability, and that there is a drastic difference
in stability over the range of viewpoints. This viewpoint variation is shared by the two investigated techniques. Additionally,
the paper offers an explicit way to determine the most robust viewpoints directly for any given vertex model. Experiments
on real images show that the results of the work can be used to compute the variance in pose parameters for any given pose.
For the predicted {instable} viewpoints the variance in pose parameters is on the order of 20 (degrees squared), whereas the
variance for robust viewpoints is on the order of 0.05 (degrees squared), i.e., two orders of magnitude difference. 相似文献
104.
A section is born: Studies in Automated Reasoning 相似文献
105.
106.
SJ Schwarz JR Claus H Wang NG Marriott PP Graham CF Fernandes 《Canadian Metallurgical Quarterly》1997,76(10):1450-1456
The pink color defect in cooked, uncured turkey is a sporadic problem that can result in economic loss and consumer dissatisfaction. Fourteen ligands were tested in ground turkey samples for their ability to reduce pink color development in control samples and in the presence of 150 ppm sodium nitrite or 1.0% nicotinamide (pink color producing agents). The 14 ligands evaluated were: 3-amino pyridine (AP), 4-benzoylpyridine (BP), diethylenetriamine pentaacetic acid (DA), ethylenedinitrilo-tetraacetic acid disodium salt (EA), 2,3 dihydroxybenzoic acid (DB), 3-ethyl pyridine (EP), trans 1,2-diaminocyclohexane-N,N,N',N' tetraacetic acid monohydrate (HA), calcium reduced nonfat dried milk (NM), 2,3 phthalic acid (PA), 3-picoline (PC), pyrrole (PY), pyridazine (PZ), pyridinedicarboxcylic acid (YA), and pyrazinedicarboxcylic acid (ZA). All ligands were incorporated into ground turkey at 0.20 mg/g (meat weight basis) except for NM (30 mg/g). Color was evaluated using a reflectance spectrophotometer to measure pigment changes (nicotinamide hemochrome, nitrosohemochrome) and with a chroma meter to determine CIE L* a* b* values. Reduction in pink color development was apparent with the addition of the ligand alone and in the presence of sodium nitrite and especially nicotinamide. The four most effective ligands tested were DA, EA, HA, and NM. In general, pink color reduction was highest in the ligand only and the ligand plus nicotinamide samples as was observed by CIE a* and nicotinamide hemochrome value reductions. 相似文献
107.
Beyer D. Noack A. Lewerentz C. 《IEEE transactions on pattern analysis and machine intelligence》2005,31(2):137-149
Calculating with graphs and relations has many applications in the analysis of software systems, for example, the detection of design patterns or patterns of problematic design and the computation of design metrics. These applications require an expressive query language, in particular, for the detection of graph patterns, and an efficient evaluation of the queries even for large graphs. In this paper, we introduce RML, a simple language for querying and manipulating relations based on predicate calculus, and CrocoPat, an interpreter for RML programs. RML is general because it enables the manipulation not only of graphs (i.e., binary relations), but of relations of arbitrary arity. CrocoPat executes RML programs efficiently because it internally represents relations as binary decision diagrams, a data structure that is well-known as a compact representation of large relations in computer-aided verification. We evaluate RML by giving example programs for several software analyses and CrocoPat by comparing its performance with calculators for binary relations, a Prolog system, and a relational database management system. 相似文献
108.
Ohne Zusammenfassung 相似文献
109.
Antoine Baylaucq Christian Boned Xavier Canet Claus K. Z berg-Mikkelsen Sergio E. Qui ones-Cisneros Honggang Zhou 《Petroleum Science and Technology》2005,23(2):143-157
Viscosity measurements of well-defined mixtures are useful in order to evaluate existing viscosity models. Recently, an extensive experimental study of the viscosity at pressures up to 140 MPa has been carried out for the binary systems methane + n-decane and methane + toluene, between 293.15 and 373.15 K and for several methane compositions. Although very far from real petroleum fluids, these mixtures are interesting in order to study the potential of extending various models to the simulation of complex fluids with asymmetrical components (light/heavy hydrocarbon). These data (575 data points) have been discussed in the framework of recent representative models (hard sphere scheme, friction theory, and free volume model) and with mixing laws and two empirical models (particularly the LBC model which is commonly used in petroleum engineering, and the self-referencing model). This comparative study shows that the average absolute deviation of the models is between 3.8 and 49.8%, and the maximum deviation is between 11.6 and 78.4%, depending on the considered model. 相似文献
110.
针对组合式同相供电系统同相补偿装置(CCD)的常规控制方法受负载电流检测精度影响严重,且不能良好跟踪高速铁路负载高次谐波电流的缺陷,提出一种选择性谐波电流控制策略。该控制策略仅需要保留CCD的两单相变流器输出电压、电流的检测部分,不需要检测负载电流;并通过矢量比例积分控制器对连接负载的单相变流器输出电流误差中的各次谐波单独跟踪。该设计方法不受负载电流检测精度的影响,对牵引负荷各个频段谐波都具有良好的跟踪性能。利用MATLAB/Simulink搭建组合式同相供电的常规控制模型、改进控制模型和基于改进控制策略的半桥四臂模块化多电平电路模型,对交-直型、交-直-交型、混跑3种负载分别进行控制,仿真验证了改进电流控制方法的正确性以及在实际工程实现中的有效性。 相似文献