...Choosing appropriate glasses and athermalizing a lens system with only one metal by James Wu, jamesw@optics.arizona.edu, ywuumme99@excite.com Figure 1 shows a typical opto-mechanical design for athermalizing a lens system using two metals with dissimilar CTE’s. However, with the vast numbers of glasses to choose from, an athermal technique using only one metal as the metering structure is presented. A look-up table is provided for choosing the glass combinations that yield βlens = αmetal. Introduction In designing a lens system, it is common to start with a known design form and to use familiar glass types. After the optical design evolves to a mature stage, then the mechanical structures are “wrapped around” the prescribed optics. Different opto-mechanical athermal techniques have been developed for this serial approach. However, the mechanical design is strongly influenced by the near-finished lens prescription. For example, Figure 1 shows the opto-mechanical designs suitable for athermalizing some already prescribed lens systems. In order to maintain focus over some temperature fluctuations, two structural materials with dissimilar CTE’s and lengths are chosen to match the change in the focal length. The complexity in this opto-mechanical design adds volume, different materials, additional parts, handling, and assembling to the overall optical system. [pic][pic] (1a) (1b) Figure 1: Athermalizing a triplet and a doublet by matching (α1L1 ± α2L2) of the metering...
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...Earth-bound vs Space-based Telescopes Why construct and operate telescopes in Earth orbit ? To address this question, contrast the advantages and disadvantages of telescopes on the ground and in space. Keep in mind that the Hubble Space Telescope is NOT the only space telescope. Advantages: • Orbiting telescopes are NOT affected by the image smearing caused by Earth’s atmospheric motions, hence they can produce much “sharper” images The Hubble Telescope records optical images with a resolution as sharp as 0.05 arc seconds. • Space-based telescopes can collect energy from the entire electromagnetic spectrum, not just the portion that passes through our atmosphere. New “windows” on the cosmos are open to our view. • Day and night are not the same in orbit as on the ground, permitting telescopes to observe for much longer times at some locations on the sky. Disadvantages: • Telescopes on the ground can be built with much larger mirrors. Compare the Keck telescope’s 10-meter mirror with Hubble’s 2.4 meter mirror. Placing massive objects in orbit remains an expensive proposition. The largest optical and radio telescopes are still Earth-bound. • Ground-based telescopes don’t move at 5 km/sec, don’t have to carry their own power source and communications gear, and don’t need to worry about orbiting debris crashing into them. These “features” drive up the cost of designing, launching and operating space-based telescopes. • Ground-based telescopes...
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...The Great Aberration is the period of rupture in United States-China relations that lasted about 20 years since 1950s. The Americans at the time feared about communism, which was so rampant in Asian nations, especially in China. Because Americans had relatively good relationship with China for a period of time, and the People’s Republic of China’s leader, Mao Zedong, showed great hospitality to the US, Americans undervalued their traditional support of Asian Nationalism of China. The Truman Administration’s new foreign policy included how the US should treat the Communist countries in Asia and Europe, and the policy was very aggressive towards them. The policy contained very strong restrictions on the development of China as modern powerhouse, and it offended China’s national susceptibilities. Shortly after the introduction of the policy, the two previously friendly nations’ relation got worse. However, unlike the Cohen’s claim, the sudden change in relation between nations are not very rare....
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...4. “The sodomite had been a temporary aberration; the homosexual was now species.” Explain what Foucault means by this remark with reference to the nineteenth century process he calls “the medicalisation of the sexually peculiar”. At the heart of the statement and references contained in the title are illustrations of how power is expressed through normative discourse in Western capitalist society. The process of how an act once termed ‘sodomy’ became transformed into the term ‘homosexual’ is fundamental to the nature of power in general and to the mechanism of discourse specifically. Foucault draws our attention to domains of discourse that are characterised by establishing quantifiable knowledge as truth, which society affords positions of authority, such as the medical profession. This authoritative mechanism was an instrument that was applied to an existing system of sexual relation governance resulting in a control-dynamic between power, knowledge and sex. The medicalisation of sexuality through discourse spawned a categorisation of the individual as determined by their sexual identity in a process of transforming experience into knowledge, knowledge into truth, and truth into reality. Foucault’s reference to the ‘sexually peculiar’ draws our attention to the delineation between the procreative model of relationships and all other pleasure-centred sexual acts. The child-bearing relationship’s sexual activities were regulated and protected at the exclusion...
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...Marshall, J., Cheroske, A.G., Chiou, T. 2003. Polarization Vision and Its Role in Biological Signaling. Integrative and Comparative Biology. 43, 4: 549-558. Mäthger, L.M., Barbosa, A., Miner, S., Hanlon, R.T. 2006. Color blindness and contrast perception in cuttlefish (Sepia officinalis) determined by a visual sensorimotor assay. Vision Research. 46, 11: 1746-1753. Mäthger, L.M., Shashar, N., Hanlon, R.T. 2009. Do cephalopods communicate using polarized light reflections from their skin? Journal of Experimental Biology. 212: 2133-2140. Ritcher, J.N., Hochner, B., Kuba, M.J. 2016. Pull or Push? Octopuses Solve a Puzzle Problem. Plos One. Stubbs, A.L., Stubbs, C.W. 2016. Spectral discrimination in color blind animals via chromatic aberration and pupil shape. Proceedings of the National Academy of Sciences of the United States of America. 113,...
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...specimen, the electron beam carries information about the structure of the specimen that is magnified by the objective lens system of the microscope. The spatial variation may be viewed by projecting the magnified electron image onto a fluorescent viewing screen coated with a phosphor or scintillator material such as zinc sulfide. Alternatively, the image can be photographically recorded by exposing a photographic film or plate directly to the electron beam or a fibre optic light-guide to the sensor of a CCD (charge-coupled device) camera. The image detected by the CCD may be displayed on a computer. Resolution of the TEM is limited primarily by spherical aberration, but new generations of aberration correctors have been able to partially overcome spherical aberration to increase resolution. Hardware correction of spherical aberration for the HRTEM has allowed the production of images with resolution below 0.5 angstrom (50...
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...used to focus light. A lens is an optical device which transmits and refracts light, converging or diverging the beam.[citation needed] A simple lens consists of a single optical element. A compound lens is an array of simple lenses (elements) with a common axis; the use of multiple elements allows more optical aberrations to be corrected than is possible with a single element. Lenses are typically made of glass or transparent plastic. Elements which refract electromagnetic radiation outside the visual spectrum are also called lenses: for instance, a microwave lens can be made from paraffin wax. The variant spelling lense is sometimes seen. While it is listed as an alternative spelling in some dictionaries, most mainstream dictionaries do not list it as acceptable.[1][2] Contents * 1 History * 2 Construction of simple lenses * 2.1 Types of simple lenses * 2.2 Lensmaker's equation * 2.2.1 Sign convention of lens radii R1 and R2 * 2.2.2 Thin lens equation * 3 Imaging properties * 4 Aberrations * 4.1 Spherical aberration * 4.2 Coma * 4.3 Chromatic aberration * 4.4 Other types of aberration * 4.5 Aperture diffraction * 5 Compound lenses * 6 Other types * 7 Uses * 8 See also * 9 References * 10 Bibliography * 11 External links * 11.1 Simulations History | This section requires expansion with: history after 1758. (January 2012) | See also: History of optics and...
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...abandon yourself to something verb literary to feel an emotion so strongly that you let it control you completely * She abandoned herself to grief. * He abandoned himself to despair. * He abandoned himself to his emotions. abase yourself verb formal to behave in a way that shows you accept that someone has complete power over you * The members of the Political Executive Committee abased themselves once more. * She won’t abase herself by listening to his criticism. abate verb formal to become less strong or decrease * We waited for the wind/storm to abate. * The storm showed no sign of abating. * They waited for the crowd’s fury to abate. * Public anger does not appear to be abating. * The storm/wind/rain has started to abate. * The fighting in the area shows no sign of abating. * The excitement has abated. * The storms had abated by the time they rounded Cape Horn. * Steps are to be taken to abate pollution. * The pain in my shoulder abated after a day. * The town abated taxes on new businesses. * Our desire for consumer goods has not abated. * Gains in oil prices are unlikely to abate within the next few months. * Inflation is finally showing signs of abating. * The mayor plans to abate air pollution in the city by limiting traffic. * By the weekend, the storms had abated. * Public anger does not appear to be abating. * The level of wage settlements has shown no signs of abating...
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...GUIDELINES FOR FRAMING TERM PAPER PHY106 (Applied Phyics) 1. The Term Paper should be strictly in HAND WRITING of the respective student and submitted in hard copy. 2. The term paper comprises of 30 marks the division of which is following: a) 5 marks-----Term paper review (to be submitted as per date in the following document). b) 15 marks---Final term paper (to be submitted as per date in the following document) c) 10------Viva voce (conducted in respective tutorial) 3. The Final term paper should have the following components: a) Title page as per Annexure I. b) Abstract of work undertaken c) Acknowledgement. d) Table of contents. e) Introduction. f) Core chapters. g) Applications and future prospective. h) Conclusions and results (if any). i) References cited. EACH OF THE ABOVE COMPONENTS HAS MARKS. ANNEXURE-I TERM PAPER PHY106: Applied PHYSICS TOPIC NAME--- Date of allotment: Date of submission: Submitted to— Points to be noted: 1. Term Paper should be submitted as hard copy only. 2. Term Paper should be submitted in proper format as specified in this document. 3. No change in the term paper topic will be entertained. 4. Please check your topic carefully. 5. No marks for quantity but quality will be entertained. IMPORTANT POINTS REGARDING TERM PAPER A term paper is an innovative course specific long duration activity to be completed by...
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...OPPOSITE EXTREMES Also known as polar opposites. OPPOSITE EXTREMES Also known as polar opposites. CONFLICT Can be physical, or a clash of ideas / desires. CONFLICT Can be physical, or a clash of ideas / desires. ABERRATION Something that should be natural but has gone wrong. ABERRATION Something that should be natural but has gone wrong. TERROR Extreme fear. TERROR Extreme fear. AWE A sense of wonder (can be uplifting, or frightening). AWE A sense of wonder (can be uplifting, or frightening). THE SUPERNATURAL Whatever cannot be explained in the physical world. THE SUPERNATURAL Whatever cannot be explained in the physical world. DARKNESS May be literal or metaphorical. DARKNESS May be literal or metaphorical. ENTRAPMENT Can be physically luring someone into a place, situation or relationship, or mentally entrapping them into wrong ideas. ENTRAPMENT Can be physically luring someone into a place, situation or relationship, or mentally entrapping them into wrong ideas. IMPRISONMENT Physical. IMPRISONMENT Physical. OVER-REACHING Aiming too high, or for something you shouldn’t have. OVER-REACHING Aiming too high, or for something you shouldn’t have. MARGINAL Feeling or being on the edge of things either physically or emotionally / socially. MARGINAL Feeling or being on the edge of things either physically or emotionally / socially. PREDATORY Preying on others, either to physically harm them, or emotionally...
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...PHILIOSPHY OF NURSING This philosophy of nursing is assimilation of the author’s beliefs in regards of the metaparadigm through experience and understanding of knowledge. The author looks at the fundamental level, a theory which encompasses all or most theories. Attempts to view the theory as an interplay of energy, while looking at it in an atomic level. With the patient being the nucleus the primary structure and concentration of high energy while health and environment as different valence rings each holding electrons which are constantly moving in all possible directions all while orbiting around the nucleus. The space between the nucleus and the valence rings is nursing the spatial potential energy which unites the structure creating larger matter and ultimately the final product, the present material world (Seagar & Slabaugh, 2010). At the base of all matter is consciousness (Garon, 2011), therefore the universal fabric is conscious. A philosophy of nursing should be derived from laws that governing the universe and that is what the author attempts to do. Human Beings Human beings as defined by the writer are closely related to the understanding of human beings derived from humanistic nursing theorist specifically Martha E Rogers and Margaret Neumann. These theorist understood that human beings at a fundamental level are more than their biological makeup, they are consciousness. Sentient beings, or energy fields that are made up of patterns, holographic patterns...
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...Referring to the previous paragraph, Haigh persuasively argues that the Supremacy Bill which would provide freedom of theology as mentioned in previous paragraphs; was due to political rather than theological motives. Haigh clarifies the main purposes behind the Supremacy Bill, Chantries Act and the Treason Act 1533-1534. Haigh believes these Acts were devised due to political and economic reasons. This was economical because Henry VIII dissolved the monasteries this politically weakened the Catholic church as a political and fiscal institution, this ensured the transfer of property from the Church to the Crown, attached to monasteries were financial benefits. Nevertheless, hypothetically historians could interpret these acts as a way to...
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...Moral and Ethical Implications of Virtual Reality Every endeavor and ambition in life requires some form of decision making. The better we are at making good decisions, the more we can gain a favorable outcome from our endeavors and ambitions. Good decision making requires both moral and ethical fortitude. Virtual Reality (VR) in the psychological sense is an ambition to experience a world free of inhibitions and social judgments. Because this apparition of reality pays no immediate consequences for the mistakes we make in it, moral and ethical guidance is imperative. Does this virtual experience of reality impair ones judgment of actual reality? The ethical and moral questions raised by this phenomenon are very important to preserving our continuous perception of what is real and what isn’t. This section of the research paper is going to explore the moral and ethical equivalents of participating in virtual reality. Questions about impairment of moral and ethical compasses will be answered. Psychological representations and definitions of VR will further enhance our understanding of how VR can be either be a tool for social reform or a danger to moral and ethical aptitude. A Third State of Consciousness Imagination is a very powerful exercise for escaping pain or peril. It fuels creativity and builds hope. It can also unconsciously or consciously be used to exaggerate fear that either imprisons or save us from imminent threats and danger. The human...
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...Imagine living in a world where your soul mate is preapproved for you by the time you’re seventeen by the government. Where what you read, what you eat and how you live is already predicted. Quite hard to picture, huh? Ally Condie has succeeded in capturing this visionary society in her book Matched. She can reach a wide variety of audiences because it shows romance, risk taking, and the role of adapting to the image of what society expects from you. The author describes how by following your heart, by overriding your mind, can really influence every choice you make. The plot of Matched is typical, yet unique compared to other popular young adult novels. Cassia Reyes was stuck with the decision between trusting the government and trusting...
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...Discipline and Management: Different Yet Related Mary Keel Grand Canyon University: TCH-536 January 26, 2014 Comparison of Discipline and Management, and Behaviour and Misbehaviour Definitions Discipline denotes training or systematic instruction intended to produce a specific pattern of behaviour or character, especially training, which produces mental or moral character that adheres to a specific order or conduct. The term could also refer to the product of the training, which is controlled behaviour that results from self-control attained after disciplinary training. The term also denotes the act of punishing to enforce obedience or gain control (Marvin, 2014). Management is the coordination and organization of activities in a classroom in order to attain defined objectives and this involves controlling or dealing with students, processes and things in a manner that enables attainment of set goals and objectives (Marvin, 2014). Behaviour denotes observable activities or mannerisms in humans, which is an aggregate of responses to stimuli or input whether external and internal, voluntary of involuntary, covert or overt and conscious or subconscious. On the other hand, misbehaviour denotes conduct or actions that are incorrect, improper, inappropriate or unexpected of an individual based on their settings. Similarity of the Terms 1) Discipline and management are both control processes aimed at achieving specific objectives. On one hand, management...
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