It was the purpose of the investigation to determine the effects of selected high intensity monochromatic radiations on the growth of pith callus tissue of Pelargonium zonale, variety Enchantress Fiat. In addition, the extent of cell differentiation was to be determined for tissues grown under each experimental treatment.

Wood cutting properties for the chains of chainsaw is measured in the lab by analyzing the force, torque, consumed power and other aspects of the chain as it cuts through the wood log. One of the essential properties of the chains is the cutting efficiency which is the measured cutting surface per the power used for cutting per the time unit. These data are not available beforehand and therefore, cutting efficiency cannot be measured before performing the cut. Cutting efficiency is related to the relativehardness of the wood which means that it is affected by the existence of knots (hardstructure areas) and cracks (no material areas). The actual situation is that all the cuts with knots and cracks are eliminated and just the clean cuts are used, therefore estimating the relative wood hardness by identifying the knots and cracks beforehand can significantly help to automate the process of testing the chain properties, saving time and material and give a better understanding of cutting wood logs to improve chains quality.Many studies have been done to develop methods to analyze and measure different features of an end face. This thesis work is carried out to evaluate a machinelearning model to detect knots and cracks on end faces and to understand their impact on the average cutting efficiency. Mask R-CNN is widely used for instance segmentation and in this thesis work, Mask R-CNN is evaluated to detect and segment knots and cracks on an end face. Methods are also developed to estimatepith’s vertical position from the wood image and generate average cutting efficiency graph based on knot’s and crack’s percentage at each vertical position of wood image.

A thermo-chemical treatment method was used to produce biogenic amorphous silica from South African sugarcane and maize residues. Different fractions of South African sugarcane (leaves, pith, and fiber) were processed for silica production. The biomass samples were leached with either 7 wt% citric acid or 7 wt% sulfuric acid at 353 K for 2 h prior to being rinsed, dried and combusted using a four-step program ranging from room temperature to 873 K in a furnace. The characterization of the pre-treated biomass samples was conducted using thermogravimetric analysis (TG/DTA), X-ray fluorescence analysis (XRF) and elemental analysis (CHN), while the final products were characterized by XRF, X-ray diffraction (XRD), elemental analysis, nitrogen physisorption and scanning electron microscopy (SEM). Citric acid pre-treatment proved to be an attractive alternative to mineral acids. Amorphous biogenic silica was produced from sugarcane leaves in good quality (0.1 wt% residual carbon and up to 99.3 wt% silica content). The produced biogenic silica also had great textural properties such as a surface area of up to 323 m2 g−1, average pore diameter of 5.0 nm, and a pore volume of 0.41 cm3 g−1.

Tracking of tree logs from a harvesting site to its processing site is a legal requirement for timber-based industries. Wood log identification is an important task in the forestry industry and has traditionally relied on manual inspection by trained experts. However, with the increasing demand for wood products and the need for efficient and accurate identification, there has been a growing interest in developing automated wood log identification systems. In this study, we explored approaches to wood log identification with three objectives: automated log identification, damaged log identification (detection of damaged log), and pith detection (estimation of the pith location). We propose a novel approach for wood log identification using computer vision techniques. Our approach involves capturing images of wood logs using a digital camera, detection of pith location using machine learning model, then applying image processing algorithms to extract relevant features, such as the bark pattern, rings, and use information provided by radial line that extends from the bark to the pith to identify the wood log. In our experiments, we used different image processing techniques to build computer vision models for log identification, trained machine learning and deep learning models to classify the wood log into damaged or not, and deep learning models for estimation of the pith location. The findings of this study indicate that the proposed approach for wood log identification work best with Canny Edge Detection technique, and we can further extend this approach.

No description available.

<p>This report describes an annual line detection algorithm for the WoodEye quality control system. The goal with the algorithm is to find the positions of annual lines on the four surfaces of a board. The purpose is to use this result to find the inner annual ring structure of the board. The work was done using image processing techniques to analyze images collected with WoodEye. The report gives the reader an insight in the requirements of quality control systems in the woodworking industry and the benefits of automated quality control versus manual inspection. The appearance and formation of annual lines are explained on a detailed level to provide insight on how the problem should be approached. A comparison between annual rings and fingerprints are made to see if ideas from this area of pattern recognition can be adapted to annual line detection. This comparison together with a study of existing methods led to the implementation of a fingerprint enhancement method. This method became a central part of the annual line detection algorithm. The annual line detection algorithm consists of two main steps; enhancing the edges of the annual rings, and tracking along the edges to form lines. Different solutions for components of the algorithm were tested to compare performance. The final algorithm was tested with different input images to find if the annual line detection algorithm works best with images from a grayscale or an RGB camera.</p>

The study covered the period August 1971 to February 1975 and was conducted in three blackcurrant plots. One plot comprised mature bushes that were pruned but not sprayed during the course of the study; the other two plots were subject to full normal managerial practices including spraying. Information on various aspects of the biology was revealed and this clarified some of the areas about which little was known previously especially for the Southern Hemisphere. Fecundity is 100 eggs per female, fertility in the field is at least 97% and predation of eggs is always less than 5%. There are six larval instars. Fungi of the genera Beauveria and Cordyceps cause up to 10% mortality of the larvae. This is the first record of the latter genus infecting S. tipuliformis. A sampling plan was developed to enable estimates of the population of S. tipuliformis at various stages to be obtained. This gave information on the distribution of stages of the life cycle within the canes according to the age of the wood. These samples also permitted the construction of life tables for three generations of S. tipuliformis in one plot and one generation in the others. Replication both in space and time was therefore achieved and the results were further replicated by considering each plot as nine separate blocks. The dispersion of the egg and larval stages was tested and found to fit the negative binomial model. A common k, kc, was calculated for the egg stage and the larval c stage. Though not vital to this present study various transformations of the raw data were investigated to see which were most appropriate in order to stabilise the variance for analyses in which such suitability is vital. The logarithmic transformation based on the k parameter of the k negative model [log (x + k/2)) was the most successful. The mortality of the eggs was quite low but a significant proportion of the emerging larvae fail to colonise the pith of a cane. This mortality is density dependent. Other mortalities including winter pruning are density independent or random. The key stage of the life cycle revealed by the life tables is the adult survival. This survival and the consequent population trend index determined from the number of eggs laid was found to be affected by the prevailing weather during the flight period especially during the last week of November and the first two weeks of December.

This report describes an annual line detection algorithm for the WoodEye quality control system. The goal with the algorithm is to find the positions of annual lines on the four surfaces of a board. The purpose is to use this result to find the inner annual ring structure of the board. The work was done using image processing techniques to analyze images collected with WoodEye. The report gives the reader an insight in the requirements of quality control systems in the woodworking industry and the benefits of automated quality control versus manual inspection. The appearance and formation of annual lines are explained on a detailed level to provide insight on how the problem should be approached. A comparison between annual rings and fingerprints are made to see if ideas from this area of pattern recognition can be adapted to annual line detection. This comparison together with a study of existing methods led to the implementation of a fingerprint enhancement method. This method became a central part of the annual line detection algorithm. The annual line detection algorithm consists of two main steps; enhancing the edges of the annual rings, and tracking along the edges to form lines. Different solutions for components of the algorithm were tested to compare performance. The final algorithm was tested with different input images to find if the annual line detection algorithm works best with images from a grayscale or an RGB camera.

This dissertation is a historical evaluation of the movement of the English courts from the doctrine of pith and marrow to the Catnic test in the determination of non-textual infringement of patents. It considers how and why the doctrine was replaced with the Catnic test. It concludes that this movement occurred as a result of the adoption by a group of judges of literalism in the construction of patents while another group dissented and maintained the correct application of the doctrine. Although the Court of Appeal and the House of Lords initially approved the literalist approach, they, after realising its untennability, adopted the dissenters’ approach, but, ultimately, adopted the Catnic test in which features of the dissenters’ approach were included. The dissertation concludes that the doctrine of pith and marrow, correctly applied, should have been retained as the Catnic test creates uncertainty and confusion. / Mercantile Law / LL.M.

This dissertation is a historical evaluation of the movement of the English courts from the doctrine of pith and marrow to the Catnic test in the determination of non-textual infringement of patents. It considers how and why the doctrine was replaced with the Catnic test. It concludes that this movement occurred as a result of the adoption by a group of judges of literalism in the construction of patents while another group dissented and maintained the correct application of the doctrine. Although the Court of Appeal and the House of Lords initially approved the literalist approach, they, after realising its untennability, adopted the dissenters’ approach, but, ultimately, adopted the Catnic test in which features of the dissenters’ approach were included. The dissertation concludes that the doctrine of pith and marrow, correctly applied, should have been retained as the Catnic test creates uncertainty and confusion. / Mercantile Law / LL. M.