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487 Caiafa, A.N. and F.R. Martins. 2007. Taxonomic identification, sampling methods, and minimum size of the tree sampled implications and perspectives for studies in the Brazilian Atlantic

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Abstract  

This article introduced two sampling methods, including Directly Random Sampling (DRS) and Redistributed Random Sampling (RRS) methods for categorization of a large number of research articles retrieved from metallurgy and polymer subfields from the Science Citation Index (SCI) database. The accuracy of the proposed sampling methods was considered in association by comparing with reference results previously obtained by Fully Retrieving Sampling (FRS) method, which involved analyzing the contents and categories of all articles from the database. The results suggested that RRS and DRS methods were appropriate, efficient and reasonably accurate for categorization of relatively large volume of research articles. RRS method was highly recommended, especially when the contents of sample articles was unevenly distributed. By DRS and RRS methods, only about 6.3% of total articles were required for obtaining similar results as those given by FRS method. The percentage Expected Worst Errors (EWE) from DRS and RRS methods were observed to range from 1.0 to 5.5%. The EWE value could be reduced by increasing the sample size.

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An alternative way to use small filter paper strips as wicks for tiny flowers to collect floral nectar. This method is easily handling and gives a picture from the nectar sugar production during the day and during the flowering season under natural conditions. Disadvantageous of this way it cannot be used to measure the total nectar quantity but more closely the flower visitors’ tongue in picking up nectar.

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Investigations of trace elements in the atmosphere require the application of highly sensitive multielement analytical methods and methods allowing sampling of contrasting element speciations. Instrumental neutron activation analysis was used to determine 30 element concentrations in samples under investigation. The results of investigating properties of aerosol samples on filters and some aspects of the study of atmospheric trace-element vapor-gas and submicron aerosol phases are presented. A method for investigating the vapor-gas and submicron aerosol phases of atmospheric trace elements by sorption on collectors with neutron activation analysis of exposed collectors is offered.

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-1 using both a cone calorimeter and a new sampling method to complement the conventional sampling method [ 14 – 16 ]. For each material, the two methods were compared with respect to fire behavior. The aim of this study was to compare test methods for

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. Bringsén , A. , Ejlertsson , G. , Andersson , I. H. ( 2011 ): Flow situations during everyday practice in a medical hospital ward . Results from a study based on experience sampling method. BMC Nursing , 10 ( 3

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dataset, CSCD dataset has much larger size and it got a bigger exponent. Also, based on a small citation dataset Fanget al. ( 2007 ) got a smaller exponent than Price ( 1965 , 1976 ) and Redner ( 1998 ). The sampling method

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Information Act Policy. Using a systematic sampling method, an e-mail invitation with the link of the survey was sent to 6,000 students, accounting for one third of the student population. To increase the response rate, two reminder e-mails were sent to the

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Abstract  

Eighteen trace elements in biological material [grass /Imperata cylindrica/, mimosa plant /Mimosa pudica/, rice] by neutron activation method were determined. In the comparative analysis, we found the content of the same elements was different in the each material, although they were collected at the same place and the same sampling method was applied.

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Since the Groos droop of Bradford curves was reported, there has been a controversial explanation of its cause, i.e., that it is caused by an incomplete data set. In this study, a computer simulation was conducted to study the phenomenon. Incompleteness was characterized by two kinds of sampling, weighted and unweighted. Weighted sampling was used to simulate incompleteness of low productivity journals, unweighted sampling incompleteness at all productivity levels. Based on the result of 400 runs (two sampling methods x four sample sizes x ten data sets x five random runs), the hypothesis that the Groos droop is caused by incomplete data sets was rejected. The relationships between sample size, sampling method and the degree of the droop are also reported.

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