142 resultados para right-angle prism


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Fast calculation of quantities such as in-cylinder volume and indicated power is important in internal combustion engine research. Multiple channels of data including crank angle and pressure were collected for this purpose using a fully instrumented diesel engine research facility. Currently, existing methods use software to post-process the data, first calculating volume from crank angle, then calculating the indicated work and indicated power from the area enclosed by the pressure-volume indicator diagram. Instead, this work investigates the feasibility of achieving real-time calculation of volume and power via hardware implementation on Field Programmable Gate Arrays (FPGAs). Alternative hardware implementations were investigated using lookup tables, Taylor series methods or the CORDIC (CoOrdinate Rotation DIgital Computer) algorithm to compute the trigonometric operations in the crank angle to volume calculation, and the CORDIC algorithm was found to use the least amount of resources. Simulation of the hardware based implementation showed that the error in the volume and indicated power is less than 0.1%.

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This article assesses undergraduate teaching students’ assertion that there are no right and wrong answers in teaching philosophy. When asked questions about their experiences of philosophy in the classroom for primary children, their unanimous declaration that teaching philosophy has ‘no right and wrong answers’ is critically examined across the three sub-disciplinary areas to which they were generally referring, namely, pedagogy, ethics, and epistemology. From a pedagogical point of view, it is argued that some teaching approaches may indeed be more effective than others, and some pupils’ opinions less defensible, but pedagogically, in terms of managing the power relations in the classroom, it is counter-productive to continually insist on notions of truth and falsity at every point. From an ethical point of view, it is contended that anti-realist approaches to meta-ethics may represent a viable intellectual position, but from the point of view of normative ethics, notions of right and wrong still retain significant currency. From an epistemological point of view, it is argued using Karl Poppers’ work that while it may be difficult to determine what constitutes a right answer, determining a wrong one is far more straightforward. In conclusion, it is clear that prospective teachers engaging in philosophy in the classroom, and also future teachers in general, require a far more nuanced philosophical understanding of the notions of right and wrong and truth and falsity. In view of this situation, it we wish to promote the effective teaching of philosophical thinking to children, or produce educators who can understand the conceptual limits of the claims they make and their very real and often serious practical and social consequences, it is recommended that philosophy be reinstated to a fundamental, foundational place within the pre-service teaching curriculum.

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Female genital mutilation (FGM) is a cultural practice involving the deliberate, non-therapeutic physical modification of young girls’ genitalia. FGM can take several forms, ranging from smaller incisions, to removal of the clitoris and labia, and narrowing or even closing of the vagina. FGM predates and has no basis in the Koran, or any other religious text. Rather, it is a cultural tradition, particularly common in Islamic societies in regions of Africa, motivated by a patriarchal society’s desire to control female bodies and lives. The primary reason for this desire for control is to ensure virginity at marriage, thereby preserving family honour, within a patriarchal social structure where females’ value as persons is intrinsically connected to, and limited to, their worth as virgin brides. Recent efforts at legal prohibition and practical eradication in a growing number of African nations mark a significant turning point in how societies treat females. This shift in cultural power has been catalysed by a concern for female health, but it has also been motivated by an impulse to promote the human rights of girls and women. Although FGM remains widely practiced and there is much progress yet to be made before its eradication, the rights-based approach which has grown in strength embodies a marked shift in cultural power which reflects progress in women’s and children’s rights in the Western world, but which is now being applied in a different cultural context. This chapter reviews the nature of FGM, its prevalence, and health consequences. It discusses recent legal, cultural and practical developments, especially in African nations. Finally, this chapter raises the possibility that an absolute human right against FGM may emerge.

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Higher than usual rates of interest charged by lenders on short term loans is not of itself considered to be a penalty or evidence of unconscionable conduct. These types of lenders often charge higher rates to take account of increased losses from higher than usual defaults by borrowers.

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The significance of the proposed name of a building to buyers of units off the plan has received recent attention in Queensland and the ACT with differing results. In Gough v South Sky Investments Pty Ltd the Queensland Court of Appeal concluded that the name of the building was not an essential term of the contract and rejected a claim by a number of buyers to terminate their contracts because of the change of name from Oracle to Peppers. In contrast, Rares J in the Federal Court decision of Madison Constructions Pty Ltd v Empire Building Group (ACT) Pty Ltd considered that the name of the building in a proposed development could potentially form the basis of misleading conduct about the association of the seller with a particular development corporation.

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The aftermath of the Queensland floods of January 2011 continues to be played out in the courts. The effect of the floods on such a large scale has awakened the use of some statutory provisions that have not previously been litigated .Section 64 of the Property Law Act 1974 (Qld) is such a section. A version of this provision appears as s 34 of the Sale of Land Act 1982 (Vic). Broadly speaking, these sections permit a buyer of a dwelling house which has been damaged or destroyed between contract and completion to rescind the contract and recover their deposit provided that the rescission notice is given prior to "the date of completion or possession". The Court of Appeal decision of Dunworth v Mirvac Queensland Pty Ltd [2011] QCA 200 appears to be the first litigation upon the application of the section since it came into force in 1975.

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Teaching basic principles of colonisation, contamination and infection has revolutionised approaches to wound care. Wound colonisation is classified as the existence of bacteria with no obvious host reaction (Carville 2005). The act of wound contamination is recognised as introducing micro-organisms into the wound (Ellis 2004). Wound infection is an invasion and multiplication of micro-organisms causing localised and systemic effects (Baranoski and Ayello 2004). Through clinical practice, nurses inadvertently engage in wound contamination thus setting the environment for wound infection.

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This paper describes and explains the social worlds of a group of young Murris who are engaged in chroming (paint sniffing) and who sleep rough in inner Brisbane. In particular, the paper considers the ways young Indigenous drug users describe their marginalisation from wider society and its structures of opportunity, but it also includes some reflections from their youth worker and a young man who frequents the young people’s squat. The paper demonstrates the centrality of racism and material disadvantage to the experience of a group of young Aboriginal and Torres Strait Islander sniffers, a perspective largely unreflected in the literature on Indigenous volatile substance misuse. Further, the young people’s ways of interacting with the broader society are described to explain the ways their rejection of mainstream norms form a significant political response to their marginality and reflect, at least in part, the wider Indigenous historical experience. The work draws on theories of alienation and subculture to analyse the young people’s descriptions of their social estrangement and the formation of the ‘paint sniffer group’. It is concluded that paint sniffing among urban Indigenous youth is, at least in part, an obnoxious and encoded distillation of a wider Indigenous rebuttal of broader societal norms, and that the dominant — normalising — modes of treatment risk further alienating an already oppositional group of young people.

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The future emergence of many types of airborne vehicles and unpiloted aircraft in the national airspace means collision avoidance is of primary concern in an uncooperative airspace environment. The ability to replicate a pilot’s see and avoid capability using cameras coupled with vision based avoidance control is an important part of an overall collision avoidance strategy. But unfortunately without range collision avoidance has no direct way to guarantee a level of safety. Collision scenario flight tests with two aircraft and a monocular camera threat detection and tracking system were used to study the accuracy of image-derived angle measurements. The effect of image-derived angle errors on reactive vision-based avoidance performance was then studied by simulation. The results show that whilst large angle measurement errors can significantly affect minimum ranging characteristics across a variety of initial conditions and closing speeds, the minimum range is always bounded and a collision never occurs.

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The legal framework that operates at the end of life in Australia needs to be reformed. • Voluntary euthanasia and assisted suicide are currently unlawful. • Both activities nevertheless occur not infrequently in Australia, in part because palliative care cannot relieve physical and psychological pain and suffering in all cases. • In this respect, the law is deficient. The law is also unfair because it doesn’t treat people equally. Some people can be helped to die on their own terms as a result of their knowledge and/or connections while some are able to hasten their death by the refusal of life-sustaining treatment. But others do not have access to the means for their life to end. • A very substantial majority of Australians have repeatedly expressed in public opinion polls their desire for law reform on these matters. Many are concerned at what they see is happening to their loved ones as they reach the end of their lives, and want the confidence that when their time comes they will be able to exercise choice in relation to assisted dying. • The most consistent reason advanced not to change the law is the need to protect the vulnerable. There is a concern that if the law allows voluntary euthanasia and assisted suicide for some people, it will be expanded and abused, including pressures being placed on highly dependent people and those with disabilities to agree to euthanasia. • But there is now a large body of experience in a number of international jurisdictions following the legalisation of voluntary euthanasia and/or assisted suicide. This shows that appropriate safeguards can be implemented to protect vulnerable people and prevent the abuse that opponents of assisted dying have feared. It reveals that assisted dying meets a real need among a small minority of people at the end of their lives. It also provides reassurance to people with terminal and incurable disease that they will not be left to suffer the indignities and discomfort of a nasty death. • Australia is an increasingly secular society. Strong opposition to assisted death by religious groups that is based on their belief in divine sanctity of all human life is not a justification for denying choice for those who do not share that belief. • It is now time for Australian legislators to respond to this concern and this experience by legislating to enhance the quality of death for those Australians who seek assisted dying.

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Energy represents the cornerstone of modern life. However, current patterns of energy production are unsustainable. This is true for both the developed and developing worlds. In this context, this paper considers how, from a conceptual perspective, the law can contribute to more sustainable patterns of energy production can be addressed. The approach that this paper adopts is to consider two of the most important concepts that are relevant to the governance of modern environmental and societal challenges: human dignity and sustainable development. It is within this context that this paper contends that the convergence of these concepts provides the platform for a novel approach to encourage the sustainable production of energy by way of a ‘right to sustainable energy’. With this in mind, this paper considers the forum in which a right to sustainable energy may be developed and outlines the content of the proposed right.

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Introduction: Calculating segmental (vertebral level-by-level) torso masses in Adolescent Idiopathic Scoliosis (AIS) patients allows the gravitational loading on the scoliotic spine during relaxed standing to be estimated. This study used supine CT scans of AIS patients to measure segmental torso masses and explored the joint moments in the coronal plane, particularly at the apex of a scoliotic major curve. Methods: Existing low dose CT data from the Paediatric Spine Research Group was used to calculate vertebral level-by-level torso masses and joint moments occurring in the spine for a group of 20 female AIS patients with right sided thoracic curves. The mean age was 15.0 ± 2.7 years and all curves were classified Lenke Type 1 with a mean Cobb angle 52 ± 5.9°. Image processing software, ImageJ (v1.45 NIH USA) was used to create reformatted coronal plane images, reconstruct vertebral level-by-level torso segments and subsequently measure the torso volume corresponding to each vertebral level. Segment mass was then determined by assuming a tissue density of 1.04x103 kg/m3. Body segment masses for the head, neck and arms were taken from published anthropometric data (Winter 2009). Intervertebral joint moments in the coronal plane at each vertebral level were found from the position of the centroid of the segment masses relative to the joint centres with the segmental body mass data. Results and Discussion: The magnitude of the torso masses from T1-L5 increased inferiorly, with a 150% increase in mean segmental torso mass from 0.6kg at T1 to 1.5kg at L5. The magnitudes of the calculated coronal plane joint moments during relaxed standing were typically 5-7 Nm at the apex of the curve, with the highest apex joint torque of 7Nm. The CT scans were performed in the supine position and curve magnitudes are known to be 7-10° smaller than those measured in standing, due to the absence of gravity acting on the spine. Hence, it can be expected that the moments produced by gravity in the standing individual will be greater than those calculated here.

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Near work may play an important role in the development of myopia in the younger population. The prevalence of myopia has also been found to be higher in occupations that involve substantial near work tasks, for example in microscopists and textile workers. When nearwork is performed, it typically involves accommodation, convergence and downward gaze. A number of previous studies have examined the effects of accommodation and convergence on changes in the optics and biometrics of the eye in primary gaze. However, little is known about the influence of accommodation on the eye in downward gaze. This thesis is primarily concerned with investigating the changes in the eye during near work in downward gaze under natural viewing conditions. To measure wavefront aberrations in downward gaze under natural viewing conditions, we modified a commercial Shack-Hartmann wavefront sensor by adding a relay lens system to allow on-axis ocular aberration measurements in primary gaze and downward gaze, with binocular fixation. Measurements with the modified wavefront sensor in primary and downward gaze were validated against a conventional aberrometer using both a model eye and in 9 human subjects. We then conducted an experiment to investigate changes in ocular aberrations associated with accommodation in downward gaze over 10 mins in groups of both myopes (n = 14) and emmetropes (n =12) using the modified Shack-Hartmann wavefront sensor. During the distance accommodation task, small but significant changes in refractive power (myopic shift) and higher order aberrations were observed in downward gaze compared to primary gaze. Accommodation caused greater changes in higher order aberrations (in particular coma and spherical aberration) in downward gaze than primary gaze, and there was evidence that the changes in certain aberrations with accommodation over time were different in downward gaze compared to primary gaze. There were no obvious systematic differences in higher order aberrations between refractive error groups during accommodation or downward gaze for fixed pupils. However, myopes exhibited a significantly greater change in higher order aberrations (in particular spherical aberration) than emmetropes for natural pupils after 10 mins of a near task (5 D accommodation) in downward gaze. These findings indicated that ocular aberrations change from primary to downward gaze, particularly with accommodation. To understand the mechanism underlying these changes in greater detail, we then extended this work to examine the characteristics of the corneal optics, internal optics, anterior biometrics and axial length of the eye during a near task, in downward gaze, over 10 mins. Twenty young adult subjects (10 emmetropes and 10 myopes) participated in this study. To measure corneal topography and ocular biometrics in downward gaze, a rotating Scheimpflug camera and an optical biometer were inclined on a custom built, height and tilt adjustable table. We found that both corneal optics and internal optics change with downward gaze, resulting in a myopic shift (~0.10 D) in the spherical power of the eye. The changes in corneal optics appear to be due to eyelid pressure on the anterior surface of the cornea, whereas the changes in the internal optics (an increase in axial length and a decrease in anterior chamber depth) may be associated with movement of the crystalline lens, under the action of gravity, and the influence of altered biomechanical forces from the extraocular muscles on the globe with downward gaze. Changes in axial length with accommodation were significantly greater in downward gaze than primary gaze (p < 0.05), indicating an increased effect of the mechanical forces from the ciliary muscle and extraocular muscles. A subsequent study was conducted to investigate the changes in anterior biometrics, axial length and choroidal thickness in nine cardinal gaze directions under the actions of the extraocular muscles. Ocular biometry measurements were obtained from 30 young adults (10 emmetropes, 10 low myopes and 10 moderate myopes) through a rotating prism with 15° deviation, along the foveal axis, using a non-contact optical biometer in each of nine different cardinal directions of gaze, over 5 mins. There was a significant influence of gaze angle and time on axial length (both p < 0.001), with the greatest axial elongation (+18 ± 8 μm) occurring with infero-nasal gaze (p < 0.001) and a slight decrease in axial length in superior gaze (−12 ± 17 μm) compared with primary gaze (p < 0.001). There was a significant correlation between refractive error (spherical equivalent refraction) and the mean change in axial length in the infero-nasal gaze direction (Pearson's R2 = 0.71, p < 0.001). To further investigate the relative effect of gravity and extraocular muscle force on the axial length, we measured axial length in 15° and 25° downward gaze with the biometer inclined on a tilting table that allowed gaze shifts to occur with either full head turn but no eye turn (reflects the effect of gravity), or full eye turn with no head turn (reflects the effect of extraocular muscle forces). We observed a significant axial elongation in 15° and 25° downward gaze in the full eye turn condition. However, axial length did not change significantly in downward gaze over 5 mins (p > 0.05) in the full head turn condition. The elongation of the axial length in downward gaze appears to be due to the influence of the extraocular muscles, since the effect was not present when head turn was used instead of eye turn. The findings of these experiments collectively show the dynamic characteristics of the optics and biometrics of the eye in downward gaze during a near task, over time. These were small but significant differences between myopic and emmetropic eyes in both the optical and biomechanical changes associated with shifts of gaze direction. These differences between myopes and emmetropes could arise as a consequence of excessive eye growth associated with myopia. However the potentially additive effects of repeated or long lasting near work activities employing infero-nasal gaze could also act to promote elongation of the eye due to optical and/or biomechanical stimuli.