925 resultados para Study of methods and timings
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This paper provides an updated review on fast pyrolysis of biomass for production of a liquid usually referred to as bio-oil. The technology of fast pyrolysis is described including the major reaction systems. The primary liquid product is characterised by reference to the many properties that impact on its use. These properties have caused increasingly extensive research to be undertaken to address properties that need modification and this area is reviewed in terms of physical, catalytic and chemical upgrading. Of particular note is the increasing diversity of methods and catalysts and particularly the complexity and sophistication of multi-functional catalyst systems. It is also important to see more companies involved in this technology area and increased take-up of evolving upgrading processes. © 2011 Elsevier Ltd.
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This article presents the findings of a central Florida study of lodging and restaurant managers as well as entry-level workers who were graduates of hospitality management programs. It provides a theoretical construct as a basis of the methodology employed. The article then reports the findings of perceptions of desired knowledge, skills and abilities, and attitudes associated with entry-level employees. It further compares desired levels of preparation for entry-level positions in the industry as reported by respondents of both groups. Finally, the authors present conclusions and implications for central Florida practitioners and educators.
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Understanding the preservation and deposition history of organic molecules is crucial for the understanding of paleoenvironmental information contained in their abundance ratios such as Uk'37 and TEX86 used as proxies for sea surface temperature (SST). Based on their relatively high refractivity, alkenones and glycerol dialkyl glycerol tetraethers (GDGTs) can survive postdepositional processes like lateral transport, potentially causing inferred SSTs to be misleading. Likewise, selective preservation of alkenones and GDGTs may cause biases of the SST proxies themselves and can lead to decoupling of both proxy records. Here we report compound-specific radiocarbon data of marine biomarkers including alkenones, GDGTs, and low molecular weight (LMW) n-fatty acids from Black Sea sediments deposited under different redox regimes to evaluate the potentially differential preservation of both biomarker classes and its effect on the SST indices Uk'37 and TEX86 . The decadal D14C values of alkenones, GDGTs, and LMW n-fatty acids indicate similar preservation under oxic, suboxic, and anoxic redox regimes and no contribution of pre-aged compounds, e.g., by lateral supply. Moreover, similar 14C concentrations of crenarchaeol, alkenones, and LMW n-fatty acids imply that the thaumarchaeotal GDGTs preserved in these sediments are produced in the euphotic zone rather than in subsurface/thermocline waters. However, we observe biomarker-based SSTs that strongly deviate (deltaSST up to 8.4 °C) from in situ measured mean annual SSTs in the Black Sea. This is not due to redox-dependent differential biomarker preservation as implied by their D14C values and spatial SST pattern. Since contributions from different sources can largely be excluded, the deviation of the Uk'37 and TEX86 proxy-derived SSTs from in situ SSTs requires further study of phylogenetic and other yet unknown environmental controls on alkenone and GDGT lipid distributions in the Black Sea.
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The Mermaid Series (1887-1909) edited by Havelock Ellis was a major watershed in appreciation of Elizabethan and Jacobean drama. Before it appeared plays were available to general readers in scattered anthologies, large expensive collected editions or in expurgated selections which included only the more lyrical speeches and memorable scenes. Criticism of the drama followed suit; the majority of critics concentrated on the sections which appealed to the romantic and sentimental tastes of nineteenthcentury readers. The two men who conceived the Mermaid Series, John Addington Symonds and Havelock Ellis, approached the drama differently from their contemporaries; Symonds studied a play as a whole work of art and Ellis concentrated on its view of life. Both were unsatisfied with the "select beauties", fragmented approach and wanted readers to have the best plays in their entirety easily available in handy, inexpensive editions. Symonds's awareness of the drama as theatre was combined with a historical perspective allowing him to judge the drama in relation to its own time. He made a lasting but hitherto underestimated contribution to study of Beaumont and Fletcher, Dekker, Marlowe, and Ford. Ellis's work on the drama is overshadowed today by his studies of sex but his concentration on ideas and appreciation of unconventional behaviour enabled him to formulate new views on Ford, Middleton and Chapman. The two other major editors to work on the series, A. C. Swinburne and Arthur Symons had more conventional nineteenth-century approaches. Both were impressionistic critics who were most attracted to the l~nguage of the drama. Swinburne, however, occasionally transcended his fragmented approach and offered significant interpretations of Tourneur, Massinger; 'The .Changeling, Heywood. Symons's range was more limited but his form of impressionism was valuable for its concentration on the aesthetic experience at the heart of a work of art. His most important contributions were the study of Middleton and Massinger. Besides these four major critics numerous lesser writers worked on the series. Their editorial work was valuable and some, notably Ernest Rhys, c. H. Herford and Thomas Dickinson offered criticism of enduring importance. In my first chapter I consider the general availability of texts of the Elizabethan and Jacobean drama in the nineteenth century, the general attitudes towards the drama, and the critical approaches of each of the editors. The subsequent chapters are organized around the volumes of the series. I consider the climate of opinion in which each appeared, assess its critical and editorial contribution and evaluate the work of the other Mermaid editors on the dramatist included in the volume. My study shows that the concept of the Mermaid Series and the work of its editors helped to revolutionize study of the Elizabethan and Jacobean dramatists by providing good texts and by pointing the way to our present view of the plays as whole works of art.
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Este trabalho teve o intuito de criar uma linha de montagem universal através da qual será dada formação aos atuais operadores e a novos que possam vir a pertencer ao departamento de montagem na empresa Grohe Portugal. Para tal era necessário saber realizar um estudo de métodos e um estudo de tempos sobre os vários processos existentes no departamento de montagem. Com esse intuito foi elaborada uma pesquisa sobre as referidas temáticas, onde ficou evidente a sua importância e a sua imprescindibilidade. Inicialmente houve também um acompanhamento das montagens dos produtos nas várias linhas, de forma a adquirir conhecimento sobre as características dos processos de montagem existentes no departamento. Os pontos mais importantes durante o estudo de métodos e tempos realizado foram a definição de toda a estrutura do processo, das ferramentas e materiais a utilizar, não esquecendo a relação entre o operador e as suas ferramentas e a medição de tempos de todas as tarefas necessárias para cada processo de montagem. A linha de montagem, cujo projeto se desenvolveu, é composta por três bancadas e consiste num conjunto de postos de trabalho onde são executadas as operações através de máquinas, do trabalho humano, ou da sua conjugação, dispostos numa determinada sequência, sendo alguns deles amovíveis. Para a realização e conclusão deste projeto foram superadas diversas etapas, sendo que as mais relevantes foram: a análise dos processos de montagem; estudo de tempos de todas as famílias de produtos a serem implementados na linha de formação; - Definição da estrutura da linha de montagem; - Definição das rampas e dos tubos de abastecimento da linha; - Desenho da linha de montagem em 3D no software SolidWorks. Paralelamente foram também desenvolvidos estudos de tempos sobre alguns produtos com o intuito de serem implementadas melhorias, ou apenas para o controlo de tempos necessários para a realização das operações Por último, foi também elaborada uma recolha de ferramentas existentes no departamento de montagem para serem elaborados manuais de instruções das ferramentas fabricadas internamente, com o objetivo de obter a certificação OSHAS 180001 e de criar documentos com a listagem de materiais necessários para cada produto.
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Hoje em dia, e com os avanços tecnológicos a surgirem de forma constante, existem novas áreas que têm de ser consideradas com um foco importante por parte de todas as organizações, sendo uma delas a robótica industrial. Motivada em aumentar o seu output, as condições de trabalho para os seus colaboradores, bem como todas as condições de organização da logística interna, a Grohe Portugal, mais especificamente o departamento da montagem, achou relevante fazer um estudo de métodos e tempos, calculando os ganhos potenciais de aumento de output com introdução de robótica nas linhas dos cartuchos. Os objetivos principais seriam então, fazer uma restruturação de todo o layout dessas linhas, tendo como foco automatizar alguma(s) operação(ões), conseguindo assim uma melhoria significativa do output dessas linhas com o menor payback possível. Posto isto, esta dissertação pretende apresentar o trabalho desenvolvido junto da Grohe Portugal, que teve como objetivo fazer os estudos e a automatização de linhas de montagem de cartuchos, bem como melhorar algumas linhas de montagem tendo em conta fatores ergonómicos. Relativamente à automatização da linha dos cartuchos, foi importante estudar todos os seguintes aspetos: utilização de unidades robóticas; ergonomia; ganhos de produtividade; automatizar ou semi-automatizar operações; simplificar processos de montagem; simplificar setups; solicitar orçamentos; elaborar caderno de encargos. Para a realização deste projeto, o trabalho desenvolvido foi decomposto em várias etapas, entre as quais se destacam: análise e estudo dos métodos e sequências de montagem; levantamento de todos os componentes e operações de montagem até à obtenção do cartucho final; estudo de tempos de todas essas operações de montagem; caraterização de um novo layout para as linhas com a introdução de unidades robóticas, tanto quanto possível, mais adequadas; elaboração de caderno de encargos para ser enviado a empresas, para estas poderem apresentar uma orçamentação, bem como indicar as unidades robóticas mais adequadas para as tarefas pretendidas; automatização da linha dos cartuchos. Relativamente ao projeto de novas linhas de montagem tendo em conta fatores ergonómicos, de forma a melhorar os sistemas de abastecimento e as condições de trabalho por parte dos operadores, foram postos em prática diferentes passos, nomeadamente: identificação de todos os processos de montagem realizados pelos operadores na linha a melhorar; estudo e definição da disposição dos componentes na nova linha, bem como a sua forma de abastecimento; projeto da nova linha de montagem em 3D com recurso ao software SolidWorks; realização prática da linha, acompanhando e ajudando a equipa da ferramentaria. O balanço final do trabalho foi bastante positivo, tanto na automatização das linhas de montagem dos cartuchos, em que todo o seu estudo foi alcançado com sucesso, como no melhoramento ergonómico das linhas de montagem, tendo-se alcançado melhorias em alguns índices de qualidade, tempos de abastecimento, organização das linhas, e nas condições de iluminação, resultando essas melhorias numa avaliação positiva por parte dos colaboradores que nelas trabalham todos os dias.
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The ongoing growth of the World Wide Web, catalyzed by the increasing possibility of ubiquitous access via a variety of devices, continues to strengthen its role as our prevalent information and commmunication medium. However, although tools like search engines facilitate retrieval, the task of finally making sense of Web content is still often left to human interpretation. The vision of supporting both humans and machines in such knowledge-based activities led to the development of different systems which allow to structure Web resources by metadata annotations. Interestingly, two major approaches which gained a considerable amount of attention are addressing the problem from nearly opposite directions: On the one hand, the idea of the Semantic Web suggests to formalize the knowledge within a particular domain by means of the "top-down" approach of defining ontologies. On the other hand, Social Annotation Systems as part of the so-called Web 2.0 movement implement a "bottom-up" style of categorization using arbitrary keywords. Experience as well as research in the characteristics of both systems has shown that their strengths and weaknesses seem to be inverse: While Social Annotation suffers from problems like, e. g., ambiguity or lack or precision, ontologies were especially designed to eliminate those. On the contrary, the latter suffer from a knowledge acquisition bottleneck, which is successfully overcome by the large user populations of Social Annotation Systems. Instead of being regarded as competing paradigms, the obvious potential synergies from a combination of both motivated approaches to "bridge the gap" between them. These were fostered by the evidence of emergent semantics, i. e., the self-organized evolution of implicit conceptual structures, within Social Annotation data. While several techniques to exploit the emergent patterns were proposed, a systematic analysis - especially regarding paradigms from the field of ontology learning - is still largely missing. This also includes a deeper understanding of the circumstances which affect the evolution processes. This work aims to address this gap by providing an in-depth study of methods and influencing factors to capture emergent semantics from Social Annotation Systems. We focus hereby on the acquisition of lexical semantics from the underlying networks of keywords, users and resources. Structured along different ontology learning tasks, we use a methodology of semantic grounding to characterize and evaluate the semantic relations captured by different methods. In all cases, our studies are based on datasets from several Social Annotation Systems. Specifically, we first analyze semantic relatedness among keywords, and identify measures which detect different notions of relatedness. These constitute the input of concept learning algorithms, which focus then on the discovery of synonymous and ambiguous keywords. Hereby, we assess the usefulness of various clustering techniques. As a prerequisite to induce hierarchical relationships, our next step is to study measures which quantify the level of generality of a particular keyword. We find that comparatively simple measures can approximate the generality information encoded in reference taxonomies. These insights are used to inform the final task, namely the creation of concept hierarchies. For this purpose, generality-based algorithms exhibit advantages compared to clustering approaches. In order to complement the identification of suitable methods to capture semantic structures, we analyze as a next step several factors which influence their emergence. Empirical evidence is provided that the amount of available data plays a crucial role for determining keyword meanings. From a different perspective, we examine pragmatic aspects by considering different annotation patterns among users. Based on a broad distinction between "categorizers" and "describers", we find that the latter produce more accurate results. This suggests a causal link between pragmatic and semantic aspects of keyword annotation. As a special kind of usage pattern, we then have a look at system abuse and spam. While observing a mixed picture, we suggest that an individual decision should be taken instead of disregarding spammers as a matter of principle. Finally, we discuss a set of applications which operationalize the results of our studies for enhancing both Social Annotation and semantic systems. These comprise on the one hand tools which foster the emergence of semantics, and on the one hand applications which exploit the socially induced relations to improve, e. g., searching, browsing, or user profiling facilities. In summary, the contributions of this work highlight viable methods and crucial aspects for designing enhanced knowledge-based services of a Social Semantic Web.
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The importance of medicinal plants and their use in industrial applications is increasing worldwide, especially in Brazil. Phyllanthus species, popularly known as quebra-pedras in Brazil, are used in folk medicine for treating urinary infections and renal calculus. This paper reports an authenticity study, based on herbal drugs from Phyllanthus species, involving commercial and authentic samples using spectroscopic techniques: FT-IR, ¹H HR-MAS NMR and ¹H NMR in solution, combined with chemometric analysis. The spectroscopic techniques evaluated, coupled with chemometric methods, have great potential in the investigation of complex matrices. Furthermore, several metabolites were identified by the NMR techniques.
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This study compared the mandibular displacement from three methods of centric relation record using an anterior jig associated with (A) chin point guidance, (B) swallowing (control group) and (C) bimanual manipulation. Ten patients aged 25-39 years were selected if they met the following inclusion criteria: complete dentition (up to the second molars), Angle class I and absence of signs and symptoms of temporomandibular disorders and diagnostic casts showing stability in the maximum intercuspation (MI) position. Impressions of maxillary and mandibular arches were made with an irreversible hydrocolloid impression material. Master casts of each patient were obtained, mounted on a microscope table in MI as a reference position and 5 records of each method were made per patient. The mandibular casts were then repositioned with records interposed and new measurements were obtained. The difference between the two readings allowed measuring the displacement of the mandible in the anteroposterior and lateral axes. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant differences (p>0.05) among the three methods for measuring lateral displacement (A=0.38 ± 0.26, B=0.32 ± 0.25 and C=0.32 ± 0.23). For the anteroposterior displacement (A=2.76 ± 1.43, B=2.46 ± 1.48 and C=2.97 ± 1.51), the swallowing method (B) differed significantly from the others (p<0.05), but no significant difference (p>0.05) was found between chin point guidance (A) and bimanual manipulation (C). In conclusion, the swallowing method produced smaller mandibular posterior displacement than the other methods.
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The national and Victorian burden of disease studies in Australia set out to examine critically the methods used in the Global Burden of Disease study to estimate the burden of mental disorders. The main differences include the use of a different set of disability weights allowing estimates in greater detail by level of severity, adjustments for comorbidity between mental disorders, a greater number of menta I disorders measured, and model ling of substance use disorders, anxiety disorders and bipolar disorder as chronic conditions. Uniform age-weighting in the Australian studies produces considerably lower estimates of the burden due to mental disorders in comparison with age-weighted disability-adjusted life years. A lack of follow-up data on people with mental disorders who are identified in cross-sectional surveys poses the greatest challenge in determining the burden of mental disorders more accurately.
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A study on the ecology of phlebotomine sandfly fauna in a restricted focus of cutaneous leishmaniasis in northern Venezuela was undertaken in order to investigate the species responsible for the transmission. The study area and catching methods for phlebotomine sandflies are described. A total of 9,061 females and 1,662 males were collected during a year-term study. 12 species of Lutzomya and 1 species of Brumptomya sp. were identified. Absolute and relative abundance and ocurrence for each species were determined. The rel ative occurrence allowed to distinguish the common species, viz. L. panamensis, L. ovallesi, L. gomezi, L. tinidadensis, L. atroclavata, L. cayennensis, L. shannoni and L. olmeca bicolor from the rare species vis., L. punctigeniculata, L. rangeliana, L. evansi and L. dubitans. General comments on the species composition of the sandfly fauna in this locality are made.
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The presence of acid fast bacilli in multiple specimens was investigated comparatively with Ziehl-Neelsen (ZN) and fluorescence microscopy (FM) staining in order to determine sensitivity in detecting tuberculosis (TB). A total of 465 specimens obtained from 295 patients were analysed at Harran University Medical School Hospital between March 1998 and March 2000. The culture was employed as the reference method. Sixty-eight patients (23.1%) were diagnosed as having TB by culture. The ZN and FM staining sensitivities were 67.6% (46/68) and 85.2% (58/68) respectively. Two hundred and one patients (68.1%) submitted one specimen to the laboratory. TB positivity was detected in 42 (20.9%) of these patients by culture. The sensitivities of ZN and FM stains were found to be 61% and 83% in these patients. However, in 18 patients (6.1%) who submitted two specimens to the laboratory, the TB was positive in six of them (33.3%) and ZN and FM sensitivities were 66% and 83% respectively. When three specimens or more were collected from the patients (76 patients, 25.8%), TB positivity was determined in 20 of them (26.3%) and the sensitivities were 80% and 92% in the ZN- and FM-stained smears, respectively. Our data indicate that in the diagnosis of TB, FM has greater sensitivity than ZN. In particular, in the case of a single specimen, the diagnostic value of FM is quite significant. It is, therefore, possible to conclude that both ZN and FM staining can be used for the diagnosis of TB when there are more than two specimens. However, if only one or two specimens are available, FM staining is preferable.
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This study compares the diagnostic accuracy of the TF-Test® (TFT) for human parasitosis with results obtained using the traditional Kato-Katz (KK), Hoffman-Pons-Janer (HPJ), Willis and Baermann-Moraes (BM) techniques. Overall, four stool samples were taken from each individual; three alternate-day TFT stool samples and another sample that was collected in a universal container. Stool samples were taken from 331 inhabitants of the community of Quilombola Santa Cruz. The gold standard (GS) for protozoa detection was defined as the combined results for TFT, HPJ and Willis coproscopic techniques; for helminth detection, GS was defined as the combined results for all five coproscopic techniques (TFT, KK, HPJ, Willis and BM). The positivity rate of each method was compared using the McNemar test. While the TFT exhibited similar positivity rates to the GS for Entamoeba histolytica/dispar (82.4%) and Giardia duodenalis (90%), HPJ and Willis techniques exhibited significantly lower positivity rates for these protozoa. All tests exhibited significantly lower positivity rates compared with GS for the diagnosis of helminths. The KK technique had the highest positivity rate for diagnosing Schistosoma mansoni (74.6%), while the TFT had the highest positivity rates for Ascaris lumbricoides (58.1%) and hookworm (75%); HPJ technique had the highest positivity rate for Strongyloides stercoralis (50%). Although a combination of tests is the most accurate method for the diagnosis of enteral parasites, the TFT reliably estimates the prevalence of protozoa and selected helminths, such as A. lumbricoides and hookworm. Further studies are needed to evaluate the detection accuracy of the TFT in samples with varying numbers of parasites.
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Background: The objective of the present study was to compare three different sampling and questionnaire administration methods used in the international KIDSCREEN study in terms of participation, response rates, and external validity. Methods: Children and adolescents aged 8–18 years were surveyed in 13 European countries using either telephone sampling and mail administration, random sampling of school listings followed by classroom or mail administration, or multistage random sampling of communities and households with self-administration of the survey materials at home. Cooperation, completion, and response rates were compared across countries and survey methods. Data on non-respondents was collected in 8 countries. The population fraction (PF, respondents in each sex-age, or educational level category, divided by the population in the same category from Eurostat census data) and population fraction ratio (PFR, ratio of PF) and their corresponding 95% confidence intervals were used to analyze differences by country between the KIDSCREEN samples and a reference Eurostat population. Results: Response rates by country ranged from 18.9% to 91.2%. Response rates were highest in the school-based surveys (69.0%–91.2%). Sample proportions by age and gender were similar to the reference Eurostat population in most countries, although boys and adolescents were slightly underrepresented (PFR <1). Parents in lower educational categories were less likely to participate (PFR <1 in 5 countries). Parents in higher educational categories were overrepresented when the school and household sampling strategies were used (PFR = 1.78–2.97). Conclusion: School-based sampling achieved the highest overall response rates but also produced slightly more biased samples than the other methods. The results suggest that the samples were sufficiently representative to provide reference population values for the KIDSCREEN instrument.