Mechanical strength in wood has always been compromised due to the complex behaviours of the material when interfered with moisture and heat. These factors has always limited the use of the material. However, the will of using more sustainable materials such as wood has contributed to a wider use of the material and several new ways that lead to improvement. Several of these methods emphasizes the joining of two wood components together endwise, where finger-joints are the most commonly used method. Several studies regarding how well finger-joints can withstand external load has been made over the years. However, many of these studies focuses on geometrical properties or strength varying in different species. This study focuses on how relative humidity and temperature affects mechanical strength in finger-jointed wood products. There were beliefs before the research started that increasing temperature would affect mechanical strength greatly. However, it turned out to only affect the mechanical strength marginally, and that relative humidity was the largest contributor to decreasing tolerance levels. It is important to notify that mechanical strength seemed to be directly affected to moisture content (MC), which is a result of an interactive relationship with both temperature and RH. It was particularly MC-levels above 9.2% that showed a decrease in mechanical strength. This research also focused on estimating the relative MOR per cross-section in varying conditions. This method could be used to better understand to which degree hygroscopic factors affects mechanical strength relative to the glued-surface area between finger-joints. Even though the findings in this study indicates that there seems to be possible to estimate strength in regards to relative MOR per cross-section, the results were not sufficient to be viewed as scientifically proof. The findings could however be used as ground for future studies.

Orientador: Maurílio Boaventura / Banca: Evanivaldo Castro Silva Junior / Banca: Aparecido Nilceu Marana / Resumo: O objetivo deste trabalho é abordar o campo de orientação de impressões digitais, técnicas para sua extração e algumas de suas aplicações na área de processamento de imagens de impressões digitais. Almejando diminuir a interferência humana no processo de regularização do campo de oreintação foi, também, proposto um método para detecção da área da impressão digital, de forma automática no caso de imagens com boa qualidade e semi-automática no caso de imagens latentes, baseado em contronos ativos. Os testes realizadoscomprovam a eficácia das técnicas propostas / Abstract: The aim of this study is to discuss the orientation field of fingerprints, techniques for extraction and some of its applications in fingerprint image processing. Aiming to reduce human interference in the process of regularization of the orientation field was also proposed a method for fingerprint area detection, automatic in the case of good quality images and semi-automatic in the case of latent images, which was based on active contours. The computational tests showed the effectiveness of proposed techniques / Mestre

Finger flutings are lines and markings drawn with the human hand in soft cave sediment in caves and rock shelters throughout southern Australia, New Guinea and southwestern Europe, dating back to the Late Pleistocene. Analysis of these markings can reveal characteristics of the creators, such as age, sex and group sizes. However, despite a comprehensive method of study, data collection is still reliant on in field measurements and is often constrained by physical challenges within the caves. Advances in technology allow us to record archaeological data in three dimensions. Creating 3D models of finger fluting panels would allow for off-site measurements and other forms of detailed analysis. In this thesis, I test three different 3D scanning techniques, photogrammetry, tripod structured light scanning, and handheld structured light scanning, to determine the most appropriate method for the documentation of finger flutings based on factors such as portability, cost, efficiency, accuracy, as well as other challenges present in cave and rock shelter settings. I created replica fluting panels in three different media and created 3D models of them. I then compared measurements taken from the panels in person to measurements taken from the 3D-scanned models to see if there is statistically significant difference between the models and the panel. The results of my experiment show that 3D models of finger fluting panels are accurate representations of the experimental panels and that photogrammetry is the technique that best meets the requirements of finger fluting research. / Graduate

Vários estudos têm investigado a redundância cinética dos dedos da mão por meio da análise da interdependência e interação sinérgica entre os dedos da mão durante a produção de força máxima dos dedos e controle de força dos multiplos-dedos. No entanto, pouco se sabe sobre como as mudanças no comprimento muscular dos dedos da mão poderia afetar a produção de torque máximo, assim como a interação sinérgica entre os dedos da mão. Este estudo variou o ângulo da articulação metacarpofalangeana para investigar os efeitos do comprimento muscular sobre: a) produção de torque máximo dos dedos; b) dependência dos dedos; e, c) interação de torque dos dedos. Onze adultos jovens (23,09 ± 2,63 anos) foram convidados a produzir torque isométrico máximo em flexão, com o dedo individualmente em um período de 3-s. O torque do dedo instruído e dedos não instruídos foram registrados em sete diferentes posições da articulação metacarpofalangeana (-15 °, 0 °, 15 °, 30 °, 45 °, 60 ° e 75 °). Os participantes também foram convidados a produzir torque isométrico constante, com o dedo individualmente (I, M, A e Mn) durante 12 segundos. Os resultados mostraram que a alteração no comprimento muscular proporciona efeito na capacidade dos dedos de produzir torque independente. Maior independência dos dedos (ou seja, diminuição do torque enslaving) foi encontrada em menores comprimentos musculares. Nenhum efeito do comprimento muscular foi encontrado para a tarefa de controle de torque isométrico constante. / Several studies have investigated kinetic redundancy of the hand by examining finger dependency and the synergic interactions among the hand fingers during maximum finger force production and multi-fingers force/torque control. However, little is known about how changes in the fingers' muscle length would affect the maximum torque production as well as the synergic interaction among the fingers of the hand. This study manipulated the angle of the metacarpophalangeal joint in order to investigate the effects of muscle length on: a) maximum finger torque production; b) finger dependency; and, c) finger torque interactions. Eleven young adults (23.09 ± 2.63 years) were asked to produce maximum flexion isometric torque with one finger at a time over a 3-s period. The torque of both the instructed finger and non-instructed fingers were recorded over seven different metacarpophalangeal joints positions (-15°, 0°, 15°, 30 °, 45°, 60° and 75°). Participants were also asked to produce a constant isometric torque with one finger at a time (I, M, R e L) over 12 seconds. The results showed that changes in muscle length impacted the fingers' ability to produce torque independently. Higher finger independency (i.e., decreased torque enslaving) was found for the decreased muscle lengths. No effect of muscle length was found for the constant isometric torque control task.

Losing a hand is a highly traumatic experience affecting both the physical life and mental wellbeing of a person. It is therefore vital to provide a prosthetic hand with similar functionality to the hand lost. The human hand is a very delicate and complex part of the body used every day in a wide range of tasks from performing heavier works to smaller gestures. Due to all factors playing arole in how amputees live their lives, recreating a human hand is a very demanding and challenging task. As many as 30% of amputees experience depression and/or anxiety as a result of not having the same capabilities and opportunities as before the amputation. Amputation may be carried out both due to sudden accidents and as a result of congenital defiances and vascular illnesses. Since advanced prosthetic hands often come in at a price too high to reach a large part of the amputee consumer base, the case is often that only the richest amputees are able to afford electric prosthetic devices, and are thus often limited to simpler, body-powered alternatives. These alternatives are often found to be lacking in features and resemblance when comparing to the more technologically advanced electric prosthetics. A set of product development tools and methods were selected for the development process to ensure an organized approach for the project. The project was concluded with a finished and fully-manufacturable prosthetic hand with some advantages compared to the current market products. The hand developed in the project, named OYMotion hand 1.0 proved to have a number of advantages over competing products in selected functional areas such as force, finger speed and weight. The final market price of the product could not be estimated due to the fact that there are too many unknown factors involved to determine a final market price on the hand. The production cost is, however estimated to be significantly lower than the measured competing prosthetic hands. A deepened understanding about prosthetic hand design and development was obtained by studying the market, EMG, machine learning applications, hardware, gears, finger mechanisms,and materials.  By balancing concepts between cost, functionality and aesthetics, a structured reasoning couldbe used to prioritize certain aspects of the developing of the hand.The completed hand fulfills the required specifications and functions after undergoing anumber of analyses conducted in order verify material strength and mechanism functionality.Further grip strength analyses and calculations were excluded from the study due to the limitedavailable time given.

Vários estudos têm investigado a redundância cinética dos dedos da mão por meio da análise da interdependência e interação sinérgica entre os dedos da mão durante a produção de força máxima dos dedos e controle de força dos multiplos-dedos. No entanto, pouco se sabe sobre como as mudanças no comprimento muscular dos dedos da mão poderia afetar a produção de torque máximo, assim como a interação sinérgica entre os dedos da mão. Este estudo variou o ângulo da articulação metacarpofalangeana para investigar os efeitos do comprimento muscular sobre: a) produção de torque máximo dos dedos; b) dependência dos dedos; e, c) interação de torque dos dedos. Onze adultos jovens (23,09 ± 2,63 anos) foram convidados a produzir torque isométrico máximo em flexão, com o dedo individualmente em um período de 3-s. O torque do dedo instruído e dedos não instruídos foram registrados em sete diferentes posições da articulação metacarpofalangeana (-15 °, 0 °, 15 °, 30 °, 45 °, 60 ° e 75 °). Os participantes também foram convidados a produzir torque isométrico constante, com o dedo individualmente (I, M, A e Mn) durante 12 segundos. Os resultados mostraram que a alteração no comprimento muscular proporciona efeito na capacidade dos dedos de produzir torque independente. Maior independência dos dedos (ou seja, diminuição do torque enslaving) foi encontrada em menores comprimentos musculares. Nenhum efeito do comprimento muscular foi encontrado para a tarefa de controle de torque isométrico constante. / Several studies have investigated kinetic redundancy of the hand by examining finger dependency and the synergic interactions among the hand fingers during maximum finger force production and multi-fingers force/torque control. However, little is known about how changes in the fingers' muscle length would affect the maximum torque production as well as the synergic interaction among the fingers of the hand. This study manipulated the angle of the metacarpophalangeal joint in order to investigate the effects of muscle length on: a) maximum finger torque production; b) finger dependency; and, c) finger torque interactions. Eleven young adults (23.09 ± 2.63 years) were asked to produce maximum flexion isometric torque with one finger at a time over a 3-s period. The torque of both the instructed finger and non-instructed fingers were recorded over seven different metacarpophalangeal joints positions (-15°, 0°, 15°, 30 °, 45°, 60° and 75°). Participants were also asked to produce a constant isometric torque with one finger at a time (I, M, R e L) over 12 seconds. The results showed that changes in muscle length impacted the fingers' ability to produce torque independently. Higher finger independency (i.e., decreased torque enslaving) was found for the decreased muscle lengths. No effect of muscle length was found for the constant isometric torque control task.

abstract: Dexterous manipulation is a representative task that involves sensorimotor integration underlying a fine control of movements. Over the past 30 years, research has provided significant insight, including the control mechanisms of force coordination during manipulation tasks. Successful dexterous manipulation is thought to rely on the ability to integrate the sense of digit position with motor commands responsible for generating digit forces and placement. However, the mechanisms underlying the phenomenon of digit position-force coordination are not well understood. This dissertation addresses this question through three experiments that are based on psychophysics and object lifting tasks. It was found in psychophysics tasks that sensed relative digit position was accurately reproduced when sensorimotor transformations occurred with larger vertical fingertip separations, within the same hand, and at the same hand posture. The results from a follow-up experiment conducted in the same digit position-matching task while generating forces in different directions reveal a biased relative digit position toward the direction of force production. Specifically, subjects reproduced the thumb CoP higher than the index finger CoP when vertical digit forces were directed upward and downward, respectively, and vice versa. It was also found in lifting tasks that the ability to discriminate the relative digit position prior to lifting an object and modulate digit forces to minimize object roll as a function of digit position are robust regardless of whether motor commands for positioning the digits on the object are involved. These results indicate that the erroneous sensorimotor transformations of relative digit position reported here must be compensated during dexterous manipulation by other mechanisms, e.g., visual feedback of fingertip position. Furthermore, predicted sensory consequences derived from the efference copy of voluntary motor commands to generate vertical digit forces may override haptic sensory feedback for the estimation of relative digit position. Lastly, the sensorimotor transformations from haptic feedback to digit force modulation to position appear to be facilitated by motor commands for active digit placement in manipulation. / Dissertation/Thesis / Doctoral Dissertation Kinesiology 2014

Vários estudos têm investigado a redundância cinética dos dedos da mão por meio da análise da interdependência e interação sinérgica entre os dedos da mão durante a produção de força máxima dos dedos e controle de força dos multiplos-dedos. No entanto, pouco se sabe sobre como as mudanças no comprimento muscular dos dedos da mão poderia afetar a produção de torque máximo, assim como a interação sinérgica entre os dedos da mão. Este estudo variou o ângulo da articulação metacarpofalangeana para investigar os efeitos do comprimento muscular sobre: a) produção de torque máximo dos dedos; b) dependência dos dedos; e, c) interação de torque dos dedos. Onze adultos jovens (23,09 ± 2,63 anos) foram convidados a produzir torque isométrico máximo em flexão, com o dedo individualmente em um período de 3-s. O torque do dedo instruído e dedos não instruídos foram registrados em sete diferentes posições da articulação metacarpofalangeana (-15 °, 0 °, 15 °, 30 °, 45 °, 60 ° e 75 °). Os participantes também foram convidados a produzir torque isométrico constante, com o dedo individualmente (I, M, A e Mn) durante 12 segundos. Os resultados mostraram que a alteração no comprimento muscular proporciona efeito na capacidade dos dedos de produzir torque independente. Maior independência dos dedos (ou seja, diminuição do torque enslaving) foi encontrada em menores comprimentos musculares. Nenhum efeito do comprimento muscular foi encontrado para a tarefa de controle de torque isométrico constante. / Several studies have investigated kinetic redundancy of the hand by examining finger dependency and the synergic interactions among the hand fingers during maximum finger force production and multi-fingers force/torque control. However, little is known about how changes in the fingers' muscle length would affect the maximum torque production as well as the synergic interaction among the fingers of the hand. This study manipulated the angle of the metacarpophalangeal joint in order to investigate the effects of muscle length on: a) maximum finger torque production; b) finger dependency; and, c) finger torque interactions. Eleven young adults (23.09 ± 2.63 years) were asked to produce maximum flexion isometric torque with one finger at a time over a 3-s period. The torque of both the instructed finger and non-instructed fingers were recorded over seven different metacarpophalangeal joints positions (-15°, 0°, 15°, 30 °, 45°, 60° and 75°). Participants were also asked to produce a constant isometric torque with one finger at a time (I, M, R e L) over 12 seconds. The results showed that changes in muscle length impacted the fingers' ability to produce torque independently. Higher finger independency (i.e., decreased torque enslaving) was found for the decreased muscle lengths. No effect of muscle length was found for the constant isometric torque control task.

I denna litteraturstudie var syftet att undersöka hur användning av fingrar kan skapa möjligheter och/ eller begränsningar för elever i deras matematiska utveckling, främst i aritmetik. Studien tog utgångspunkt i vilka strategier elever använder vid användning av fingrar som hjälpmedel, där fokus låg på finger gnosis, fingerräkning, chisanbop och fingertal.  Vid insamling av data användes databaserna ERIC och UniSearch samt manuell sökning. Resultaten av insamlad data visade att användning av fingrar som hjälpmedel i matematiken kan innebära både begräsningar och möjligheter för elevernas matematiska utveckling i de tidiga skolåren. Resultaten visade också att fingrarna är mindre effektivt som hjälpmedel för elever i högre årskurser.

Phenolics in finger millet (FM) grain, including tannins, may impact significantly on its antimicrobial properties, functionality and health-promoting potential. Unfortunately, the location of tannins in the grain is unknown and there is limited information on the influence of variety on grain phenolic composition and antioxidant activity (AA). The effect of phenolics in FM grain on its malt fungal load and on the functional quality of its food products, including baked goods, is barely known. Twenty two FM grain types of varied visual kernel colour were analysed to determine the influence of grain type on phenolic composition, AA, and tannin localisation in the grain. Condensed tannins, anthocyanins and flavan-4-ols were detected. Light coloured grain types had no tannins and had much lower total phenolics (TP) relative to the pigmented types, and types that stained black with the Bleach test had much higher tannin content and much higher AA. The grains that stained black with the Bleach test and had high tannin content (0.60 to 2.08 mg catechin eqivalents/100 mg, db) had a dark coloured testa layer, indicating that the tannins were located in that layer. The results indicate that occurrence of tannins in FM is a varietal property and the tannins are predominantly responsible for the AA of the grain. Germinative energy (GE), enzymic activity, and total fungal count [TFC], and infection levels of 12 FM grain types of varied phenolic content were measured to determine the impact of phenolics in FM grain on its malt quality. The malt quality of high-phenol FM types was much higher than that of the low-phenol types, with respect to enzymic activity. TFC was negatively correlated with grain total phenolics (TP) and amount of phenolic type (APT) and there were some negative correlations between fungal species infection levels and TP and APT (p<0.05). GE and enzymic activity were positively correlated with TP and APT (p<0.05) and negatively correlated with TFC (p<0.01). The data indicate that phenolics in FM grain impact positively on its malt quality by contributing to its antifungal activity. Cookies in which wheat cake flour was substituted with 15, 35 and 55% (w/w) of either a non-tannin or a high-tannin FM flour were analysed to assess the impact of FM phenolics on cookie quality and AA (health-promoting potential). FM-substituted cookies, particularly those with high levels of the high-tannin FM, were inferior to cake flour cookies (control), with respect to spread, texture and integrity and their dark colour decreased their acceptance by a consumer panel. However, the acceptability of cookies containing up to 35% of either FM type was similar to that of control cookies. Cookies containing the high-tannin FM had antioxidant activities that were similar to or higher than the antioxidant activities of several plant products on the market. Thus, potentially health-promoting cookies can be made by substituting up to approximately 35% wheat with a high-tannin FM. The study indicates that high-phenol FM grain types have good malt quality, which is partly due to the antifungal activity of their phenolics. Although FM phenolics, particularly tannins, seem to affect cookie quality negatively, they contribute significantly to their health-promoting potential. / Thesis (PhD)--University of Pretoria, 2009. / Food Science / unrestricted