Improving "bag-of-keypoints" image categorisation: Generative Models and PDF-Kernels

In this paper we propose two distinct enhancements to the basic ''bag-of-keypoints" image categorisation scheme proposed in [4]. In this approach images are represented as a variable sized set of local image features (keypoints). Thus, we require machine learning tools which can operate on sets of vectors. In [4] this is achieved by representing the set as a histogram over bins found by k-means. We show how this approach can be improved and generalised using Gaussian Mixture Models (GMMs). Alternatively, the set of keypoints can be represented directly as a probability density function, over which a kernel can be de ned. This approach is shown to give state of the art categorisation performance

Kinetics of alfalfa nitrogen and cell wall disappearance from ruminally-incubated dacron bags

Kinetics of the disappearance of alfalfa N and cell wall (CW) from ruminally-incubated dacron bags were determined and compared in two separate studies. Alfalfa harvested at three maturity stages (early bud, first bloom, and seed pod) and treated with either 10% NaOH or heated at 150 C for 4 h was utilized in trial 1. In trial 2, alfalfa leaves, stems, and a 50:50 leaf/stem mixture were ruminally-incubated in steers fed either hay or an 85% concentrate diet. Parameters determined were rates of disappearance (k) of the potentially digestible (RD) N and CW fractions in bag residues, proportions of RDN and RDCW, and estimates of the discrete lag period prior to initiation of digestion;Rate constants (-k/h) generally averaged .16 for CW and .36 for N in first bloom, whole plant alfalfa incubated in hay-fed animals. Rates tended to be inversely related to advancing maturity and stem content; declines of a similar degree were noted in both CW and N estimates. RDCW averaged approximately 50% of the total CW in first bloom and mixed forages. Approximately 40-60% of initial plant N was lost when the bags were washed after incubation; RDN, consequently, ranged from 34% (seed pod stage forage) to 46% (leaves). Lag times for N and CW in untreated forage were variable and generally less than 1.5 h. Heat treatment produced marked declines in disappearance rates; k values ranged from -.04 to -.06/h for both N and CW. RDN and RDCW were also reduced whereas lag times were increased two- to three-fold. Alkali treatment caused little change in CW rate constants but reduced by nearly half those derived for N in untreated forages. RDN and RDCW were increased by alkali treatment, particularly in later maturity forages; lag times also tended to be increased. Incubation of forage substrates in animals fed high-grain diets caused declines of 40-60% in N and CW rate constants. Diet, however, had little effect on RD fractions or lag times;Through regressions of N and CW rate constants on the fractional contribution by stems to each of the substrates examined in the second trial, the existence of a quantitative relationship between N and CW disappearance was established. Slopes for N and CW regression lines, whether obtained with k values derived from incubations in hay- or grain-fed animals, were identical. Effects on such an interaction on the efficiency of animal utilization of forage N are discussed

Two view learning: SVM-2K, theory and practice

Kernel methods make it relatively easy to define complex highdimensional feature spaces. This raises the question of how we can identify the relevant subspaces for a particular learning task. When two views of the same phenomenon are available kernel Canonical Correlation Analysis (KCCA) has been shown to be an effective preprocessing step that can improve the performance of classification algorithms such as the Support Vector Machine (SVM). This paper takes this observation to its logical conclusion and proposes a method that combines this two stage learning (KCCA followed by SVM) into a single optimisation termed SVM-2K. We present both experimental and theoretical analysis of the approach showing encouraging results and insights

Lead Isotope Data for Gold-Bearing Veins and Their Host Metasedimentary Rocks of the Goldenville Formation, Eastern Nova Scotia

Lead isotope analyses have been determined for galenas which occur in small quantities in quartz veins in the Goldenville Formation of the Meguma Terrane, and also for five whole rock samples from this formation- The ten least radiogenic galenas are homogeneous in isotopic composition, and they plot close to the average terrestrial growth curve of Stacey and Kramers and the "orogene" curve of Doe and Zartman. The mean model ages are 550 Ma (Stacey and Kramers) and 600 Ma (Doe and Zartman), which are in approximate agreement with the Cambro-Ordovician age of deposition of the sediments. The close position of the galena compositions to these average growth curves suggests that these compositions were established by mixing processes as envisaged in the Doe and Zartman "plumbotectonics" model. The isotopic analyses of the whole rocks indicate that small amounts of radiogenic lead are present in non-mineralized sections of the sedimentary sequence- Three galenas from veins in rocks metamorphosed to biotite and staurolite-andalusite grades, and from late veins (post-dating deformation, metamorphism and plutonism) are significantly more radiogenic than the majority of the samples. We interpret the isotopic characteristics of these galenas to be the result of extraction of lead from Meguma metasediments or of additions of radiogenic lead to less radiogenic lead during remobllization. Other interpretations consistent with the isotopic data are possible. RÉSUMÉ Des analyses aux isotopes de plomb ont été déterminé pour les galènes qui se trouvent en petite quantitié's dans les veines de quartz de la formation Goldenville du terrane Meguma, et aussi pour cinq échantillons de roches entieres de cette formation. Les dix galènes les moins radiogèniques sont homogènes en composition isotopique, et elles ont une trace proche de la courbe de croissauce terreste moyenne de Stacey et Kramers, et de la courbe "orogène" de Doe et Zartman. Le âges moyens des modules sont de 550 Ma (Stacey et Kramers) et de 600 Ma (Doe et Zartman), ce qui s'accorde approximativement avec l'âge Cambro-Ordovicien du dépôt des sédiments. La position proche des compositions de la galène avec ces courbes moyennes de croissance, indique que ces compositions ont été établies par un processus de mélanges, comme le propose le modèle "Piumbotectonique" de Doe et Zartman. Les analyses isotopiques de roche entiere indiquent que de petites quantitié's de plomb radiogenique sont présences dans les sections non-minéralisees de la séquence sédimentaire. Trois galènes, provenant de veines de roches métamorphosée au dégris de biotite et de staurolite-anda lusite, et de veines avancées (post-datant la déformation, le métamorphisine et le plutonisme) sont d'une maniere significative plus radiogèniques que la majoritié des échantillons. Nous interprètons les caractéristiques isotopiques de ces galènes comme le résultat de l'extraction de plomb des méta-sédiments Meguma, ou a L’addition de plomb radiogènique au plomb moins radiogènique durant la remobilisation. D'autres Interprètations en accord avec les donnés isotopiques sont possible. [Traduit par le journal

Addressing the social determinants of health: A case study from the Mitanin (Community Health Worker) programme in India

The Mitanin Programme, a government community health worker (CHW) programme, was started in Chhattisgarh State of India in 2002. The CHWs (Mitanins) have consistently adopted roles that go beyond health programme- specific interventions to embrace community mobilization and action on local priorities. The aim of this research was to document how and why the Mitanins have been able to act on the social determinants of health, describing the catalysts and processes involved and the enabling programmatic and organiza- tional factors. A qualitative comparative case study of successful action by Mitanin was conducted in two ‘blocks’, purposefully selected as positive exemplars in two districts of Chhattisgarh. One case focused on malnutrition and the other on gender-based violence. Data collection involved 17 in-depth interviews and 10 group interviews with the full range of stakeholders in both blocks, including community members and programme team. Thematic analysis was done using a broad conceptual framework that was further refined. Action on social determinants involved raising awareness on rights, mobilizing women’s collectives, revitalizing local political structures and social action targeting both the community and government service providers. Through these processes, the Mitanins developed identities as agents of change and advocates for the community, both with respect to local cultural and gender norms and in ensuring accountability of service providers. The factors underpinning successful action on social determinants were identified as the significance of the original intent and vision of the programme, and how this was carried through into all aspects of programme design, the role of the Mitanins and their identification with village women, ongoing training and support, and the relative autonomy of the programme. Although the results are not narrowly generalizable and do not necessarily represent the situation of the Mitanin Programme as a whole, the explanatory framework may provide general lessons for programmes in similar contexts.Web of Scienc

Inducer dynamics full-flow, full-admission hydraulic turbine drive Interim report for tasks 1, 2, and 3

Hydrodynamical and mechanical design layout for two-speed hydraulic turbine inducer, computer simulation of pumping system and test facility performance, and study of demonstration uni