Dual FastSLAM: Dual Factorization of the Particle Filter Based Solution of the Simultaneous Localization and Mapping Problem

The process of building a map with a mobile robot is known as the Simultaneous Localization and Mapping (SLAM) problem, and is considered essential for achieving true autonomy. The best existing solutions to the SLAM problem are based on probabilistic techniques, mainly derived from the basic Bayes Filter. A recent approach is the use of Rao-Blackwellized particle filters. The FastSLAM solution factorizes the Bayes SLAM posterior using a particle filter to estimate over the possible paths of the robot and several independent Kalman Filters attached to each particle to estimate the location of landmarks conditioned to the robot path. Although there are several successful implementations of this idea, there is a lack of applications to indoor environments where the most common feature is the line segment corresponding to straight walls. This paper presents a novel factorization, which is the dual of the existing FastSLAM one, that decouples the SLAM into a map estimation and a localization problem, using a particle filter to estimate over maps and a Kalman Filter attached to each particle to estimate the robot pose conditioned to the given map. We have implemented and tested this approach, analyzing and comparing our solution with the FastSLAM one, and successfully building feature based maps of indoor environments.     

Characterisation of gold kiwifruit pectin isolated by enzymatic treatment

Pectin was extracted from gold kiwifruit by four commercial enzyme preparations (Celluclast 1.5 L, Cytolase CL, Cellulyve TR 400 and NS33048). The chosen enzymes were used either in single or in combination, with and without protease addition. The recovered pectin was characterised and compared for the yield, total nonstarch polysaccharide and neutral sugar composition, protein and ash, pectin, molecular weight distribution and the viscosity. Results indicated that enzyme‐extracted gold kiwifruit pectin was rich in galacturonic acid. Purified pectin yield, and their physicochemical composition and rheological property (viscosity), was significantly affected by the type of enzyme used. The pectin extracted by Celluclast 1.5 L demonstrated to be the most viscous and recorded the highest in molecular weight (M_w) (1.65 × 10⁶ g mol^–1) compared with the other extracts. The extract M_w and their distribution were discussed and related to their viscosity behaviour.     

Recent trends in the lipid‐based nanoencapsulation of antioxidants and their role in foods

Antioxidants may be utilised for two main purposes, to protect the sensory and nutritive quality of the food and/or to protect the body against chronic and age‐related diseases. Generally, antioxidants are subject to process degradation and, when given to the body in their free form, cannot pass cell membranes and are rapidly cleared from the general circulation. Because of their unique properties, lipid‐based nanoencapsulation systems enhance the performance of antioxidants by improving their solubility and bioavailability, in vitro and in vivo stability, and preventing their unwanted interactions with other food components. This paper reviews nanoliposomes, archaeosomes and nanocochleates with respect to their potential applications as antioxidant carriers in foods. Copyright © 2006 Society of Chemical Industry     

Local map fusion for real‐time indoor simultaneous localization and mapping

Among the solutions to the simultaneous localization and mapping (SLAM) problem with probabilistic techniques, the extended Kalman filter (EKF) is a very common approach. There are several approaches to deal with its computational cost, usually based on an adequate selection of features to be updated in real time, while the whole map update is delayed or processed in a background task, allowing one to map larger environments or to carry out multirobot experiments. Although these solutions are theoretically sound, there is a great lack of real experiments in large indoor environments due to several previously unknown problems derived from the geometric model of the map features and the inconsistency of the SLAM‐EKF algorithm. For the first time, these problems are described and solved, and the implementation of the algorithms and solutions presented in this paper achieve excellent results in experiments in different real large indoor environments. © 2006 Wiley Periodicals, Inc.     

Gel and Pasting Behaviour of Fenugreek‐Wheat Starch and Fenugreek – Wheat Flour Combinations

The influence of fenugreek material on starch and flour rheological characteristics was determined. Ground fenugreek grain material, and a purified fenugreek extract (Fenulife®) were used as replacement or as addition to flour or starch. Evaluation of the pasting properties of starch and flour fenugreek mixtures illustrated that fenugreek addition increased the peak and final viscosity of the mixtures in relation to the level of fenugreek addition used. The ground fenugreek seeds yielded a lower response than the purified Fenulife® sample, due to the presence of protein, starch and other polysaccharide material in the ground flour. Rheology of the pastes showed that the addition of fenugreek material (especially Fenulife®) increased the viscoelastic nature of the material. Textural analysis of the cooled gels illustrated that the inclusion of fenugreek into flour mixes generally raised the hardness of the gels, although the gels became softer with higher levels of fenugreek material used. The inclusion of fenugreek into starch gels showed similar patterns of pasting and textural properties, with a general decrease in texture related to the level of fenugreek included.     

The Relationship Between Wheat Flour and Starch Pasting Properties and Starch Hydrolysis: Effect of Non‐starch Polysaccharides in a Starch Gel System

Non‐starch polysaccharides (NSPs) and celite (used as inert filler) were incorporated into wheat flour and wheat starch paste preparations at levels of 1, 2.5, and 5% in both addition and replacement modes. Pasting properties of gums were compared using a Rapid Visco Analyser. Use of guar gum and locust bean gum elevated the peak and final viscosities of the resulting pastes (when used in either addition or replacement modes), whereas arabic gum significantly reduced the peak and final viscosity properties of the pastes. Samples which comprised wheat starch yielded higher peak and final viscosity characteristics compared to wheat flour containing samples, however higher breakdown and setback values were observed for samples using wheat flour as a base compared to wheat starch. The firmness of the gels (as determined using a texture analyser) increased with the use of wheat starch compared to wheat flour. Little significant difference was observed between NSP used and mode of application (replacement or addition). In vitro starch degradation was conducted on the wheat flour gels. Guar gum and locust bean gum reduced the amount of starch degradation in these gels, whereas arabic gum and celite increased the amount of starch hydrolysis (or were similar to the control). The rate of starch hydrolysis appears to be related to the viscosity altering behaviour of the NSPs in a starch‐rich system. The results indicate that selection of NSPs is important as gum arabic has the potential to increase starch hydrolysis compared to the control.     

Effect of blending two treated waters on the organoleptic profile of Barcelona's supply.

Barcelona's drinking water has two distinct origins: the Ter and Llobregat rivers supply the city in a ratio of 35/65. The organoleptic quality of the two waters is very different. Treated water from the Llobregat sometimes has organoleptic problems, whereas the quality of treated water from the Ter is much better. The aim of this paper is to study the effects of blending the two types of water and to determine the best blend of the Ter and Llobregat treated waters in terms of flavour and odour, using the A/not A test and the Flavour Profile Analysis. The optimum blend of Ter and Llobregat water is the blend that contains the highest percentage of Llobregat water without any appreciable loss of the characteristics of Ter water.     

A review of taste and odour events in Barcelona's drinking water area (1990-2004).

The main, relevant, solved problems associated with taste and odour incidents in Barcelona's drinking water area in the last 14 years are reviewed. Events produced by creosote, dioxanes and dioxolanes, dicylopentadiene, and diacetyl, among the anthropogenic compounds; geosmin, MIB and iodinated trihalomethanes and chlorobromoanisoles as examples of compounds of natural origin are exemplified. The determination of the odour threshold concentrations of selected odorous compounds is also shown as a tool to gain a better knowledge of future taste and odour events.