992 resultados para quantitative technique


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There are several studies on managing risks in information technology (IT) projects. Most of the studies identify and prioritise risks through empirical research in order to suggest mitigating measures. Although they are important to clients for future projects, these studies fail to provide any framework for risk management from IT developers' perspective. Although a few studies introduced a framework of risk management in IT projects, most of them are presented from clients' perspectives and very little effort has been made to integrate this with the project management cycle. As IT developers absorb a considerable amount of risk, an integrated framework for managing risks in IT projects from developers' perspective is needed in order to ensure success in IT projects. The main objective of the paper is to develop a risk management framework for IT projects from the developers' perspective. This study uses a combined qualitative and quantitative technique with the active involvement of stakeholders in order to identify, analyse and respond to risks. The entire methodology has been explained using a case study on an information technology project in a public sector organisation in Barbados.

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Purpose - The main objective of the paper is to develop a risk management framework for software development projects from developers' perspective. Design/methodology/approach - This study uses a combined qualitative and quantitative technique with the active involvement of stakeholders in order to identify, analyze and respond to risks. The entire methodology has been explained using a case study on software development project in a public sector organization in Barbados. Findings - Analytical approach to managing risk in software development ensures effective delivery of projects to clients. Research limitations/implications - The proposed risk management framework has been applied to a single case. Practical implications - Software development projects are characterized by technical complexity, market and financial uncertainties and competent manpower availability. Therefore, successful project accomplishment depends on addressing those issues throughout the project phases. Effective risk management ensures the success of projects. Originality/value - There are several studies on managing risks in software development and information technology (IT) projects. Most of the studies identify and prioritize risks through empirical research in order to suggest mitigating measures. Although they are important to clients for future projects, these studies fail to provide any framework for risk management from software developers' perspective. Although a few studies introduced framework of risk management in software development, most of them are presented from clients' perspectives and very little effort has been made to integrate this with the software development cycle. As software developers absorb considerable amount of risks, an integrated framework for managing risks in software development from developers' perspective is needed. © Emerald Group Publishing Limited.

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The fast developing international trade of products based on traditional knowledge and their value chains has become an important aspect of the ethnopharmacological debate. The structure and diversity of value chains and their impact on the phytochemical composition of herbal medicinal products has been overlooked in the debate about quality problems in transnational trade. Different government policies and regulations governing trade in herbal medicinal products impact on such value chains. Medicinal Rhodiola species, including Rhodiola rosea L. and Rhodiola crenulata (Hook.f. & Thomson) H.Ohba, have been used widely in Europe and Asia as traditional herbal medicines with numerous claims for their therapeutic effects. Faced with resource depletion and environment destruction, R. rosea and R. crenulata are becoming endangered, making them more economically valuable to collectors and middlemen, and also increasing the risk of adulteration and low quality. We compare the phytochemical differences among Rhodiola raw materials available on the market to provide a practical method for Rhodiola authentication and the detection of potential adulterant compounds. Samples were collected from Europe and Asia and nuclear magnetic resonance spectroscopy coupled with multivariate analysis software and high performance thin layer chromatography techniques were used to analyse the samples. A method was developed to quantify the amount of adulterant species contained within mixtures. We compared the phytochemical composition of collected Rhodiola samples to authenticated samples. Rosavin and rosarin were mainly present in R. rosea whereas crenulatin was only present in R. crenulata. 30% of the Rhodiola samples purchased from the Chinese market were adulterated by other Rhodiola spp. Moreover, 7 % of the raw-material samples were not labelled satifactorily. The utilisation of both 1H-NMR and HPTLC methods provided an integrated analysis of the phytochemical differences and novel identification method for R. rosea and R. crenulata. Using 1H-NMR spectroscopy it was possible to quantify the presence of R. crenulata in admixtures with R. rosea. This quantitative technique could be used in the future to assess a variety of herbal drugs and products. This project also highlights the need to further study the links between producers and consumers in national and trans-national trade.

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O presente estudo, sobre avaliação de aprendizagens, apesar de ser abordado por outros autores de variadas formas, esboça-se aqui com o tema A Avaliação da Aprendizagem na Escola Waldecy Corrêa: um estudo na terceira e quarta série do ensino fundamental I que tem como finalidade uma análise teórica e prática acerca da avaliação no processo de ensino e aprendizagem na escola supracitada. Essa abordagem constitui-se de extrema relevância para o entendimento da temática, haja vista, que a avaliação da aprendizagem ser um assunto bastante discutido entre os teóricos que postularam um significado com o propósito de nortear a base conceituai sobre o tema em estudo. Para embasar teoricamente foram imprescindíveis as ideias produzidas por alguns autores como Luckesi, Hoffmann, Perrenoud, Sant’Anna, Saul, além das políticas públicas como a LDB\ PCN's2, a Sistemática de Avaliação do Estado do Amapá entre outros, que focalizam a importância desta temática. Embora a estimativa produzida na presente pesquisas se traduza em efeitos de mudança na forma de aplicar a avaliação da aprendizagem com a realidade analisada. Os procedimentos metodológicos envolveram tanto a técnica qualitativa - articulada com o estudo de caso envolvendo como instrumentos na coleta de dados as observações e entrevistas, bem como a quantitativa como tratamento das informações recolhidas pela aplicação dos questionários para obtenção de resultados em consonância com nossos objetivos. As informações obtidas por meio dos resultados revelaram tendencialmente que os investigados estão perpassando de uma concepção de avaliação seletiva para uma avaliação de processo, embora tenha se observado alguns contrapontos. Nesse sentido, a proposta é que o professor busque ampliar o seu entendimento acerca da avaliação para que possa promover uma nova cultura do verdadeiro sentido do que, como, quando e para que avaliar. Dessa forma, a avaliação da aprendizagem se manifestará objetivando uma ação reflexiva e emancipatória dos sujeitos envolvidos em sua processualização. ABSTRACT: ln spite of being approached in several ways by other authors, the present study here outlines itself with the theme "The Evaluation of the Learning at Waldecy Corrêa School: a study in the third and fourth year of the primary education" and its purpose is a theoretical and practical analysis about the evaluation in the process of teaching and learning at the aforesaid school. This approach is constituted of extreme relevance for the understanding of the thematic in as much as the evaluation is a subject discussed a lot among the theorists who postulate a meaning with the purpose of guiding conceptual basis on the theme studied. The ideas produced by some authors, such as Luckesi, Hoffmann, Perrenoud, Sant'Anna, Saul, besides the public politics like the LDB\ PCN's2, the systematic of evaluation of the State of Amapá, among others that focus on the importance of this thematic were indispensable to give it basis theoretically. Although the estimate produced in the present research is translated into effect of change in the way of applying the evaluation in the learning together with the reality analyzed. The methodological procedures have involved the qualitative technique - articulated with the study of cases having as the tools in the data collection the observations and interviews - as well as the quantitative technique as treatment of the information collected by applying the questionnaires for obtaining the outcomes in harmony with our goals. The information obtained by the results has revealed the tendency that the investigated students are changing from a conception of selective evaluation to an evaluation of process. Although we have observed some counterpoints. ln this sense, the proposal is that the teacher looks for enlarging his understanding about the evaluation so that he can promote a new culture of the true sense of "what", "how", "when" and ''what for" to evaluate. This way, the evaluation of learning will be made known by aiming at a reflexive and emancipating action of the subjects involved in their processing.

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A clinical trial involving 80 patients of both sexes, from ages 15 to 55, with chronic intestinal or hepatointestinal schistosomiasis mansoni, was carried out to evaluate the therapeutical efficacy of different dose regimens of praziquantel. The patients were randomly allocated into four groups with an equal number of cases and were then treated with one of the following dosages: 60 mg/kg for 1 day; 60 mg/kg daily for 2 days; 60 mg/kg daily for 3 days; and 30 mg/kg daily for 6 days. The assessment of parasitological cure was based on the quantitative oogram technique through rectal mucosa biopsies which were undertaken prior to, as well as, 1,2,4 and 6 months post-treatment. Concurrently, stool examinations according to the qualitative Hoffman, Pons & Janer (HPJ) and the quantitative Kato-Katz (K-K) methods were also performed. The best tolerability was observed with 30 mg/kg daily for 6 days whereas the highest incidence of side-effects (mainly dizziness and nausea) was found with 60 mg/kg daily for 3 days. No serious adverse drug reaction has occurred. The achieved cure rates were: 25% with 60 mg/kg for 1 day; 60% with 60 mg/kg daily for 2 days; 89.5% with 60 mg/kg daily for 3 days; and 90% with 30 mg/kg daily for 6 days. At the same time there has been a downfall of 64%, 73%, 87% and 84% respectively, in the median number of viable S. mansoni ova per gram of tissue. Thus, a very clear direct correlation between dose and effect could be seen. The corresponding cure rates according to stool examinations by HPJ were 39%, 80%, 100% and 95%; by K-K 89%, 100%, 100% and 100%. This discrepancy in results amongst the three parasitological methods is certainly due to their unequal accuracy. In fact, when the number of viable eggs per gram of tissue fell below 5,000 the difference in the percentage of false negative findings between HPJ (28%) and K-K (80%) became significative. When this number dropped to less than 2,000 the percentage of false negative results obtained with HPJ (49%) turned significant in relation to the oogram as well. In conclusion, it has been proven that praziquantel is a highly efficacious agent against S. mansoni infections. If administered at a total dose of 180 mg/kg divided into either 3 or 6 days, it yields a 90% cure rate. Possibly, one could reach 100% by increasing the total dose to 240 mg/kg. Furthermore, it was confirmed that the quantitative oogram technique is the most reliable parasitological method when evaluating the efficacy of new drugs in schistosomiasis mansoni.

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We have developed a digital holographic microscope (DHM), in a transmission mode, especially dedicated to the quantitative visualization of phase objects such as living cells. The method is based on an original numerical algorithm presented in detail elsewhere [Cuche et al., Appl. Opt. 38, 6994 (1999)]. DHM images of living cells in culture are shown for what is to our knowledge the first time. They represent the distribution of the optical path length over the cell, which has been measured with subwavelength accuracy. These DHM images are compared with those obtained by use of the widely used phase contrast and Nomarski differential interference contrast techniques.

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Quantitative phase microscopy (QPM) has recently emerged as a new powerful quantitative imaging technique well suited to noninvasively explore a transparent specimen with a nanometric axial sensitivity. In this review, we expose the recent developments of quantitative phase-digital holographic microscopy (QP-DHM). Quantitative phase-digital holographic microscopy (QP-DHM) represents an important and efficient quantitative phase method to explore cell structure and dynamics. In a second part, the most relevant QPM applications in the field of cell biology are summarized. A particular emphasis is placed on the original biological information, which can be derived from the quantitative phase signal. In a third part, recent applications obtained, with QP-DHM in the field of cellular neuroscience, namely the possibility to optically resolve neuronal network activity and spine dynamics, are presented. Furthermore, potential applications of QPM related to psychiatry through the identification of new and original cell biomarkers that, when combined with a range of other biomarkers, could significantly contribute to the determination of high risk developmental trajectories for psychiatric disorders, are discussed.

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This paper describes the importance of an innovative analytical technique for drugs and pharmaceuticals quantification, using Fouriertransform infrared (FTIR) transmission spectroscopy. This method does not use organic solvents, which is one great advantage over the most common analytical methods. This fact contributes to minimize the generation of organic solvent waste by the industry and thereby reduces the impact of its activities on the environment. The method involved absorbance measurements of the band corresponding to one of the chosen group in the molecule. Obviously, the method should be validated according to ICH guidelines, showing linearity, precision, accuracy and robustness, over a concentration range, using small amounts to prepare the analyte. The validated method is able to quantify drugs and pharmaceuticals and can be used as an environmentally friendly alternative for the routine analysis in pharmaceutical industry quality control.

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This article contributes to an ongoing debate about how to measure sensitive topics in population surveys. We propose a novel technique that can be applied to the measurement of quantitative sensitive variables: the item sum technique (IST). This method is closely related to the item count technique, which was developed for the measurement of dichotomous sensitive items. First, we provide a description of our new technique and discuss how data collected by the IST can be analyzed. Second, we present the results of a CATI survey on undeclared work in Germany, in which the IST has been applied. Using an experimental design, we compare the IST to direct questioning. Our empirical results indicate that the IST is a promising data-collection technique for sensitive questions. We conclude by discussing the limitations of the new technique and outlining possible improvements for future studies.

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A new surface analysis technique has been developed which has a number of benefits compared to conventional Low Energy Ion Scattering Spectrometry (LEISS). A major potential advantage arising from the absence of charge exchange complications is the possibility of quantification. The instrumentation that has been developed also offers the possibility of unique studies concerning the interaction between low energy ions and atoms and solid surfaces. From these studies it may also be possible, in principle, to generate sensitivity factors to quantify LEISS data. The instrumentation, which is referred to as a Time-of-Flight Fast Atom Scattering Spectrometer has been developed to investigate these conjecture in practice. The development, involved a number of modifications to an existing instrument, and allowed samples to be bombarded with a monoenergetic pulsed beam of either atoms or ions, and provided the capability to analyse the spectra of scattered atoms and ions separately. Further to this a system was designed and constructed to allow incident, exit and azimuthal angles of the particle beam to be varied independently. The key development was that of a pulsed, and mass filtered atom source; which was developed by a cyclic process of design, modelling and experimentation. Although it was possible to demonstrate the unique capabilities of the instrument, problems relating to surface contamination prevented the measurement of the neutralisation probabilities. However, these problems appear to be technical rather than scientific in nature, and could be readily resolved given the appropriate resources. Experimental spectra obtained from a number of samples demonstrate some fundamental differences between the scattered ion and neutral spectra. For practical non-ordered surfaces the ToF spectra are more complex than their LEISS counterparts. This is particularly true for helium scattering where it appears, in the absence of detailed computer simulation, that quantitative analysis is limited to ordered surfaces. Despite this limitation the ToFFASS instrument opens the way for quantitative analysis of the 'true' surface region to a wider range of surface materials.