Programmable electronic synthesized capacitance

A predetermined and variable synthesized capacitance which may be incorporated into the resonant portion of an electronic oscillator for the purpose of tuning the oscillator comprises a programmable operational amplifier circuit. The operational amplifier circuit has its output connected to its inverting input, in a follower configuration, by a network which is low impedance at the operational frequency of the circuit. The output of the operational amplifier is also connected to the noninverting input by a capacitor. The noninverting input appears as a synthesized capacitance which may be varied with a variation in gain-bandwidth product of the operational amplifier circuit. The gain-bandwidth product may, in turn, be varied with a variation in input set current with a digital to analog converter whose output is varied with a command word. The output impedance of the circuit may also be varied by the output set current. This circuit may provide very small ranges in oscillator frequency with relatively large control voltages unaffected by noise

The relationship of site to transplantability

Thesis (M.A.)--Boston Universit

The Kai Ba Lidai Shiji 开吧历代史记 an Autonomous History of the Chinese Community of Batavia/ Jakarta in the VOC Period

This essay critically examines the Kai Ba Lidai Shiji (Annals of Batavia), a Chinese history of Batavia which was written by an anonymous Chinese author around 1794 as part of the rather large corpus of Chinese archival sources about the history of the Chinese community of Batavia/Jakarta. A short introduction about earlier authors who have dealt with the text is followed by comments on the composition, structure and historical value of this unique urban history

Low phase noise oscillator using two parallel connected amplifiers

A high frequency oscillator is provided by connecting two amplifier circuits in parallel where each amplifier circuit provides the other amplifier circuit with the conditions necessary for oscillation. The inherent noise present in both amplifier circuits causes the quiescent current, and in turn, the generated frequency, to change. The changes in quiescent current cause the transconductance and the load impedance of each amplifier circuit to vary, and this in turn results in opposing changes in the input susceptance of each amplifier circuit. Because the changes in input susceptance oppose each other, the changes in quiescent current also oppose each other. The net result is that frequency stability is enhanced

Reflection oscillators employing series resonant crystals'

A reflection oscillator is provided which employs an active device operated in its roll-off region and two resonant circuits. For an oscillator employing a bipolar transistor, the emitter is connected to a series resonant capacitor-crystal network and the base is connected to an L-C tank circuit with the transistor being operated in the roll-off region of its gain versus frequency curve. This will provide a very high frequency of operation with a relatively inexpensive, low frequency, active device. These oscillators are easily tuned, stable, and require little dc power

The World as a Hologram

According to 't Hooft the combination of quantum mechanics and gravity requires the three dimensional world to be an image of data that can be stored on a two dimensional projection much like a holographic image. The two dimensional description only requires one discrete degree of freedom per Planck area and yet it is rich enough to describe all three dimensional phenomena. After outlining 't Hooft's proposal I give a preliminary informal description of how it may be implemented. One finds a basic requirement that particles must grow in size as their momenta are increased far above the Planck scale. The consequences for high energy particle collisions are described. The phenomena of particle growth with momentum was previously discussed in the context of string theory and was related to information spreading near black hole horizons. The considerations of this paper indicate that the effect is much more rapid at all but the earliest times. In fact the rate of spreading is found to saturate the bound from causality. Finally we consider string theory as a possible realization of 't Hooft's idea. The light front lattice string model of Klebanov and Susskind is reviewed and its similarities with the holographic theory are demonstrated. The agreement between the two requires unproven but plausible assumptions about the nonperturbative behavior of string theory. Very similar ideas to those in this paper have been long held by Charles Thorn.Comment: SU-ITP-94-33, phyzzx, 33 pages and 5 figures (Some typos fixed and one reference added.

New parameterization of the resonant production amplitudes near an inelastic threshold

New formulae for the resonant scattering and the production amplitudes near an inelastic threshold are derived. It is shown that the Flatte formula, frequently used in experimental analyses, is not sufficiently accurate. Its application to data analysis can lead to a substantial distortion of the effective mass spectra and of the resonance pole positions. A unitary parameterization, satisfying a generalized Watson theorem for the production amplitudes, is proposed. It can be easily applied to study production processes, multichannel meson-meson interactions and the resonance properties, including among others the scalar resonances a0(980) and f_0(980).Comment: 4 pages, 1 figure, contribution to MESON 2008, Tenth International Workshop on Meson Production, Properties and Interaction, 6-10 June, Krakow, Poland, to be published in International Journal of Modern Physics

PV large systems project

Near term photovoltaic central-station markets are analyzed. Cost effectiveness of photovoltaic plants is determined in terms of reduction of oil consumption. The breakeven photovoltaic system cost vs oil-steam power generation is given. The value of photovoltaic power plants in Southern California and in Los Angelos is given in terms of fuel savings and capacity value. The potential value of third party financing, facilitated by Federal and state tax incentives is analyzed

Metacognition and recovery style in psychosis

Section A reviews the literature which has investigated variables found to relate to recovery style in individuals with psychosis. Studies exploring the attachment, self-esteem, depression and executive functioning are evaluated and conclusions drawn. Section B reports the findings of an empirical study investigating the relationship between metacognition, recovery style, anxiety and depression in a community sample of individuals with psychosis. Objective; Research has shown that individuals with psychosis will either integrate their experience of psychosis or seal the experience over. Little is known about what leads to these different styles of recovery but poor attachment, depression, low self-esteem and poor executive functioning have been linked to a sealing-over style. This study hypothesised that sealing is linked to unhealthy metacognitive beliefs and also to higher levels of anxiety and depression. Method; Forty-three participants with a diagnosis of psychosis were recruited. They completed the Metacognitions Questionnaire-30, Recovery Style Questionnaire and the Hospital Anxiety and Depression Scale. Results; Correlational analysis revealed that only one facet of metacognition linked to sealing over; this being positive beliefs about worry and this was maintained when the effects of anxiety and depression were accounted for. Contrary to the hypothesis, recovery style did not correlate with anxiety or depression but unhealthy metacognition was linked to both anxiety and depression. Conclusions; The findings of this study suggest that a sealing-over recovery style may be linked to one specific area of metacognitive dysfunction. They also cast doubt on previous theories which link low mood to a sealing-over style. Limitations of this study include its cross-sectional design. Future research which expands on these findings is encouraged and longitudinal research is particularly called for. Section C provides a critical evaluation of the project, answering four questions regarding what the author has learnt from the study, what might have been done differently, how the study might affect the author‟s clinical work in future and possible future research directions