Dissertations / Theses on the topic 'Blackbutt'

The impact of the variability in timber properties has been a challenge for companies involved in drying timber, which have to handle these variations and at the same time meet the requirements stated in the Australian/New Zealand Standard for the assessment of dried timber quality (2001). The definition of quality considered in this study is to both minimize the dispersion of the final moisture contents in dried timber boards, and to reduce cracking/checking. Anecdotal evidence also suggests that the timber properties of plantation timber appear to be more variable compared with the properties of old growth or regrowth timber. Therefore, this thesis focuses on measuring the amount of variability of timber properties by conducting drying experiments using timber boards taken from different locations within a single tree and between trees, for regrowth and plantation blackbutt timber (Eucalyptus pilularis Sm.). The quantified variabilities were then used to develop optimized timber drying schedules that are intended to dry regrowth and plantation blackbutt boards as quickly as possible (highest productivity) without cracking (quality loss) in the presence of large biological variability. Blackbutt (Eucalyptus pilularis Sm.) was the chosen species for this thesis because of its abundance in New South Wales. It is considered to be one of the most important eucalypts for planting in NSW. It has superior growth and high survival rates compared with other eucalyptus species, and the timber is marketable. Lastly, conventional kiln drying was considered in this thesis compared with other drying methods such as air drying and solar kilns due to (arguably) better control of the drying conditions and faster throughput in conventional drying. The higher costs of conventional kiln drying are compensated, relative to open—air drying, by the reduction in stock level and faster turnaround of green to dried timber. Firstly, an overview of previous work on the development and evaluation of different drying schedules was given. Previous work either developed optimized drying schedules to minimize the dispersion of the final moisture contents, or reduced cracking/checking. No schedule has been developed to satisfy both aspects of quality. In addition, only one report has taken into consideration biological variability in the development of an optimized drying schedule, but this approach has not been tested experimentally. In addition, the information on the variability of biological parameters was very limited, was assumed to be normally distributed, and the parameters were assumed to be uncorrelated with one another. There is little information about the variability in timber properties with respect to drying, including how strongly they are correlated. This thesis has particularly addressed this aspect of the problem. Drying experiments using conventional kiln drying were conducted. The properties of two regrowth blackbutt logs (36 boards) and two plantation blackbutt logs (24 boards), have been measured and analysed for the within—tree variation of timber properties. In a separate set of experiments, two boards were taken from each log, from a total of 12 regrowth logs and 10 plantation logs, to study the between—tree variability of the timber properties of blackbutt timber. The timber properties measured consisted of the basic density, the initial moisture content, the diffusion coefficient, the failure strain, the failure stress, the modulus of elasticity and the shrinkage. The amount of cracking or checking and the dispersion of final moisture contents were assessed. 90% of the regrowth timber and 90% of the plantation timber fell in the Class C quality for surface checking, regrowth timber fell in Class B for end checking, while the end checks in the plantation timber fell in Class C for quality. Regrowth timber therefore appeared here to have slightly better quality than plantation material when dried with the same drying schedule, as here, in agreement with anecdotal suggestions that plantation material is more difficult to dry well. 95% of both the regrowth and the plantation timber fell in Class E quality for internal checking. Overall, along with the assessment that both regrowth and plantation timber was Class C quality for the variation of final moisture contents, these regrowth timber boards and the plantation timber boards fell in the lower quality classes for the criteria of checking and target moisture content for appearance products. Quality Classes A and B are higher quality categories, for appearance—grade products. The dispersion of the final moisture contents was greater with the plantation blackbutt timber (0.24 within; 0.36 between) than with the regrowth blackbutt timber (0.19 within; 0.15 between) for both within—tree and between—trees variability, respectively. In general, the diffusion coefficients for the timber in this thesis ranged between 1.14×10—10 and 6.77×10—10 m2s—1. There was a significant difference between the diffusion coefficients of the plantation and regrowth blackbutt timber for the within—tree test at a 0.05 significance level. The variation in the diffusion coefficients within a single plantation blackbutt log was higher than the variation in the diffusion coefficients within a regrowth blackbutt log. In addition, there was also a significant difference between the diffusion coefficients of regrowth and plantation blackbutt timber at a 0.05 significance level for between—trees variability. The initial moisture contents, the diffusion coefficient, and shrinkage decreased from pith to bark and the basic density and the modulus of elasticity (MOE) increased in the same direction, within a tree, for both regrowth and plantation blackbutt. The results of the analysis of variance (ANOVA) showed that radial and circumferential effects were significant sources of the within—tree variations for the diffusion coefficient, the initial moisture content, the basic density, the failure strain, the failure stress, the modulus of elasticity and shrinkage. A similar result was found for the ANOVA between trees. The ANOVA results also indicated that the smaller—sized samples used for the analysis (i.e. sub—samples of eight boards for the within—tree test of regrowth blackbutt, sub—samples of four boards for the between—trees test of regrowth blackbutt, sub—samples of six boards for the within—tree test of plantation blackbutt, and sub—samples of six boards for the between—trees test of plantation timber) were sufficient to measure the key effects adequately for the variabilities of the physical, transport, and mechanical properties, provided that all combinations of sub—samples were considered. There was no significant difference between the ANOVA results for these smaller sized samples (less than 1% change), considering all combinations, and the ANOVA results for the ‘full’ board cases. Though the sample sizes were unusually small to represent population statistics by most standards, all combinations of the sub-sets were assessed and an averaged picture of the situation with smaller sample sizes was given. Moreover, MOEs (both green and kiln—dried states) of plantation blackbutt were lower compared with the MOE of regrowth blackbutt. It is possible that the MOE was correlated with the basic density, and the basic density of regrowth blackbutt was higher than the basic density of plantation blackbutt. The shrinkage in the tangential direction was approximately twice the amount of radial shrinkage. The ranges of the measured radial shrinkage values were 0.024 – 0.094 mm mm-1 for regrowth blackbutt and 0.037 – 0.125 mm mm-1 for plantation blackbutt. The higher shrinkage values for plantation blackbutt timber show that plantation material is less stable dimensionally, and this situation is possibly due to the high juvenile wood content and low basic density. These differential (tangential:radial) shrinkage values ranged from 1.12 – 2.93 for regrowth blackbutt and 1.09 – 2.92 for plantation blackbutt. Tests were conducted to determine the degree of statistical normality for the distribution of each property (physical, transport, and mechanical). The results of the normality tests showed that most timber properties for regrowth and plantation blackbutt timber were distributed normally on a linear scale based on the W test, both within and between—trees. On the other hand, some timber properties showed a better fit with the three—parameter lognormal distribution, such as the diffusion coefficient and the green failure strain for within—tree variability of regrowth timber. The means and standard deviations of these distributions were further analysed by applying significance tests at a 0.05 level. For regrowth blackbutt, the data for the initial moisture content, the basic density, the diffusion coefficient, and shrinkage showed no significant differences, comparing the cases within and between—trees. The mechanical behaviour, however, was significantly different between each group and suggested that the two regrowth trees used for the within—tree test were stiffer than the 12 trees used for the between—trees test. It was possible that the mechanical properties were dependent on the geographic location where the tree was felled, and the heartwood content of each log. On the other hand, since all the plantation logs used for the within and between—trees tests were taken from one location, the mechanical properties were not significantly different within the plantation sample. The silviculture and the age of all the plantation trees were the same, which might have contributed to the small variation of the timber properties between the within—tree and between—trees cases for plantation material. Lastly, a significance test was conducted to compare the properties of regrowth and plantation blackbutt timber. Most timber properties (except for the initial moisture content) were significantly different between regrowth and plantation blackbutt. Plantation blackbutt timber had a lower basic density, higher diffusion coefficient and shrinkage, and the modulus of elasticity (both in its green and dried states) was lower compared with regrowth blackbutt timber. In addition to geographic location, heartwood/juvenile content, maturity (age), and differences in microfibril angle may have affected these timber properties in plantation blackbutt timber. For all the experiments, the possibility that there is a correlation between high initial moisture contents, higher diffusion coefficients, low basic densities, and low green modulus of elasticity’s (MOE) was assessed using principal components analysis (PCA). A principal components analysis was performed on the four parameters: the basic density, the initial moisture content, the diffusion coefficient, and the green MOE. The results of the PCA showed that the principal component for the within—tree and between—trees test accounted for 93% and 94% (for regrowth), and 92% and 90% (for plantation), respectively, of the total amount of variation within these parameters, giving some support for the mentioned correlation between the parameters. The strong correlation between the diffusion coefficient and the basic density, D; the diffusion coefficient and the initial moisture content, Xi; and the diffusion coefficient, D, and the modulus of elasticity, EG were represented by empirical equations. The F significance test was conducted to determine if the equations from the within—tree and between—trees tests, and the regrowth blackbutt and plantation blackbutt tests, were significantly different. The difference between the equations for the within—tree and between—trees variability of plantation blackbutt timber (Factual= 1.35  Fexpected= 2.13) was the only result that showed no significant difference. A possible reason for this finding is that the boards from the within—tree and between—tree variability tests, hence the trees, were all felled from one location. On the other hand, the other tests compared boards that were taken from trees felled from different locations, including the regrowth blackbutt within trees, compared with between trees. The results of the significance tests imply that boards taken from one location, whether they are within—tree and between—tree samples, have probably come from the same overall population. Hence using any of the correlations (within—tree or between—trees for plantation blackbutt) would be suitable to estimate the diffusion coefficient of other plantation blackbutt samples at the same location. Overall, these empirical equations can be used to estimate important drying properties of other regrowth and plantation blackbutt samples, such as the diffusion coefficient, using easily measured properties, like the initial moisture content or the basic density, as long as the boards are taken from the same age group (i.e. regrowth or plantation) and the same location. Thereafter, the blackbutt timber boards may be segregated based on the range of diffusion coefficients as estimated from the densities or the initial moisture contents. Hence a suitable drying schedule should be chosen for each segregated group. Collapse was not significant for blackbutt samples studied in this thesis, and possibly this timber species in general, but it may be significant for other eucalyptus species such as collapse—prone Eucalyptus regnans F. Muell (mountain ash) This potential limitation means that care is needed in applying the relationships found in this thesis to collapse—prone species. The same drying model was used to assess the effects of different drying schedules (i.e. increasing and decreasing the dry—bulb and wet—bulb temperatures of the original drying schedule by 5oC and 10oC) and of the potential correlations between the diffusion coefficient, the green MOE, the shrinkage coefficient (calculated from the tangential shrinkage), and the initial moisture content on the variability of final moisture contents, when the average moisture content within a stack of timber reached 15%. In addition, the maximum strain attained by the timber boards was also predicted. The results show that for regrowth blackbutt timber and accounting for within—tree variability, there was no relationship between the length of the drying schedule and the dispersion of final moisture contents. As the temperatures increased, the dispersion of the final moisture contents showed no consistent trend. The absence of a clear trend may be due to the different locations where the logs used for the within—tree test of regrowth variability were taken. On the other hand, the between—tree variability sensitivity tests for both regrowth and plantation blackbutt timber and the within—tree variability sensitivity test for plantation blackbutt timber show a relationship between the length of the drying schedule and the dispersion of final moisture contents. The dispersion of the final moisture contents decreased as temperatures increased. Generally, the ‘+10oC’ drying schedule gave the shortest time for the stack of timber to reach the target average moisture content, and its conditions produced the smallest dispersion of final moisture contents. It was also observed, however, for all sensitivity tests, that as the temperature of the drying schedule increased, the average predicted values decreased for the maximum strains reached. This is a very unusual result, because normally the strains and stresses would be expected to increase with increasing temperature. A possible reason for this is that within a piece of timber, as the temperatures increase, the diffusion coefficient will increase because the internal average temperature increases, so the internal resistance to mass transfer decreases, which leads to the moisture content gradient decreasing, even though the drying rate may slightly increase. This decreases both the drying time and the maximum strain reached as the temperature increases. There are limitations, however, associated when using high temperatures in kiln drying such as collapse and timber discolouration. The optimization technique created by Pordage (2006) was improved by using a large number of measurements to quantify the variability in the properties of blackbutt timber. The first simulation accounted for the between—tree variability of the biological parameters in regrowth blackbutt, and the second simulation accounted for both the within and between—tree variability of the timber properties in plantation blackbutt. Since location was observed as a main source of variability, the timber properties used for each simulation were taken from the logs that were felled from the same location. The mean and the standard deviations of the initial moisture content, the reference diffusion coefficient, and the shrinkage coefficient of regrowth and plantation blackbutt timber boards measured in the actual drying experiments, along with the covariance between these properties represented by a covariance matrix, were used for each simulation. The total drying time of the optimized drying schedule of plantation blackbutt timber was longer (an additional 168 hours, i.e. 472 hours) compared with the total drying time of the optimized drying schedule of regrowth blackbutt timber (304 hours). Due to the greater variability present in plantation blackbutt, slower drying is required. Moreover, the total drying times from the ‘regrowth blackbutt’ optimization and the ‘plantation blackbutt’ optimization (which both accounted for variability) were shorter compared with the total drying time of the original drying schedule for 28 mm—thick mixed—sawn blackbutt boards, i.e. 504 hours. On the other hand, the total drying times of the optimized drying schedules of regrowth and plantation blackbutt timber were greater than the total drying time (152 hours) predicted by Pordage’s (2006) optimized drying schedule accounting for the variability of Eucalyptus paniculata (grey ironbark). He had limited information on the variability of the parameters of grey ironbark and thus used an estimate from another eucalyptus species, Eucalyptus obliqua (messmate), whereas in this thesis, the variabilities for regrowth and plantation blackbutt used for the optimization technique were measured and part of the scope for this study. Overall, this is a typical application of the data obtained in this thesis to the optimization of drying schedules.

Doctor of Philosophy
The impact of the variability in timber properties has been a challenge for companies involved in drying timber, which have to handle these variations and at the same time meet the requirements stated in the Australian/New Zealand Standard for the assessment of dried timber quality (2001). The definition of quality considered in this study is to both minimize the dispersion of the final moisture contents in dried timber boards, and to reduce cracking/checking. Anecdotal evidence also suggests that the timber properties of plantation timber appear to be more variable compared with the properties of old growth or regrowth timber. Therefore, this thesis focuses on measuring the amount of variability of timber properties by conducting drying experiments using timber boards taken from different locations within a single tree and between trees, for regrowth and plantation blackbutt timber (Eucalyptus pilularis Sm.). The quantified variabilities were then used to develop optimized timber drying schedules that are intended to dry regrowth and plantation blackbutt boards as quickly as possible (highest productivity) without cracking (quality loss) in the presence of large biological variability. Blackbutt (Eucalyptus pilularis Sm.) was the chosen species for this thesis because of its abundance in New South Wales. It is considered to be one of the most important eucalypts for planting in NSW. It has superior growth and high survival rates compared with other eucalyptus species, and the timber is marketable. Lastly, conventional kiln drying was considered in this thesis compared with other drying methods such as air drying and solar kilns due to (arguably) better control of the drying conditions and faster throughput in conventional drying. The higher costs of conventional kiln drying are compensated, relative to open—air drying, by the reduction in stock level and faster turnaround of green to dried timber. Firstly, an overview of previous work on the development and evaluation of different drying schedules was given. Previous work either developed optimized drying schedules to minimize the dispersion of the final moisture contents, or reduced cracking/checking. No schedule has been developed to satisfy both aspects of quality. In addition, only one report has taken into consideration biological variability in the development of an optimized drying schedule, but this approach has not been tested experimentally. In addition, the information on the variability of biological parameters was very limited, was assumed to be normally distributed, and the parameters were assumed to be uncorrelated with one another. There is little information about the variability in timber properties with respect to drying, including how strongly they are correlated. This thesis has particularly addressed this aspect of the problem. Drying experiments using conventional kiln drying were conducted. The properties of two regrowth blackbutt logs (36 boards) and two plantation blackbutt logs (24 boards), have been measured and analysed for the within—tree variation of timber properties. In a separate set of experiments, two boards were taken from each log, from a total of 12 regrowth logs and 10 plantation logs, to study the between—tree variability of the timber properties of blackbutt timber. The timber properties measured consisted of the basic density, the initial moisture content, the diffusion coefficient, the failure strain, the failure stress, the modulus of elasticity and the shrinkage. The amount of cracking or checking and the dispersion of final moisture contents were assessed. 90% of the regrowth timber and 90% of the plantation timber fell in the Class C quality for surface checking, regrowth timber fell in Class B for end checking, while the end checks in the plantation timber fell in Class C for quality. Regrowth timber therefore appeared here to have slightly better quality than plantation material when dried with the same drying schedule, as here, in agreement with anecdotal suggestions that plantation material is more difficult to dry well. 95% of both the regrowth and the plantation timber fell in Class E quality for internal checking. Overall, along with the assessment that both regrowth and plantation timber was Class C quality for the variation of final moisture contents, these regrowth timber boards and the plantation timber boards fell in the lower quality classes for the criteria of checking and target moisture content for appearance products. Quality Classes A and B are higher quality categories, for appearance—grade products. The dispersion of the final moisture contents was greater with the plantation blackbutt timber (0.24 within; 0.36 between) than with the regrowth blackbutt timber (0.19 within; 0.15 between) for both within—tree and between—trees variability, respectively. In general, the diffusion coefficients for the timber in this thesis ranged between 1.14×10—10 and 6.77×10—10 m2s—1. There was a significant difference between the diffusion coefficients of the plantation and regrowth blackbutt timber for the within—tree test at a 0.05 significance level. The variation in the diffusion coefficients within a single plantation blackbutt log was higher than the variation in the diffusion coefficients within a regrowth blackbutt log. In addition, there was also a significant difference between the diffusion coefficients of regrowth and plantation blackbutt timber at a 0.05 significance level for between—trees variability. The initial moisture contents, the diffusion coefficient, and shrinkage decreased from pith to bark and the basic density and the modulus of elasticity (MOE) increased in the same direction, within a tree, for both regrowth and plantation blackbutt. The results of the analysis of variance (ANOVA) showed that radial and circumferential effects were significant sources of the within—tree variations for the diffusion coefficient, the initial moisture content, the basic density, the failure strain, the failure stress, the modulus of elasticity and shrinkage. A similar result was found for the ANOVA between trees. The ANOVA results also indicated that the smaller—sized samples used for the analysis (i.e. sub—samples of eight boards for the within—tree test of regrowth blackbutt, sub—samples of four boards for the between—trees test of regrowth blackbutt, sub—samples of six boards for the within—tree test of plantation blackbutt, and sub—samples of six boards for the between—trees test of plantation timber) were sufficient to measure the key effects adequately for the variabilities of the physical, transport, and mechanical properties, provided that all combinations of sub—samples were considered. There was no significant difference between the ANOVA results for these smaller sized samples (less than 1% change), considering all combinations, and the ANOVA results for the ‘full’ board cases. Though the sample sizes were unusually small to represent population statistics by most standards, all combinations of the sub-sets were assessed and an averaged picture of the situation with smaller sample sizes was given. Moreover, MOEs (both green and kiln—dried states) of plantation blackbutt were lower compared with the MOE of regrowth blackbutt. It is possible that the MOE was correlated with the basic density, and the basic density of regrowth blackbutt was higher than the basic density of plantation blackbutt. The shrinkage in the tangential direction was approximately twice the amount of radial shrinkage. The ranges of the measured radial shrinkage values were 0.024 – 0.094 mm mm-1 for regrowth blackbutt and 0.037 – 0.125 mm mm-1 for plantation blackbutt. The higher shrinkage values for plantation blackbutt timber show that plantation material is less stable dimensionally, and this situation is possibly due to the high juvenile wood content and low basic density. These differential (tangential:radial) shrinkage values ranged from 1.12 – 2.93 for regrowth blackbutt and 1.09 – 2.92 for plantation blackbutt. Tests were conducted to determine the degree of statistical normality for the distribution of each property (physical, transport, and mechanical). The results of the normality tests showed that most timber properties for regrowth and plantation blackbutt timber were distributed normally on a linear scale based on the W test, both within and between—trees. On the other hand, some timber properties showed a better fit with the three—parameter lognormal distribution, such as the diffusion coefficient and the green failure strain for within—tree variability of regrowth timber. The means and standard deviations of these distributions were further analysed by applying significance tests at a 0.05 level. For regrowth blackbutt, the data for the initial moisture content, the basic density, the diffusion coefficient, and shrinkage showed no significant differences, comparing the cases within and between—trees. The mechanical behaviour, however, was significantly different between each group and suggested that the two regrowth trees used for the within—tree test were stiffer than the 12 trees used for the between—trees test. It was possible that the mechanical properties were dependent on the geographic location where the tree was felled, and the heartwood content of each log. On the other hand, since all the plantation logs used for the within and between—trees tests were taken from one location, the mechanical properties were not significantly different within the plantation sample. The silviculture and the age of all the plantation trees were the same, which might have contributed to the small variation of the timber properties between the within—tree and between—trees cases for plantation material. Lastly, a significance test was conducted to compare the properties of regrowth and plantation blackbutt timber. Most timber properties (except for the initial moisture content) were significantly different between regrowth and plantation blackbutt. Plantation blackbutt timber had a lower basic density, higher diffusion coefficient and shrinkage, and the modulus of elasticity (both in its green and dried states) was lower compared with regrowth blackbutt timber. In addition to geographic location, heartwood/juvenile content, maturity (age), and differences in microfibril angle may have affected these timber properties in plantation blackbutt timber. For all the experiments, the possibility that there is a correlation between high initial moisture contents, higher diffusion coefficients, low basic densities, and low green modulus of elasticity’s (MOE) was assessed using principal components analysis (PCA). A principal components analysis was performed on the four parameters: the basic density, the initial moisture content, the diffusion coefficient, and the green MOE. The results of the PCA showed that the principal component for the within—tree and between—trees test accounted for 93% and 94% (for regrowth), and 92% and 90% (for plantation), respectively, of the total amount of variation within these parameters, giving some support for the mentioned correlation between the parameters. The strong correlation between the diffusion coefficient and the basic density, D; the diffusion coefficient and the initial moisture content, Xi; and the diffusion coefficient, D, and the modulus of elasticity, EG were represented by empirical equations. The F significance test was conducted to determine if the equations from the within—tree and between—trees tests, and the regrowth blackbutt and plantation blackbutt tests, were significantly different. The difference between the equations for the within—tree and between—trees variability of plantation blackbutt timber (Factual= 1.35  Fexpected= 2.13) was the only result that showed no significant difference. A possible reason for this finding is that the boards from the within—tree and between—tree variability tests, hence the trees, were all felled from one location. On the other hand, the other tests compared boards that were taken from trees felled from different locations, including the regrowth blackbutt within trees, compared with between trees. The results of the significance tests imply that boards taken from one location, whether they are within—tree and between—tree samples, have probably come from the same overall population. Hence using any of the correlations (within—tree or between—trees for plantation blackbutt) would be suitable to estimate the diffusion coefficient of other plantation blackbutt samples at the same location. Overall, these empirical equations can be used to estimate important drying properties of other regrowth and plantation blackbutt samples, such as the diffusion coefficient, using easily measured properties, like the initial moisture content or the basic density, as long as the boards are taken from the same age group (i.e. regrowth or plantation) and the same location. Thereafter, the blackbutt timber boards may be segregated based on the range of diffusion coefficients as estimated from the densities or the initial moisture contents. Hence a suitable drying schedule should be chosen for each segregated group. Collapse was not significant for blackbutt samples studied in this thesis, and possibly this timber species in general, but it may be significant for other eucalyptus species such as collapse—prone Eucalyptus regnans F. Muell (mountain ash) This potential limitation means that care is needed in applying the relationships found in this thesis to collapse—prone species. The same drying model was used to assess the effects of different drying schedules (i.e. increasing and decreasing the dry—bulb and wet—bulb temperatures of the original drying schedule by 5oC and 10oC) and of the potential correlations between the diffusion coefficient, the green MOE, the shrinkage coefficient (calculated from the tangential shrinkage), and the initial moisture content on the variability of final moisture contents, when the average moisture content within a stack of timber reached 15%. In addition, the maximum strain attained by the timber boards was also predicted. The results show that for regrowth blackbutt timber and accounting for within—tree variability, there was no relationship between the length of the drying schedule and the dispersion of final moisture contents. As the temperatures increased, the dispersion of the final moisture contents showed no consistent trend. The absence of a clear trend may be due to the different locations where the logs used for the within—tree test of regrowth variability were taken. On the other hand, the between—tree variability sensitivity tests for both regrowth and plantation blackbutt timber and the within—tree variability sensitivity test for plantation blackbutt timber show a relationship between the length of the drying schedule and the dispersion of final moisture contents. The dispersion of the final moisture contents decreased as temperatures increased. Generally, the ‘+10oC’ drying schedule gave the shortest time for the stack of timber to reach the target average moisture content, and its conditions produced the smallest dispersion of final moisture contents. It was also observed, however, for all sensitivity tests, that as the temperature of the drying schedule increased, the average predicted values decreased for the maximum strains reached. This is a very unusual result, because normally the strains and stresses would be expected to increase with increasing temperature. A possible reason for this is that within a piece of timber, as the temperatures increase, the diffusion coefficient will increase because the internal average temperature increases, so the internal resistance to mass transfer decreases, which leads to the moisture content gradient decreasing, even though the drying rate may slightly increase. This decreases both the drying time and the maximum strain reached as the temperature increases. There are limitations, however, associated when using high temperatures in kiln drying such as collapse and timber discolouration. The optimization technique created by Pordage (2006) was improved by using a large number of measurements to quantify the variability in the properties of blackbutt timber. The first simulation accounted for the between—tree variability of the biological parameters in regrowth blackbutt, and the second simulation accounted for both the within and between—tree variability of the timber properties in plantation blackbutt. Since location was observed as a main source of variability, the timber properties used for each simulation were taken from the logs that were felled from the same location. The mean and the standard deviations of the initial moisture content, the reference diffusion coefficient, and the shrinkage coefficient of regrowth and plantation blackbutt timber boards measured in the actual drying experiments, along with the covariance between these properties represented by a covariance matrix, were used for each simulation. The total drying time of the optimized drying schedule of plantation blackbutt timber was longer (an additional 168 hours, i.e. 472 hours) compared with the total drying time of the optimized drying schedule of regrowth blackbutt timber (304 hours). Due to the greater variability present in plantation blackbutt, slower drying is required. Moreover, the total drying times from the ‘regrowth blackbutt’ optimization and the ‘plantation blackbutt’ optimization (which both accounted for variability) were shorter compared with the total drying time of the original drying schedule for 28 mm—thick mixed—sawn blackbutt boards, i.e. 504 hours. On the other hand, the total drying times of the optimized drying schedules of regrowth and plantation blackbutt timber were greater than the total drying time (152 hours) predicted by Pordage’s (2006) optimized drying schedule accounting for the variability of Eucalyptus paniculata (grey ironbark). He had limited information on the variability of the parameters of grey ironbark and thus used an estimate from another eucalyptus species, Eucalyptus obliqua (messmate), whereas in this thesis, the variabilities for regrowth and plantation blackbutt used for the optimization technique were measured and part of the scope for this study. Overall, this is a typical application of the data obtained in this thesis to the optimization of drying schedules.

A study of the literacies used by two groups participating in Health Walks run by Blackburn with Darwen Council. In this study, I examine the literacy practices that took place during participation in group led walks organised by Blackburn with Darwen Borough Council as part of their Health Walks provision. My focus was on how participation in Health Walks effects changes in individuals. The study found its focus in anthropological participant observation with two groups of walkers. Data took the form of observational field notes, recordings of talk generated whilst walking and written accounts of walks completed by some participants. My analysis of the data included the arts based processes of creating trail maps and transcribing recorded talk onto Ordnance Survey maps. I used these processes as a heuristic to help draw out the properties of the literacies encountered and their relationship to place. The study is rooted in an understanding of literacy as an everyday activity that permeates people’s lives and through which power relationships are expressed and sustained. I foreground oral storytelling practices and term these practices mobile literacies. I examined how mobile literacies emerge in mobility and are shaped by the landscapes through which the walkers move. I aimed to demonstrate that participation in mobile literacies is a significant transformational aspect of the experience of participating in Health Walks. The study introduces the concept of mobile literacies as a discrete literacy practice. I characterise Mobile Literacies as emplaced, embodied collective storytelling practices that are generated by affectual response to moving through landscape. I describe how the practice offers opportunities to interrogate, extend and re – calibrate identities, express resistance and participate in collaborative acts of generation and transformation. The study offers policy makers and practitioners an alternative lens by which to view how walkers experience their involvement in Health Walks and new tools by which to measure impact and design further initiatives. In terms of education it offers a glimpse of the affordances of walking and the local environment in developing strategies by which to involve learners in meaningful and creative language and literacy learning.

This thesis reports laboratory and field investigations on the aspects of biology of the Stethorus vagans, an Australian ladybird that feeds on all stages of two-spotted mite, Tetranychus urticae. Aspects of the biology of S. vagans were studied in the laboratory at constant and fluctuating temperatures. They regularly fed on all stages of T. urticae and there was no significant difference in male and female longevity at different temperatures. For field studies potted French bean plants infested with T. urticae were exposed in the field. Adult S. vagans was found to consume a range of alternative prey if the primary host was not available, but only one of the alternative hosts had the potential to support reproduction. Time partitioning behaviour and prey consumption rates were assessed, and how S. vagans located their prey was investigated. S. vagans exhibited many of the attributes of an effective biological control agent such as high reproductive level, location of prey at low levels, reproduction at low densities, and ability to feed on alternative hosts. It is concluded that S. vagans has a number of characteristics likely make them useful as a natural enemy of T. urticae
Doctor of Philosophy (PhD)

This thesis reports laboratory and field investigations on the aspects of biology of the Stethorus vagans, an Australian ladybird that feeds on all stages of two-spotted mite, Tetranychus urticae. Aspects of the biology of S. vagans were studied in the laboratory at constant and fluctuating temperatures. They regularly fed on all stages of T. urticae and there was no significant difference in male and female longevity at different temperatures. For field studies potted French bean plants infested with T. urticae were exposed in the field. Adult S. vagans was found to consume a range of alternative prey if the primary host was not available, but only one of the alternative hosts had the potential to support reproduction. Time partitioning behaviour and prey consumption rates were assessed, and how S. vagans located their prey was investigated. S. vagans exhibited many of the attributes of an effective biological control agent such as high reproductive level, location of prey at low levels, reproduction at low densities, and ability to feed on alternative hosts. It is concluded that S. vagans has a number of characteristics likely make them useful as a natural enemy of T. urticae

A study of grey goral (Nemorhaedus goral) in the Margalla Hills National Park, Pakistan, was conducted to develop a management plan for this animal. Goral are listed as endangered in Pakistan and elsewhere. They are confined to the steep slopes and difficult terrain that cover 28 percent of the total park area. Another 21 percent of the park area has similar habitat, but currently no goral occur there. Forty to 60 animals are estimated to be living in the park. Groups of two to three animals are common. During observation, goral spent most of their time in feeding, moving, and surveillance . Juveniles spent less time in surveillance and more in resting and ruminating than the adults. Group size was inversely correlated with the time spent in surveillance. Goral foraged early in the morning and late in the evening and were rarely seen during the day. They changed their foraging activities from browsing during the winter to almost entirely grazing during the summer. The rutting period extended from October to December and the lambing period from March to May. Goral populations in the park were estimated to be increasing at a rate of 7 percent annually . They always escaped to a nearby ridge when danger was perceived. Adults and juveniles had dominant and subordinate interactions. In goral habitat, about 60 percent of the vegetation consists of plant species commonly eaten by the animals. These species include Themeda anathera, Chrysopogon aucheri, Carissa opaca, Acacia modesta, Mimosa rubicaulis, and Ipomoea hispida. Human and livestock populations differ significantly inside and outside goral habitat in the park. Lack of suitable habitat, predation, poaching, and human and livestock pressures affect the goral population and its range in the park. Reintroduction plans for blackbuck (Antilope cervicapra) and cheer pheasant (Catreus vallichii) were analyzed to determine the commonalities: source of animals, poaching, predation, and insufficient staff and funds. A goral management plan based on my field studies and the analysis of the other reintroduction plans are discussed. A general wildlife management strategy for Pakistan is discussed. The government should have a well-defined policy about wildlife and park management. Habitat remains the critical factor. Strong legislation, well-educated and well-equipped staff, and proper funding are required for this purpose. In addition, education and economic development of the public, especially those living in and around parks, are essential.

Agricultural systems are known to emit nitrous oxide (N2O)---a potent greenhouse gas. The roving flux tower measuring system of Agriculture and Agri-Food Canada was used to make continuous measurements of N2O fluxes in an edible pea field in Western Quebec in 2003-04 and then in an alfalfa-timothy forage field in Eastern Ontario in 2004-05. The experiment was designed to capture, at the field scale, the expected large N2O emissions occurring as a result of fertilizer application for a year, in relation to both large precipitation events and spring thaw.
Growing season N2O emissions averaged 0.5 to 5 mg N2 O-N m-2 d-1 with peaks following snow melt (between 5 and 8 mg N2O-N m-2 d-1) and manure applications (8 to 37 mg N2O-N m-2 d -1). Although generally small (<0.25 mg N2O-N m -2 d-1), emissions were detectable during the fall and winter, indicating the importance of including them in annual emission totals.
The measurements were used to verify the performance of the simulation model DNDC (DeNitrification-DeComposition) in estimating N2O emissions from legumes and in response to dairy manure application. Sensitivity tests were also carried out in which baseline input values were modified. Results suggest that the current model version (DNDC8.9) requires further modification prior to application for estimating greenhouse gas emissions in national accounting systems.

This thesis considers Kant's departure from moral naturalism. In doing so, it explores the relationship between ethics, naturalism, normativity and freedom. Throughout this exploration, I build the case that Kant's ethics of autonomy allows us to make better sense of ethics than Hume's moral naturalism. Hume believes that morality is ultimately grounded in human nature. Kant finds this understanding of ethics limiting. He insists that we are free - we can critically reflect upon our nature and (to an extent) alter it accordingly. This freedom, I contend, renders the moral naturalist's appeal to nature lacking. Of course, a Kantian conception of freedom - some form of independence from the causal order - is fairly unpopular in contemporary circles. In particular, a commitment to naturalism casts doubt on such a notion of freedom. I argue with Kant that such a conception of freedom is essential to the conception of ourselves as rational agents. The critical turn, unlike naturalism, warrants this conception of freedom, accommodating the point of view of our rational agency. It thus allows Kant's ethics of autonomy to better grasp certain key elements of morality - normativity and our agency - than Hume's moral naturalism.

Cette version de la thèse a été tronquée des certains éléments protégés par le droit d’auteur. Une version plus complète est disponible en ligne pour les membres de la communauté de l’Université de Montréal et peut aussi être consultée dans une des bibliothèques UdeM.
Si Norman McLaren (1914-1987) œuvre principalement dans le domaine onirique de l’animation, David Cronenberg (1943-), parfois surnommé « The Baron of Blood », réalise des films de fiction appartenant à un genre singulier qu’il a lui-même développé, celui de « l’horreur intérieure ». Que peuvent donc partager ces deux cinéastes aux univers a priori si distincts ? Chacun a construit une relation à long terme avec un compositeur : Maurice Blackburn (1914-1988) pour le premier, Howard Shore (1946-) pour le second. Mais si les univers des deux réalisateurs ont été maintes fois investigués, l’apport de leurs compositeurs respectifs demeure peu examiné. Or, d’un univers à l’autre, la musique semble jouer un rôle de toute première importance, chacun des compositeurs étant impliqué très tôt dans le processus cinématographique. Cette implication précoce dans la création collective est indicatrice de la place et du rôle centraux qu’occupent Blackburn et Shore et leur musique au sein de l’œuvre de McLaren, d’une part, et de Cronenberg, de l’autre. De la sorte, les partitions semblent ne pouvoir être considérées comme une simple illustration sonore des films, mais comme une composante tout à fait fondamentale, relançant dès lors la question du rôle de la musique au cinéma : comment le définir ? En outre, au fil de la rencontre continue sur plusieurs films, musique et cinéma en sont venus à un entrelacement tel qu’un style singulier de musicalisation des images se serait développé : quels sont les traits qui définissent ce style ? D’une collaboration à l’autre, cette thèse cherche à établir une poïétique de la création musico-filmique ; elle cherche à décrire et à comprendre les processus créateurs filmique et musical qui déterminent la composition d’une musique de film et, plus encore, une musicalité de tout le complexe audio-visuel. À travers des portraits examinant la pratique et le discours des créateurs et quatre analyses de bandes sonores (A Phantasy de Norman McLaren, Jour après jour de Clément Perron, Crash et A Dangerous Method de David Cronenberg), des liens se tissent peu à peu entre les pensées et les pratiques des deux compositeurs qui développent des stratégies similaires et originales face aux problèmes que leur posent les œuvres de McLaren (l’indissociabilité de la musique et de l’image) et de Cronenberg (la « transformation de l’esthétique humaine »). D’un binôme à l’autre, le cinéma se transforme en un laboratoire musico-filmique où chacun élabore une « méthode dangereuse » qui force l’analyste à explorer de nouvelles avenues méthodologiques.
Norman McLaren’s (1914-1987) animation work evokes a primarily dream-like world. David Cronenberg (1943-), also sometimes known as the “Baron of Blood,” makes fiction films that belong to a singular genre he developed: the “inner horror.” So what can these two filmmakers possibly have in common? They both built a long-term relationship with composers: Maurice Blackburn (1914-1988) for the former and Howard Shore (1946-) for the latter. Though the distinct approaches of these two directors have been widely studied, the weight of the contributions of their respective composers remains largely unmeasured. And this, despite the fact that music seems to play a primary role in these two directors’ process since, in each instance, the composer is involved very early on. This unusually early involvement of the composer, and the ongoing collaboration it entails, are indicative of the central place and role held by Blackburn and Shore’s music in McLaren’s work on the one hand, and Cronenberg’s on the other. This considered, their scores must no longer be seen as direct sound illustration of the films, but rather as essential components of the films, even though such a stance forces us to rethink how we define the role of music in film. Furthermore, from film to film, music and cinema become so intertwined that a singular style of musicalization of the image develops, begging the question: what are the characteristics of this style? From one collaboration to the other, this thesis seeks to establish a poietic of film-music creation; it looks to describe the cinematic and musical creative processes that determine the composition of film music and, beyond that, the musicality of the entire audio-visual complex. Through portraits that investigate the practice and discourse of creators and through the analysis of four soundtracks (A Phantasy by Norman McLaren, Day After Day by Clément Perron, Crash and A Dangerous Method by David Cronenberg), the thoughts and practices of the two composers, who develop similar innovative strategies to solve the problems posed by the works of McLaren (the inseparability of music and image) and Cronenberg (the “transformation of human aesthetics”), are gradually connected. From one duo to another, cinema becomes a musical and cinematic laboratory where each develops a “dangerous method” which forces the analyst to explore new methodological avenues.

This work examines the relationship between moral philosophy and literature. I start by exploring a dialectic that exists between “prevalent view” theorists (i.e., D. D. Raphael and Onora O'Neill), who argue that the moral interest of literature lies in explicit deliberative arguments modeled in literary texts, and Diamondian realist theorists (i.e., Alice Crary, Cora Diamond and Iris Murdoch), who argue that the “prevalent view” is too narrow. Rather, the ways in which literature affects us emotionally can make ineliminable contributions to fully rational moral thought. In Chapter Two, I explore potential challenges to this position, drawn from the works of Simon Blackburn. He argues that there are epistemological concerns (it relies upon a faulty view of language), and moral concerns (specifically relativism) with Diamondian realism. I respond to these challenges in Chapter Three and conclude that Crary, Diamond, and Murdoch have given us a better picture of literature's moral value.

Shaped in part by diverse landscapes, game profiles, and ruling personalities, hunting in the Indian princely states in the colonial period was heterogeneous to a previously unrecognized extent. At the same time, significant underlying political, social, and cultural continuities unified states and their rulers’ approaches to sport. Focusing on the Rajput realms of Mewar, Orchha, and Bikaner, I show how princes of different ranks negotiated their states’ divergent landscapes in pursuit of dissimilar game, and how they trusted in superior hunting grounds, wildlife, and shooting methods to advance their personal standings and sovereign powers. I also investigate how these rulers used hunting to maintain connections with their state and lineage histories, to exemplify local Rajput ideals and identities, and to manage relationships with various audiences, including their subjects, state nobles, other princes, and British officials. This study is concerned as much with princely perceptions of game and shooting grounds as with “real” landscapes or environmental changes. I examine how the princes conceptually linked natural abundance with favorable political conditions and degradation with lost power and compromised dignity. I consider what it meant to pursue tigers, wildfowl, antelope, and wild boar in dense jungles, wetlands, arid plains, and imposing hills. In addition, I look at the ways princes attempted to employ and also to modify those meanings to suit their own purposes. I did the research for this dissertation at government and private archives in India and the United Kingdom. Because my primary goal was to discover princely views, I relied as far as possible on sources produced by elite Indians or by those in their service. Among the materials I used were state government records, personal correspondence, speeches, game diaries, hunting memoirs, photographs, and miniature paintings. Much of the documentation was in English, with the major exception of records relating to Mewar State and its subordinate noble estates. The language of those papers ranged from Hindi through Rajasthani (Mewari). To understand British responses better, I consulted Government of India records. Published memoirs and travelogues written by Europeans who visited and hunted in the regions under consideration also proved useful.
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Indiana University-Purdue University Indianapolis (IUPUI)
This thesis analyzes the relationship between Flanner House, an African American settlement house, and Planned Parenthood of Central Indiana to determine why Flanner House director Cleo Blackburn would not allow a birth control clinic to be established at the Herman G. Morgan Health Center in 1951. Juxtaposing the scholarship of African Americans and birth control with the historiography of black settlement houses leads to the conclusion that Blackburn’s refusal to add birth control to the health center’s services had little to do with the black Indianapolis community’s opinions on birth control; instead, Flanner House was confined by conservative limitations imposed on it by white funders and organizations. The thesis examines the success of Blackburn and Freeman B. Ransom, Indianapolis’s powerful black leaders, in working within the system of limitations to establish the Morgan Health Center in 1947. Ransom and Blackburn received monetary support from the United Fund, the Indianapolis Foundation, and the U.S. Children’s Bureau, which stationed one of its physicians, Walter H. Maddux, in Indianapolis. The Center also worked as a part of the Indianapolis City Board of Health’s public health program. These organizations and individuals did not support birth control at this time and would greatly influence Blackburn’s decision about providing contraceptives. In 1951, Planned Parenthood approached Blackburn about adding birth control to the services at Morgan Health Center. Blackburn refused, citing the Catholic influence on the Flanner House board. While acknowledging the anti-birth control stance of Indianapolis Catholics, the thesis focuses on other factors that contributed to Blackburn’s decision and argues that the position of Flanner House as a black organization funded by conservative white organizations had more impact than any religious sentiment; birth control would have been a liability for the Morgan Health Center as adding contraceptives could have threatened the funding the Center needed in order to serve the African American community. Finally, the position of Planned Parenthood and Flanner House as subordinate organizations operating within the limitations of Indianapolis society are compared and found to be similar.