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Usability of fractometer for the purpose of a practical preliminary assessment tool for wood density of Pinus brutia
No full textEl fractómetro es un dispositivo que rompe núcleos incrementales para medir la resistencia a la fractura. Las ventajas del dispositivo son que es relativamente rápido, fácil de usar en el campo y puede realizar mediciones de resistencia directa en núcleos incrementales. El objetivo principal del estudio fue evaluar la usabilidad del fractómetro como herramienta de evaluación preliminar para las características de densidad de la madera de árboles turcos en pie de Pinus brutia (pino rojo). La resistencia a la fractura se midió en núcleos con incrementos de 5 mm de diámetro y se utilizó densitometría de rayos X para las mediciones de densidad. Debido a la alta correlación entre los dos rasgos (fractura y densidad), se construyó un modelo mediante regresión lineal. Se tomaron muestras de cincuenta árboles para construir el modelo estadístico (r2: 0,74) y se utilizó un tamaño de muestra igual para probar el modelo. El valor de densidad obtenido del modelo fue de 0,546 gcm-3, mientras que el valor de densidad promediado por el método de rayos X para el mismo grupo fue de 0,543 gcm-3. Al considerar los valores medios, se puede decir que el modelo proporciona una buena predicción. Según la experiencia personal y los resultados de la investigación, algunos árboles exhibieron mejores características de crecimiento y calidad de la madera que otros. El mejoramiento genético a partir de estos árboles podría ofrecer mejoras en la producción de madera y el rendimiento del Pinus brutia (pino rojo). Como consecuencia general, el fractómetro y el muestreo incremental de núcleos se pueden utilizar en programas de mejoramiento genético de pinos para la evaluación preliminar de la densidad de la madera.The fractometer is a device that breaks increment cores to measure fracture strength. The advantages of the device are that it is relatively fast, easy to use in the field, and it can perform direct strength measurements on increment cores. The main purpose of the study was to evaluate the usability of the fractometer as a preliminary evaluation tool for wood density traits of standing Turkish Pinus brutia (red pine) trees. Fracture strength was measured on 5 mm diameter increment cores, and X-ray densitometry was used for density measurements. Due to the high correlation between the two traits (fracture and density), a model was built using linear regression. Fifty trees were sampled to build the statistical model (r2: 0,74), and an equal sample size was used to test the model. The density value obtained from the model was 0,546 gcm-3, while the density value averaged by the X-ray method for the same group was 0,543 gcm-3. When considering mean values, it can be said that the model provides a good prediction. Based on personal experience and research results, some trees exhibited better growth and wood quality traits than others. Breeding from these trees could offer improvement in timber production and performance for Pinus brutia (red pine). As a general consequence, the fractometer and increment core sampling can be used for pine tree breeding programs for the preliminary assessment of wood density
Usability of fractometer for the purpose of a practical preliminary assessment tool for wood density of Pinus brutia
Full text linkThe fractometer is a device that breaks increment cores to measure fracture strength. The advantages of the device are that it is relatively fast, easy to use in the field, and it can perform direct strength measurements on increment cores. The main purpose of the study was to evaluate the usability of the fractometer as a preliminary evaluation tool for wood density traits of standing Turkish Pinus brutia (red pine) trees. Fracture strength was measured on 5 mm diameter increment cores, and X-ray densitometry was used for density measurements. Due to the high correlation between the two traits (fracture and density), a model was built using linear regression. Fifty trees were sampled to build the statistical model (r2: 0,74), and an equal sample size was used to test the model. The density value obtained from the model was 0,546 gcm-3, while the density value averaged by the X-ray method for the same group was 0,543 gcm-3. When considering mean values, it can be said that the model provides a good prediction. Based on personal experience and research results, some trees exhibited better growth and wood quality traits than others. Breeding from these trees could offer improvement in tim- ber production and performance for Pinus brutia (red pine). As a general consequence, the fractometer and increment core sampling can be used for pine tree breeding programs for the preliminary assessment of wood density
Non-destructive estimation of wood density in standing Pinus brutia trees using the drilling resistance method: Results and insights
No full textIn recent years, the use of drilling resistance method and devices which operate based on the method for non-destructive evaluation of wood has expanded, but research for density evaluation on standing trees remains limited. The study aimed to assess the effectiveness of the method through a device (IML RESI F500-S) in estimating wood density for standing Turkish red pine (Pinus brutia) trees. Increment core samples and measurement data were collected from stands of various ages and types in the Mediterranean region of Türkiye. Wood density data determined by x-ray densitometry were compared with estimates derived from charts of the device. The effect of drilling path direction was investigated on a group. Results showed that linear modelling by using the device data (obtained only by following the device manual) was moderately successful (r2≈0,62) in estimating density for only a sampling group (S1: Consisting of trees at different age, on different diameter etc.; range of density: 0,270 g/cm3; coefficient of variation:11 %). However, the other investigated group (S2), which had lower density variation due to less individual differentiation in terms of age, diameter etc., did not reveal a successful linear model. Solely the results for the subgroup 6th, showing lower density range than S1, demonstrated that even with lower density variation (cv≈7 %), standing tree wood density could be non-destructively estimated by a linear model (r2=0,72) using the device data. However, the data of the group obtained by using increment cores to ensure proper alignment of the drilling. In this case accurate estimation required a drilling path perpendicular to annual rings and passing through the pith, but the current form of the device or such devices are unable to meet the requirement. The drilling resistance method has potential use in tree selection. To improve the device's accuracy, future research should focus on developing techniques or modifications of such device to ensure more consistent and reliable drilling paths for standing trees
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
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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