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In addition to the 'pure vowels' (ones where the tongue positioning is fairly static) shown above there is also the set of vowel diphthongs. These are effectively long vowels during which the tongue moves to produce a definite change of quality during the sound. In phonetic transcription we usually use a pair of linked symbols for each diphthong - one indicating the quality of the sound at the start of the vowel, and the other indicating its quality as it ends. Examples of diphthongs are found in words like 'boy', 'hear', 'may', 'my
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Space Systems Laboratory Massachusetts Institute of Technology Optimization of Separated Spacecraft Interferometer Trajectories in the Absence of A Gravity-Well Optimization of Separated Spacecraft Optimization of Separated Spacecraft Interferometer Trajectories in the Interferometer Trajectories in the Absence of A Gravity Absence of A Gravity-Well Edmund M. Edmund M. Kong Prof David W. Miller David W. Miller
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1 Introduction Electrostatic thrusters (“ion engines”) are the best developed type of electric propulsion device, dating in conception to the ‘50’s,(1) and having been demonstrated in space in 1964 on a suborbital flight of the SERT I spacecraft(2). The early history
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United Nations Criminal Justice Information Network The United Nations Criminal Justice Information Network (UNCJIN)was created in 1989 pursuant to Economic and Social Council resolution 1986/11 of 21 May 1986, in which the Secretary-General was invited to establish, in cooperation with the United Nations institutes and other entities concerned, a global crime and criminal justice information network, including a mechanism for the centralizatio of inputs from non-
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The only practical way to accelerate something in free space is by reaction. The idea is the same as in air breathing propulsion (to push something backwards) but in rockets the “something” must be inside and is lost. Here is a revealing derivation of the thrust equation for vacuum:
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The result appears to be trivial, but it is not. Notice that the “velocity increment” ∆V is actually equal to the decrease in orbital velocity. The rocket is pushing forward, but the velocity is decreasing. This is because in a r-2 force field, the kinetic energy is equal in magnitude but of the opposite sign
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Chapter One Introduction Heat: Heat is a kind of energy, Which occurs in the transfer process. (the transferred energy contains the orderly work and disorderly heat) Energy: Concept of energy is used to specify the state of a system in thermodynamics Heat Transfer: kind of application science, is concerned with analysis of the rate of heat transfer taking place in system, or with the research on the heat-transfer reqularity
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Where Are W e Doing in This Chapter? After modeling consumers' choice set and his preference (represented by utility functions), we now put them together and model how he/she makes optimal choice. In mathematical terms, this is constrained maximization problem; In economics, this is rational choice problem
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Plant nitrogen 1.1 Uptake of N 1. N is required by plants in large amounts Most plant material contains 2-4%N and 40%C. 2. N is usually the limiting nutrient in unfertilized systems 3. Most n is taken up from the soil in the form of nht or no a small amount of NH3 can be absorbed through the leaves N2 can be used by legume plant via biological nitrogen fiXation
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Soil fertil Soil fertility is the characteristics of soil that enables it to Provide nutrients in adequate amounts in adequate time In appropriate balance for growth of particular plant(s)
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