Thumbs up? Sentiment Classification using Machine Learning Techniques

We consider the problem of classifying documents not by topic, but by overall sentiment, e.g., determining whether a review is positive or negative. Using movie reviews as data, we find that standard machine learning techniques definitively outperform human-produced baselines. However, the three machine learning methods we employed (Naive Bayes, maximum entropy classification, and support vector machines) do not perform as well on sentiment classification as on traditional topic-based categorization. We conclude by examining factors that make the sentiment classification problem more challenging.Comment: To appear in EMNLP-200

Women's Access To Training In The Rubber Smallholder Sector In The District Of Hulu Langat, Selangor Darul Ehsan, Malaysia

The focus of the study was on women I s access to training which is operationally defined as getting to hear and participating in training in the form of short courses , workshops , seminars , demonstrations and study visits. The specific objectives of the study were : ( 1 ) to identify whether women in the rubber smallholder sector had access to training ; ( 2 ) to identify reasons related to women's access and non-access to training ; ( 3 ) to discover their understanding of training;( 4 )to discover the experiences during training of those women who had access; and ( 5 ) to discover their benefits and losses from training

Dégradation aérobie des biosolides municipaux et récupération de biocatalyseurs pour le traitement des eaux usées

Le volume élevé de biosolides municipaux et industriels (BS) produits dans le monde entier est une source de préoccupation majeure pour les écologistes. Actuellement, la production mondiale de BS est estimée à environ 100 à 125 millions de tonnes par an et devrait augmenter continuellement. Au Canada, 6,6 millions de tonnes de BS stabilisés secs sont produites chaque année par plus de 3 500 stations d’épuration des eaux usées (STEP). La gestion et l’élimination des BS sont très préoccupantes pour de nombreuses municipalités, car cela peut représenter plus de la moitié du coût total du traitement des eaux usées. La valorisation des BS pour la production de biogaz présente un grand avantage. En effet, la digestion anaérobie des BS peut être utilisée pour produire du biogaz comme combustible si celui-ci est correctement collecté et purifié. Outre cet avantage, les BS représentent une menace environnementale à travers la production de gaz à effet de serre (GES), et la production de lixiviat contenant de nombreux contaminants organiques (incluant des contaminants organiques à l’état de traces (TrOCs), tels que les composés pharmaceutiques actifs (PhACs) et pesticides). Ainsi, à partir des sites d'enfouissement et de l'amendement des sols avec les BS municipales, ces contaminants peuvent se retrouver dans les eaux souterraines. Pour remédier à cela, le Québec a mis en place des politiques strictes en matière d’élimination des BS. On compte parmi les mesures prises l’interdiction du déversement des BS dans les décharges et établit une taxe verte qui est prélevée en fonction de l’inflation pour chaque tonne de BS incinérée ou mise en décharge au Québec. Cependant, avec l’aide de technologies de bioprocédés avancées, ces BS peuvent être traités et utilisés simultanément comme matière première pour la production de produits de grande valeur ou de précurseurs de produits de grande valeur. Ce travail de recherche fournit une évaluation des principales méthodes d’élimination (réduction du volume et des contaminants) et passe en revue l’état des processus biotechnologiques, en particulier pour la digestion aérobie pour la production d’enzymes hydrolytiques et lignolytiques à partir des BS. En premier lieu, l’impact des microorganismes endogènes a été étudié avec ou sans co-traitement. En ce sens, divers traitements comprenant l’utilisation de microorganismes indigènes présents dans les BS, l’effet combiné d’un prétraitement enzymatique, la biostimulation par l’ajout d’une source externe de carbone et l’effet synergique de la biostimulation et du prétraitement enzymatique ont été étudiés pendant 28 jours. En raison de diverses stratégies de traitement, une réduction totale des solides en suspension de 12% à 23%, une élimination des PhACs de 44% à 62% et une élimination des pesticides d’environ 10% à 54% ont été observées. Aussi, pour améliorer l’élimination des solides en suspension des PhACs et pesticides, l’effet de quatre stratégies de prétraitement différentes (ultrasonication, congélation-décongélation, addition enzymatique et traitement alcalin), suivis d’une bioaugmentation avec la souche de bactérie Bacillus subtilis a été étudiée. Après 28 jours de traitement, la bioaugmentation a amélioré l’élimination totale des solides en suspension par 8 à 54% et une l’élimination des PhACs par 21 à 80% et une l’élimination des pesticides par 22 à 76%. La production d‘un cocktail d’enzymes extracellulaires (ex. : laccase, peroxydase, glucose oxydase, lipase, phosphatase, estérase…etc.) à la suite de la bioaugmentation des BS avec B. subtilis a été observée. Ces enzymes peuvent être impliquées dans l’élimination des contaminants présents dans les BS ainsi que dans la réduction des solides observée. Cette étude est une approche bio-intégrée, où les enzymes produites lors de la digestion aérobie des BS ont été évaluées pour l’élimination des contaminants organiques présents dans les BS issus du traitement des eaux usées municipales. Pour souligner cela, la bioaugmentation des BS avec la souche de champignon Aspergillus niger a été évaluée dans le but de produire une enzyme d’intérêt telle que la glucose oxydase (GOD). La GOD sécrétée par A. niger, a été utilisée pour le processus d’oxydation avancé basé sur le bio-Fenton pour la dégradation de 15 PhACs d’intérêt dans l’eau. En somme, l’utilisation des BS comme substrat par les microorganismes étudiés a permis d’une part de diminuer les contaminants organiques et, d’autre part, de réduire le volume des BS.Abstract : The high volume of municipal and industrial biosolids (BS) produced all over the world is a cause of major concern to the environmentalists these days. Currently, the worldwide production of BS is estimated to be around 100-125 million tonnes per year and is expected to increase continuously. According to Canadian context reported on, 6.6 million tonnes of dry stabilized BS are generated yearly by more than 3500 wastewater treatment plants (WWTPs). Management of BS is primarily handled as a technical matter. The disposal of BS is of great concern for many WWT facilities because it accounts for over half of the total cost of wastewater treatment. BS disposal in landfill sites leads to a great advantage of biogas generation by anaerobic digestion which can be used as a fuel if the biogas is properly collected. Apart from adding advantages, it poses environmental threat such as trace organic contaminants (TrOCs), green house gases (GHGs) production, potential contaminant leachate into the ground water system at the landfill site as well as soil amendment of municipal BS . Stringent laws in BS disposal are followed in Quebec which focuses on restraining from the dumping of BS in landfills and green tax is levied based on the inflation for each ton of biosolid that is incinerated or landfilled in Quebec. However, with the help of advance bioprocess technologies these biosolids can be treated and simultaneously used as a raw material for the production of high value products or high value product precursors. This current research work delivers an assessment of the leading disposal methods (volume and contaminant reduction) and reviews the state of biotechnological processes, particular to aerobic digestion for the production of hydrolytic and lignolytic enzymes from BS. During aerobic digestion, various pretreatments including utilization of indigenous microbes present in BS, the effect of an enzymatic pretreatment, biostimulation by the addition of an external carbon source and the synergic effect of biostimulation and enzymatic pretreatment were studied for 28 days. As a result of various treatment strategies, the total suspended solids reduction of 12-23% ,total PhACs removal of 44-62% and total pesticides removal around 10- 54% were observed. Further, to enhance the total suspended solids, total PhACs and total pesticides removal, effect of four different pre-treatment strategies (ultrasonication, freezethawing, enzymatic and alkaline addition) subsequent bioaugmentation with Bacillus subtilis for IV 28 days were studied. Impact of bioaugmentation improved the total suspended solids removal by 8-54%, total PhACs removal by 21-80% and total pesticides removal by 22-76%. The production of enzymatic cocktail by bioaugmented along with indigenous microorganisms, which contain high laccase, peroxidase, glucose oxidase, lipase, phosphatase, esterase activities and other activities related to elimination of contaminants present in the BS. This study is biointegrated approach, where the enzymes producing during aerobic digestion of BS is evaluated to reduce the contaminants present in water or wastewater. To emphasize that, bioaugmentation of Aspergillus niger to BS to produce glucose oxidase (GOD), which was utilized for bio-Fenton based advanced oxidation process for the partial removal of 15 pharmaceutically active compounds in water. Therefore, the use of BS residuals as a substrate can decrease the contaminants on the one hand and, on the other hand, it can reduce the volume of BS

PREPARATION OF MAGNESIUM HYDROXIDE NANOPARTICLES FROM BITTERN

Magnesium hydroxide is an important material with high decomposition temperature. It is the important precursor for magnesium oxide. In the present study, nanoparticles of magnesium hydroxide were prepared from bittern. Bittern is the waste liquid formed during the production of salt. Since it is rich in magnesium, magnesium hydroxide nanoparticles can be prepared. The nanoparticles were characterized by SEM, EDS and TG-DTA

Thickness dependence of the properties of epitaxial MgB2 thin films grown by hybrid physical-chemical vapor deposition

We have studied the effect of deposition rate and layer thickness on the properties of epitaxial MgB2 thin films grown by hybrid physical-chemical vapor deposition on 4H-SiC substrates. The MgB2 film deposition rate depends linearly on the concentration of B2H6 in the inlet gas mixture. We found that the superconducting and normal-state properties of the MgB2 films are determined by the film thickness, not by the deposition rate. When the film thickness was increased, the transition temperature, Tc, increased and the residual resistivity, rho0, decreased. Above about 300 nm, a Tc of 41.8 K, a rho0 of 0.28 mikroOhm.cm, and a residual resistance ratio RRR of over 30 were obtained. These values represent the best MgB2 properties reported thus far.Comment: 10 pages, 4 figure

Developing regional capacity in operations research and economic evaluation in South Asia

This project contributed significantly to the capacity-building of regional professionals in planning, implementing, and monitoring of reproductive health programs in South Asia. During 2001–05, professionals from 17 countries received training in various aspects of reproductive health in nine workshops, including operations research, economic evaluation, qualitative research methods, proposal writing, and process documentation and enhancing the utilization of research findings in reproductive health programs. Forty-three percent of workshop participants were program managers from government health programs and nongovernmental organizations. Success in leveraging resources from other collaborating agencies and other donors helped the project to organize more workshops than originally planned and train more professionals than expected. A survey of the workshop participants four to 38 months after training revealed that 70 percent of respondents were using their newly acquired skills in programmatic improvement, program development, and conducting operations research

Silver segregation to \theta' (Al2Cu)-Al interfaces in Al-Cu-Ag alloys

\theta' (Al2Cu) precipitates in Al-Cu-Ag alloys were examined using high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). The precipitates nucleated on dislocation loops on which assemblies of {\gamma}' (AlAg2) precipitates were present. These dislocation loops were enriched in silver prior to \theta' precipitation. Coherent, planar interfaces between the aluminium matrix and \theta' precipitates were decorated by a layer of silver of two atomic layers in thickness. It is proposed that this layer lowers the chemical component of the Al-\theta' interfacial energy. The lateral growth of the \theta' precipitates was accompanied by the extension of this silver bi-layer, resulting in the loss of silver from neighbouring \gamma' precipitates and contributing to the deterioration of the \gamma' precipitate assemblies.Comment: Pre-print. 12 pages, 7 figure

Bootstrapped-ensemble-based Sensitivity Analysis of a trace thermal-hydraulic model based on a limited number of PWR large break loca simulations

[EN] The safety verification of nuclear systems can be done by analyzing the outputs of Best-Estimate Thermal-Hydraulic (BE-TH) codes, which allow predicting the system response under safe and accidental conditions with greater realism as compared to conservative TH codes. In this case, it is necessary to quantify and control the uncertainties in the analysis, which affect the estimated safety margins. This can be achieved by Sensitivity Analysis (SA) and Uncertainty Analysis (UA) techniques tailored to handle the large computational costs of TH codes. This work presents an Ensemble-Based Sensitivity Analysis (EBSA) based on Finite Mixture Model (FMM) as an effective solution to keep low the code runs and handle the uncertainty in the SA methods. The approach proposed is challenged against a situation of a very low number of code runs: the Bootstrap method is, then, used in support. Three different strategies based on EBSA and Bootstrap are set forth (i.e., bottom-up, all-out and filter strategies). An application is provided with respect to a Large Break Loss of Coolant Accident (LBLOCA) simulated by a TRACE model of the Zion 1 Nuclear Power Plant (NPP).Di Maio, F.; Bandini, A.; Zio, E.; Carlos Alberola, S.; Sanchez Saez, F.; Martorell Alsina, SS. (2016). Bootstrapped-ensemble-based Sensitivity Analysis of a trace thermal-hydraulic model based on a limited number of PWR large break loca simulations. Reliability Engineering & System Safety. 153:122-134. doi:10.1016/j.ress.2016.04.013S12213415

A phase-field model for phase transformations in glass-forming alloys

A phase-field model is proposed for phase transformations in glass-forming alloys. The glass transition is introduced as a structural relaxation, and the competition between the glass and crystalline phases is investigated. The simulations are performed for Cu-Zr alloys, employing thermodynamic and kinetic parameters derived from reported thermodynamic modeling and molecular dynamics simulation results,[1–3] respectively. Four distinct phase fields are treated with a multi-phase-field approach, representing the liquid/glass, Cu10Zr7, CuZr, and CuZr2 phases. In addition, a continuum-field method is applied to the liquid to accommodate the liquid–glass transformation. The combined phase-field approach is used to investigate the glass formation tendency, and critical cooling rates are estimated and compared with the reported experimental values