1,720,962 research outputs found
Plastic Concrete Transportation Techniques on Construction Sites: A Comparative Productivity Study
Get PDFTarget outputs on construction operations are of paramount importance to productivity studies in the built environment. The objective of this study therefore was to determine the target outputs of various methods of placing plastic concrete on construction sites as information for benchmarking concreting productivity in the Nigeria built environment. Using Lagos state as the study area, concreting operations were examined in 64 building construction sites spanning large-sized, medium-sized and small-sized construction companies with 8,34 and 22 projects respectively. Using stratified random sampling, 25 of the 64 sites were selected for investigation and were made up of 5, 10, 10 sites for the respective large, medium and small-sized construction firms. The study was limited to bungalows and single storey residential, commercial and office building sites managed by construction companies registered with the Federal or Lagos State Ministry of Works only. A total of 167 daily concrete pours was observed on the 25 construction sites at an average of 6 days per site. Data collected included placing method, location/type of concrete pours, quantity of concrete placed, overall pour time, number of operatives engaged, and actual duration of concreting, distance to pour location, weather and delay time. The results showed that the four main concrete placing techniques used in Lagos State were cranes, dumpers, wheelbarrows, and head pans. The mean overall concreting productivity of cranes was 11.24 m3/hr compared to 8.53 m3/hr by dumpers, 6.69 m3/hr by wheelbarrows and 3.21 m3/hr by head pans. The labour productivity for concreting by cranes was 4.09 whr/m3 as against 5.13 whr/m3 for dumpers, 9.74 whr/m3 for wheelbarrows and 12.11 whr/m3 for head pans. The productivities were in the ratio of 4:3:2:1 for cranes, dumpers, wheelbarrows, and head pans respectively. The results have significant bearing for contractor’s method statement and tend to guide construction clients in adjudicating tenders for selecting the contractor who can best manage the technical risk associated with the construction project. Keywords: Plastic concrete, transportation techniques, construction sites, productivity
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Get PDFWe 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
Moving Nigeria’s Project Procurement System to Best Value: A Prescription
Get PDFA new sustainable and best value procurement initiative suitable for use in developing countries has been developed. The procurement system, the Performance Information Procurement System (PIPS) was developed in the United States (US), and has been tested in Botswana and recently in India. PIPS not only stabilizes the procurement system, it transfers the risk and control to contractors who must act in the best interest of the client. The transparency, accountability, and risk management orientation of the PIPS structure disengages relationships, inaccurate expectations, and bureaucratic and political actions. The strength of PIPS includes minimizing the need for professionals representing the client to make decisions, direct, and control contractors. PIPS has been tested for 20 years in the US, with 98% performance on over 600 projects. Recent tests outside of construction reveal that the efficiency of PIPS can minimize up to 50% of the procurement transaction costs. We hypothesized that paradigm shift from the low-bid or price-based procurement to the best value procurement through the application of PIPS technology is a potential panacea capable of extricating corruption, collusion, fraud, bid rigging, ethical violations and negative headlines from developing countries’ procurement environment rather than advancing measures that only scratches the problems on the surface. We infer that a adoption of a new initiative in best value procurement using PIPS technology can revolutionize the procurement environment in Nigeria in particular and the developing countries as a whole. Keywords: Best value, public project procurement, Performance Information Procurement System (PIPS), sustainable consumption, developing countries, Nigeria
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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