1,720,963 research outputs found
Development of an evanescent wave-based optical microfiber platform for label-free sensing applications
No full textDespite the advantages of optical microfiber for sensing applications, its potential use of for real applications is often undervalued owing to its fragile characteristic that requires delicate handling and the bulky and costly optical setup. The work presented in this thesis aims to bridge this research gap by developing a miniaturized optical microfiber-based sensor device that also serves as an economical alternative to conventional lab-based test equipment without compromising the detection sensitivity. This thesis focuses on the fabrication of a compact handheld sensor device using surface-functionalized optical microfiber for water contaminant and gas sensing applications. Due to the versatile chemical surface modification of the optical microfiber and the compact interrogator design to ease the translation into a portable device, this work has made a huge improvement and given rise to a new trend in the field of optical fiber-based chemical sensing.Doctor of Philosoph
Optical microfiber sensor for heavy metal ion detection
No full textHeavy metal pollution in water environment poses a serious threat and of great environmental concern because they cannot be degraded or destroyed completely. In fact, heavy metal tends to accumulate over time within the living organism and the rate of accumulation can be faster than they are excreted. Therefore, continuous monitoring of the level of heavy metal contaminants in water resources is crucial to keep them below the standard maximum permissible limit of the particular geographical area. Addressing this matter, an optical tapered fiber that is well known for excellent sensing capabilities due to the strong evanescent field in the tapered region was adapted in this study to measure different concentrations of the metal ion in an aqueous environment. Tapered fiber with a waist diameter of 7.1 micrometer was used and the surface of the tapered region was functionalized with the amine group in order to form a strong covalent bond between the amine and the carboxylic group of a compound known as chelating agents. The chelating agent is capable of binding metal ions to form stable metal chelates, thus, when metal ions are bound to the surface of the tapered region, there will be some changes in refractive index around the tapered region. These changes can result in the alteration of the characteristic of light passing through the tapered region.MASTER OF ENGINEERING (EEE
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Functionalized Fiber End Superstructure Fiber Bragg Grating Refractive Index Sensor for Heavy Metal Ion Detection
No full textWe present a novel superstructure fiber Bragg grating fiber end sensor capable of detecting variations in refractive index (RI) of liquids and potentially that of gases, and demonstrated an application in the detection of heavy metal ions in water. The sensor is capable of sensing RI variations in the range of 1.333 to 1.470 with good sensitivity of up to 230 dB/RIU achieved for the RI range of 1.370 to 1.390. The sensor is capable of simultaneously measuring variations in ambient temperature along with RI. A simple chemical coating was employed as a chelating agent for heavy metal ion detection at the fiber end to demonstrate an possible application of the sensor. The coated fiber sensor can conclusively detect the presence of heavy metal ions with concentrations upwards of 100 ppm. RI sensing capability of the sensor is neither affected by temperature nor strain and is both robust and easily reproducible
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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