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An investigation into the effects of childhood atopic eczema on parental stressGillespie, G. N. January 1996 (has links)
Very little research has examined stress among parents of children with atopic eczema, though stressful events arc widely Implicated In Its actiology. This study Investigated reported stress among 38 parents of children with atopic eczema who had received hospital out-paticnt trcatmcnt within the previous 12 months. Responses of parents on the Parenting Stress Index were compared with published norms. Significantly elevated levels of stress among the study sample were found on the Difficult Child subscale. Total stress scores showed significant positive correlations with parental reports of illness severity. The majority of parents reported problems In relation to the symptom of scratching by their child with eczema. Recent problems with scratching were also found to correlate significantly with parenting stress. A rating scale was developed to allow parents to report on situational variables they associate with increased scratching by their child with eczema. The scale was found to have good test-retest reliability over a oneto-four week period. Three of its subscales (Environmental Sensitivity, Psychological Sensitivity and Negative Coping ) showed acceptable internal consistency. A fourth subscale (Positive Coping) showed poor internal consistency. Ratings on the Negative Coping subscale correlated significantly with parenting stress. A near-significant positive correlation was also found between parenting stress and the Psychological Sensitivity subscale. The methodological limitations of the study are discussed and implications for clinical practice and future research are outlined. The thesis also includes three small-scale research projects completetd during placements In Adult Mental Health, Learning Disabilities and Child and Adolescent services.
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Självskadebeteende : en studie om sex professionellas syn på fenomenetAndersson, Helen, Ohlin, Annika January 2006 (has links)
<p>The purpose of this study was trying to understand and explain why young people with psychological problems injure themselves by cutting, scratching and burning. The study also examine if self- injuring behaviour is an increasing problem in our society. Self-injuring behaviour is a phenomenon with dissimilar definitions. There are as many ways of injuring yourself as there are individuals who injure themselves. In this study six professionals, who through their work have contact with self- injuring people, have been interviewed. Their own view of self- injuring behaviour was put in comparison with the literature. It was found that despite their dissimilar educations and experiences of self- injuring behaviour they had a similar view of the phenomenon. The most common definition of a self- injuring behaviour was cutting, scratching or burning yourself. Although they don’t know the reason for it, the literature as well as the informants seem to agree that self-injuring behaviour is increasing in society. They emphasize that media, through the attention given to the phenomenon during the last years, could have an effect on the increase. Two of the most common reasons why an individual chose to hurt him- or herself, seem to be reduction of anxiety and/or seeking attention. The most important result found in this study is why people maintain this behaviour and what functions self-injuring behaviour serve them.</p>
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Självskadebeteende : en studie om sex professionellas syn på fenomenetAndersson, Helen, Ohlin, Annika January 2006 (has links)
The purpose of this study was trying to understand and explain why young people with psychological problems injure themselves by cutting, scratching and burning. The study also examine if self- injuring behaviour is an increasing problem in our society. Self-injuring behaviour is a phenomenon with dissimilar definitions. There are as many ways of injuring yourself as there are individuals who injure themselves. In this study six professionals, who through their work have contact with self- injuring people, have been interviewed. Their own view of self- injuring behaviour was put in comparison with the literature. It was found that despite their dissimilar educations and experiences of self- injuring behaviour they had a similar view of the phenomenon. The most common definition of a self- injuring behaviour was cutting, scratching or burning yourself. Although they don’t know the reason for it, the literature as well as the informants seem to agree that self-injuring behaviour is increasing in society. They emphasize that media, through the attention given to the phenomenon during the last years, could have an effect on the increase. Two of the most common reasons why an individual chose to hurt him- or herself, seem to be reduction of anxiety and/or seeking attention. The most important result found in this study is why people maintain this behaviour and what functions self-injuring behaviour serve them.
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The development of scratch test methodology and characterization of surface damage of polypropyleneWong, Min Hao 15 November 2004 (has links)
A new scratch test methodology is proposed. The new test methodology is
developed based on the principles of materials science and solid mechanics, which
include the consideration of material parameters, use of microscopy for image
analysis and the finite element method (FEM). The consistency and reproducibility of
test results are shown using a new scratch test device on two sets of neat and talcfilled
polypropylene (PP) systems. Three different test conditions, i.e., linear load
increase under constant rate, constant load under constant rate, and linear rate increase
under constant load, have been conducted to determine the most effective, informative
test conditions for evaluation of scratch resistance of polymers. Experimental
observations and FEM results show a good qualitative correlation. The unique
advantages of the new scratch test method for evaluating scratch resistance of
polymers are discussed. A systematic study of surface damage effected by a
progressive scratching load is performed on model polypropylene (PP) systems. Mar-scratch
and stress -whitening transitions can be readily observed, and the
corresponding critical loads determined. Distinctive scratch hardnesses and surface damage features are
found for different material systems. Visibility of scratched surface is quantified
using gray level analysis via a flatbed scanner and a commercial image analysis tool.
It is found that the onset of scratch visibility can be determined accurately and
reproducibly using the custom -built scratcher under progressive loading condition.
Talc particles are found to be responsible for the increased light scattering, leading to
greatly increased visibility. The observed scratch visibility is also found to be related
to the measured frictional force profiles. Approaches for producing scratch
resistant PP are discussed.
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Estudo da usinabilidade do ZERODUR® no torneamento de ultraprecisão com ferramenta de diamante de ponta única / Study of ZERODUR® machinability using single point diamond turningOtoboni, José Antonio 30 August 2013 (has links)
Alguns espelhos usados em câmeras de satélite devem apresentar qualidade superficial elevada. Eles são normalmente fabricados em ZERODUR®, um material vitrocerâmico, por meio de processos abrasivos. Observou-se que a qualidade da superfície do material deteriora-se algum tempo após a usinagem, necessitando assim de retrabalho. A causa mais influente desse fenômeno é o crescimento de trincas devido à corrosão sobtensão. Estas trincas são geradas pelas condições impostas nos processos convencionais de lapidação e polimento. Este trabalho apresenta um estudo sobre a usinabilidade do ZERODUR® utilizando torneamento de ultraprecisão com ferramenta de diamante de ponta única como uma alternativa a estes métodos tradicionais. Amostras de ZERODUR® foram submetidas a testes de indentação e riscamento a fim de se estudar as propriedades mecânicas do material, a transição dúctil-frágil e os mecanismos de remoção de material. Com base nesses testes, foi delineado um experimento fatorial do tipo 23 para avaliar a influência das seguintes variáveis de usinagem: profundidade de corte, nos níveis 0,4 e 0,2 \'mü\'m, taxa de avanço, nos níveis 0,3 e 0,1 \'mü\'m/rev e ângulo de saída da ferramenta, nos níveis -5º e -20º. As amostras do experimento foram usinadas em um torno de ultraprecisão com a ferramenta de diamante de ponta única. A qualidade superficial de cada combinação foi avaliada por microscopia eletrônica de varredura e perfilometria óptica interferométrica. Os resultados dos experimentos foram analisados estatisticamente, por meio de análise de variância (ANOVA). Para os intervalos das variáveis testadas verificou-se que o ângulo de inclinação da ferramenta é o que mais afeta a qualidade superficial. Ângulos com inclinações mais negativas (-20º) proporcionaram as melhores qualidades superficiais (em torno de 200 nm). Nos resultados não houve evidência de que o corte do material tenha ocorrido dentro do regime dúctil. Porém, a rugosidade superficial encontrada em algumas combinações de corte sugere que o torneamento de ultraprecisão pode ser uma alternativa ao processo lapidação que antecede o polimento. Este trabalho de caráter exploratório contribui com estimativas de alguns parâmetros ótimos para usinagem do ZERODUR®, fornecendo subsídios para pesquisas futuras sobre este tema. / Some mirrors used in satellite cameras must present a high surface quality. They are usually made of ZERODUR®, a brittle glass ceramic, by means of abrasive processes. It was observed that the surface quality of the material deteriorates some time after the machining, thus requiring rework. The most influential cause of this phenomenon is the crack growth due to stress corrosion. These cracks are generated by the conventional machining processes of lapping and polishing. This work presents a study on the machinability of ZERODUR® using ultraprecision turning with single-point diamond tool as an alternative to these traditional methods. ZERODUR® samples were subjected to indentation and nano-scratching tests in order to study the ductile-brittle transition and material removal mechanisms. After that, a \'2 POT.3\' factorial experiment was designed in order to assess the influence of three machining parameters on the resulting surface roughness, which are: depth of cut (tested at levels 0,4 and 0,2 \'mü\'m), feed rate (tested at levels 0,3 and 0,1 \'mü\'m/rev) and rake angle of the cutting tool (tested at levels -5º e -20º). The samples were turned with single-point diamond tool using different combinations of the parameters at the levels described above. The surface quality of each sample was evaluated using an interferometric optical profiler and a scanning electron microscope (SEM). The results of the experiments were statistically evaluated by means of Analysis Of Variance (ANOVA). For the ranges tested, it was found that the rake angle of the tool was the most influential parameter. The angle of -20º provided the best values for surface quality, which were around 200 nm. There was no evidence that the cut of the material occurred in the ductile regime, however, the obtained surface roughness showed that the ultraprecision turning may be a feasible alternative for the lapping process of optical components. This exploratory research contributes to the existing knowledge by providing estimates for optimal parameters of ZERODUR® machining, furnishing empirical basis for future research in this field.
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Estudo da usinabilidade do ZERODUR® no torneamento de ultraprecisão com ferramenta de diamante de ponta única / Study of ZERODUR® machinability using single point diamond turningJosé Antonio Otoboni 30 August 2013 (has links)
Alguns espelhos usados em câmeras de satélite devem apresentar qualidade superficial elevada. Eles são normalmente fabricados em ZERODUR®, um material vitrocerâmico, por meio de processos abrasivos. Observou-se que a qualidade da superfície do material deteriora-se algum tempo após a usinagem, necessitando assim de retrabalho. A causa mais influente desse fenômeno é o crescimento de trincas devido à corrosão sobtensão. Estas trincas são geradas pelas condições impostas nos processos convencionais de lapidação e polimento. Este trabalho apresenta um estudo sobre a usinabilidade do ZERODUR® utilizando torneamento de ultraprecisão com ferramenta de diamante de ponta única como uma alternativa a estes métodos tradicionais. Amostras de ZERODUR® foram submetidas a testes de indentação e riscamento a fim de se estudar as propriedades mecânicas do material, a transição dúctil-frágil e os mecanismos de remoção de material. Com base nesses testes, foi delineado um experimento fatorial do tipo 23 para avaliar a influência das seguintes variáveis de usinagem: profundidade de corte, nos níveis 0,4 e 0,2 \'mü\'m, taxa de avanço, nos níveis 0,3 e 0,1 \'mü\'m/rev e ângulo de saída da ferramenta, nos níveis -5º e -20º. As amostras do experimento foram usinadas em um torno de ultraprecisão com a ferramenta de diamante de ponta única. A qualidade superficial de cada combinação foi avaliada por microscopia eletrônica de varredura e perfilometria óptica interferométrica. Os resultados dos experimentos foram analisados estatisticamente, por meio de análise de variância (ANOVA). Para os intervalos das variáveis testadas verificou-se que o ângulo de inclinação da ferramenta é o que mais afeta a qualidade superficial. Ângulos com inclinações mais negativas (-20º) proporcionaram as melhores qualidades superficiais (em torno de 200 nm). Nos resultados não houve evidência de que o corte do material tenha ocorrido dentro do regime dúctil. Porém, a rugosidade superficial encontrada em algumas combinações de corte sugere que o torneamento de ultraprecisão pode ser uma alternativa ao processo lapidação que antecede o polimento. Este trabalho de caráter exploratório contribui com estimativas de alguns parâmetros ótimos para usinagem do ZERODUR®, fornecendo subsídios para pesquisas futuras sobre este tema. / Some mirrors used in satellite cameras must present a high surface quality. They are usually made of ZERODUR®, a brittle glass ceramic, by means of abrasive processes. It was observed that the surface quality of the material deteriorates some time after the machining, thus requiring rework. The most influential cause of this phenomenon is the crack growth due to stress corrosion. These cracks are generated by the conventional machining processes of lapping and polishing. This work presents a study on the machinability of ZERODUR® using ultraprecision turning with single-point diamond tool as an alternative to these traditional methods. ZERODUR® samples were subjected to indentation and nano-scratching tests in order to study the ductile-brittle transition and material removal mechanisms. After that, a \'2 POT.3\' factorial experiment was designed in order to assess the influence of three machining parameters on the resulting surface roughness, which are: depth of cut (tested at levels 0,4 and 0,2 \'mü\'m), feed rate (tested at levels 0,3 and 0,1 \'mü\'m/rev) and rake angle of the cutting tool (tested at levels -5º e -20º). The samples were turned with single-point diamond tool using different combinations of the parameters at the levels described above. The surface quality of each sample was evaluated using an interferometric optical profiler and a scanning electron microscope (SEM). The results of the experiments were statistically evaluated by means of Analysis Of Variance (ANOVA). For the ranges tested, it was found that the rake angle of the tool was the most influential parameter. The angle of -20º provided the best values for surface quality, which were around 200 nm. There was no evidence that the cut of the material occurred in the ductile regime, however, the obtained surface roughness showed that the ultraprecision turning may be a feasible alternative for the lapping process of optical components. This exploratory research contributes to the existing knowledge by providing estimates for optimal parameters of ZERODUR® machining, furnishing empirical basis for future research in this field.
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Assessing Sow Preference for Scratching Enrichment and Effectiveness in Farrowing CratesRebecca Kristine Smith (7480697) 17 October 2019 (has links)
<p>Effective
enrichments for farm animals are increasingly important to address public
concerns about farm animal welfare and improve the welfare of the animals we
raise. The public’s concern has increased in recent years as the management and
care that farmers give their animals has become more apparent to them. Some of
the conditions in which animals are kept are emotionally not appealing to the
public. One such condition is farrowing crates for sows and piglets. The sows
are confined in a small space with no social contact and cannot perform nesting
behaviors. Farrowing crates are widely used though, as they allow farmers to
handle piglets without fear of sow aggression, meet individual sow nutritional
needs, and personalize care. Piglet mortality due to crushing is also decreased
with crate use. Sow welfare in farrowing crates can be improved through
environmental enrichments. Enrichments improve welfare by increasing
species-specific behaviors, creating a more complex environment, reducing
abnormal behaviors, and increasing an animal’s ability to cope with stressful
situations. For pigs, different enrichments have been shown to decrease
stereotypies, like sham chewing and bar biting, decrease harmful redirected
behavior towards pen mates, like tail biting and belly nosing, increased
exploratory behavior, and increase positive affect. Straw has been found to be
the best enrichment for pigs because it allows them to perform motivational
behaviors such as rooting, foraging, and nest building. It is also complex,
manipulatable, destructible, and ingestible, which are important attributes of
effective enrichments. Unfortunately, straw cannot be used in farms that have
slurry systems, as the straw will fall through the slats into the pit below and
cause drainage issues. This includes farrowing crates. There have been a few
studies on alternative enrichments for sows in crates, like cloth tassels, but
they are not as effective as straw and are rarely used on farm.</p>
<p> Most enrichments target pigs’
motivations to forage, root, graze, or build nests. Pigs perform other
behaviors and may have other motivations that enrichments have not targeted
yet. One such behavior is scratching. In a semi-natural environment, pigs will
rub against trees and bushes. In confinement, pigs rub on fences, walls, and
even allow people to scratch them with their hands. There have been no recorded
studies done on scratching enrichment for pigs. Many studies have been done in
the dairy industry exploring rotating brushes. These brushes have been
implemented successfully on commercial farms and are used by cows to groom and
scratch themselves. A similar device may allow pigs to also satisfy their itch.
Our aim is to provide scratching enrichment to sows in farrowing crates. Since
there have been no studies recorded on scratching enrichment or scratching in
pigs in general, several steps had to take place before addressing the topic
for sows in crates. The first project’s aim was to see what materials pigs
prefer to scratch on and their willingness to use such an enrichment.</p>
<p><a> The first project consisted of 2 experiments. Exp. 1 was
a pilot study where 5 different materials on scratch posts were presented to a
pen of gestating sows. The scratch posts were constructed from polyvinyl
chloride (<b>PVC</b>) pipes, boards, and a gate post. Five different materials
were attached to the boards: white, soft, long-bristled brushes (<b>White Brush</b>),
red, hard, short-bristled brush (<b>Red Brush</b>), black, short-bristled,
astro-turf-like mat (<b>Plastic Mat</b>), colorful coir, hard, short-bristled
mat (<b>Fiber Mat</b>), and blue, plastic, large-round-bristled combs (<b>Plastic
Combs</b>). The 8 sows received all 5 scratch posts in their pen for a
habituation day and then 7 d of testing. During testing, video was continuously
recorded from which 2 behaviors were collected; scratching and interacting.
Sows scratched the most on Plastic Mat followed by Fiber Mat, Plastic Combs,
and Red Brush. The White Brush was scratched on the least. The top 3 preferences
were chosen to proceed to Exp. 2.</a></p>
<p> Experiment 2 for sow preference was
performed on several pens (N=14) of sows and gilts with Plastic Mat, Fiber Mat,
and Plastic Combs to narrow the preference down to 2 materials to proceed to
the farrowing crates. The experiment was carried out in repetitions. Each
repetition tested 4 pens at a time. The scratch posts were modified from Exp. 1
and each material was placed in a pen. Due to material destruction only 2
repetitions were carried out, both ending a little early (N=8). During the
first repetition (<b>Rep 1</b>), sows ate and destroyed all the Plastic Combs
within 2 d. The Plastic Comb scratch posts were pulled from the study and the
second repetition (<b>Rep 2</b>) only had the Plastic Mat and Fiber Mat
represented. An observation was made that one of the pens in Rep1 had extra
feed on their floor and were not destroying their materials as fast as the
other pens. So for Rep 2, more modifications to the scratch posts were made and
the sows were given a little extra feed. The scratch posts were still destroyed
in Rep 2 proving that the sows’ hunger and motivation to perform oral
manipulations overwhelmed scratching behaviors. However, from the data that was
collected sows spent more time and more frequently interacted with the Fiber
Mat compared to the Plastic Mat. They more frequently and spent more time
interacting than scratching with the enrichments but scratched on both
enrichments the same amount of time and frequency (Durations: F<sub>1,112.6 </sub>=
13.63, <i>P</i> = 0.0003; Frequencies: F<sub>1,111.9 </sub>= 19.72, <i>P</i>
< 0.0001).</p>
<p> The
plastic and fiber mats were presented to sows in farrowing crates for the
second project by default. Sows (N=18) of parities 2 (<b>P2</b>) and 3 (<b>P3</b>)
were housed for 25 d and assigned no enrichment (<b>Control</b>)
or to a scratch pad treatment of plastic mats (<b>Plastic</b>) or fiber mats (<b>Fiber</b>).
All were assessed for lesions, abnormal behaviors, eating and scratching
behaviors, and time spent in different postures and behaviors. Scratching bouts
occurred in short durations and were intermittent throughout the day. Parity
2 Plastic sows scratched for a longer total duration than P2 and P3 Fiber sows,
P3 Plastic sows, and P2 Control sows (F<sub>2,11 </sub>= 11.94,<i> P</i> =
0.002). Parity 2 Plastic sows also displayed scratching bouts more frequently
than all except P3 Control sows (F<sub>2,11 </sub>= 18.46, <i>P</i> = 0.0003). There
were no body lesion differences between treatments (<i>P</i> > 0.05).
Abnormal behaviors (<i>P</i> > 0.05) and proportion of time spent in
different postures (F<sub>2,94 </sub>= 0.0003, <i>P</i> = 0.999) did not differ
among treatments. </p>
In conclusion, if a sow is experiencing hunger
while in gestation pens this motivation may be overwhelming any other behavior
needs. Scratch posts were destroyed and eaten. In this sort of environment,
focusing on an enrichment that meets the need to forage and root would be more successful.
Sows still scratched on the posts, so their preference and scratching use was
still recorded to an extent to proceed to the experiment in farrowing crates.
In farrowing crates, plastic scratch pads may be a
suitable enrichment as they increased the natural behavior of scratching and
did not increase abnormal behaviors. More research is needed to refine the
scratch pad design and identify additional measures needed to examine the
suitability of scratch pads as a form of environmental enrichment for sows in
farrowing crates. In addition, the behavioral characteristics and sows’
underlying motivation for scratching need to be studied because very little is
known about scratching behavior of sows. If sows are motivated to scratch, and
scratching helps improve their welfare, then scratching enrichment may be
beneficial to sows and farmers.
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Kattifiering : Anpassa ditt hem för kattenLööv, Ofelia January 2018 (has links)
Katten är bland de vanligaste husdjuren i Sverige och att ha innekatt blir alltmer vanligt. Katten har många behov som exempelvis att få röra på sig och vässa klorna, vilket är stora aspekter i deras natur. Att aktivera katten är en viktig del i deras vardag för att undvika att de utvecklar oönskade beteenden som exempelvis att riva sin ägare. Bor man på en mindre yta kan det dock vara mer utmanande samt problematiskt att tillfredsställa detta behov tillräckligt. Mitt fokus har därmed varit att ta fram ett alternativt koncept på klösmöbel som även passar kattägare som bor mindre. På dagens marknad kräver de stora varianterna på klösmöbler ofta mycket golvyta, vilket kan bli ett problem om man bor mindre. Idag är det vanligt att kattägare bygger egna klösmöbler, men det är tidskrävande och därmed inte alltid önskvärt. Under projektets gång har jag intervjuat er kattägare och funnit ett behov av en större klösmöbel som passar in i det vardagliga hemmet och som lämpar sig om man bor mindre. En enkät skickades ut i olika kattforum där det tydligt syntes att kattägare ser ett värde om de själva kunde utnyttja klösmöbeln. Därmed designade jag en klösmöbel i kombination med en möbel som ofta nns i det vardagliga hemmet för både katten och kattägaren. / The cat is among the most popular pets in Sweden and having an indoor cat has become more common. A cat has many needs. For example, they need to be activated through play and allowed to sharpen their claws by scratching since these are major aspects in their nature. Activating your cat is an important part of their everyday life and to prevent them from obtaining unwanted behaviours, such as scratching their owner. However, satisfying the needs of a cat can become a di cult task and problematic for cat owners living more cramped home accommodations. Therefore, my focus has been to develop an alternate concept of a scratching post that also suits cat owners living in smaller homes. Larger scratching posts on today’s market often require considerable space on the oor, which can be a problem if you have a small home. It has become common for cat owners to construct their own scratching posts today, but that can be rather time consuming and thus often not desirable. During the course of my project, I have interviewed multiple cat owners and found a need for a larger scratching post that blends into the ordinary household. A survey was submitted onto various cat forums where the response clearly showed that cat owners found value in the concepts where they themselves could utilise the scratching post. Thus, I combined a scratching post with a typical type of furniture you often see in the ordinary household, one that can be used by both cat and cat owner.
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Undersökande av kli-ljud inom ASMR i en neutral ljudmiljö / A study of scratching sounds within ASMR in a neutral sound environmentKöhler, Anders January 2018 (has links)
Denna studie har utförts med bas i frågeställningen huruvida rosa brus kan nyttjas för att replikera den övergripande ljuddynamik som förekommer inom kli-inriktade ASMR-verk med hänseende till envelope-egenskaper samt övergripande frekvensregister och hur den akustiska karaktären av en sådan ljudartefakt kan komma att uppfattas av ett antal respondenter. Tidigare forskning inom ASMR har jämförts med auditivt inriktad litteratur för att styrka relevansen av denna sortens studie varpå ytterligare framtida forskningsutsikter har spekulerats kring. Angreppsmetoden har grundats i användandet av en noise gate-teknik med fokus på side chain-kompression samt en vocoder för replikerandet av den ljuddynamik som har inhämtats från ett kli-inriktat ASMR-verk. Ljudtekniska data för designen av artefakten införskaffades med hjälp av spektrogramanalyser och kvalitativa intervjuer stod till grund för experimentets utförande. Studieresultaten visade huvudsakligen på att rosa brus sannolikt besitter en god förmåga att approximera kli-ljud i det tekniska sammanhang som har studerats och därmed inge behag hos en lyssnare. Även övergångar mellan distinkt olika ljudsegment av denna typ visade sig besitta mycket goda möjligheter att inge behag.
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Influence of Surface Carbon Content on the Wear of Threaded Connections in Rock Drilling SteelsHälsing, Andreas January 2023 (has links)
This thesis work was conducted at Luleå University of Technology in collaboration with Sandvik Rock Tools. The aim of the work was to determine the influence of carbon content on the wear performance in carburized steel in the dry contact interface of threaded connections between drill rods. In order to investigate this, samples of drill rod steel were carburized to three different carbon concentrations and shot peened to replicate the production process of a drill rod. The samples were wear tested by utilizing a twin-disc wear tester with one disc rotating at 100 RPM and the other at 3000 RPM to mimic the operating conditions in the threaded connection between drill rods. The results was evaluated by wear rate, surface topography, hardness as well as optical analysis by light optical microscopy and scanning electron microscopy. The results show that an increased surface carbon content provide a decrease in wear rate and an increase in hardness in the surface layer that undergo microstructural changes due to the frictional heat and contact pressure during wear testing. The primary wear mechanisms were identified as plastic deformation, adhesive scratching and material removal through delamination.
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