Synchronization, sound

Post-synchronization Synchronizing sound and image is required when a soundtrack has been prepared independently from the image it is suppose to accompany. By modifying the time evolution of the sound track, one is able to re-synchronize sound and image. A typical example is dialogue post-synchronization in the movie industry. 

Delays of as little as a few milliseconds are what constitutes location information in the integration abilities of humans. Two synchronized sound sources placed before a listener, as is standard with stereo loudspeakers, appear to shift from being at the midpoint location to emanating toward the first in time source until delayed by 20-30 ms. Once the delay exceeds 20-30 ms the sources will diverge and be clearly discernible as two separately emanating sounds. 

The first issue concerns better synchronization of codes and standards development by the SDOs and model code organizations with the RD D needed to establish a sound technical and scientific basis for requirements incorporated in codes and standards. 

The field from a single neuron is far too weak to be detected outside the scalp with the present system. What Williamson is measuring is a field produced by ten thousand nerve cells working in synchronization. It sounds like an enormous number, but when one considers that 1 square millimeter of cerebral cortex—the wrinkled outer layer of gray matter, where various sensory and motor responses are coordinated and controlled—has about a hundred thousand neurons, the localizing capability of the MEG system becomes quite precise. 

The electric current from the playback head is amplified and sent to an audio speaker, which vibrates in synchronism with the varying current. The back-and-forth motion of the speaker creates pressure waves in the air. This causes the listener s ear drums to vibrate, producing the sensation of sound. 

A rival sound system, developed by General Electric and the Radio Corporation of America, put the soundtrack on the film itself, running it in a track next to the images. Since the pictures and their soundtrack were linked on the film, they could never get out of synchronization. This system was also easier to set up. After intense competition and many lawsuits over patent rights, this system beat the sound-on-a-disc system. 

Arterial bruit A systolic rushing sound synchronized with the heart beat indicates increased arterial blood flow. This often barely audible sound is easier to discern if one listens for arterial bruit and feels the patient s pulse at the same time. It is sometimes heard where aneurysm or stenosis is present in large arteries (e.g. coeliac artery, hepatic artery) as well as in arteriovenous malformations, highly vascularized liver tumours, pronounced acute alcohol hepatitis, 1-2 days after liver biopsy resulting from temporary arteriovenous fistula, or in twisted arteries in cirrhosis. It is seldom found in healthy persons. (10, 13, 44)... 

Ring modulation and synchronization go beyond this to create interactive effects, in which a parameter controlling one voice also affects the sound produced by a second voice. In both cases, the special effect is created by a difference in the frequencies (pitches) of the two voices. 

Ring modulation is a special type of synchronization in which overtones almost completely suppress the original tones. What you re left with is a sound composed chiefly of nonharmonic overtones. The results are often surprising and bear little if any resemblance to so-called natural sounds. 

When synchronization is selected, you ll hear the beating effect as the tone ascends in pitch and the two voices move in and out of phase with each other. Ring modulation creates a rich, spacey sound. Note that you can pause the tone with CONTROL while pressing a function key. As you ll hear, the sounds are far less exciting when both frequencies remain... 

As you ll discover by experimenting, these special effects work well with certain combinations, and poorly (or not at all) with others. Ring modulation works only when you set the carrier voice to the triangle waveform. Synchronization works with any waveform, but synchronizing any frequency with the noise waveform (a nearly random combination of many frequencies) doesn t accomplish much. The sawtooth and pulse waves often sound similar. 

The forerunners of the later standardized seasonal cniises started in May 1955 with synchronous measurements by the r/v Joh. L. Kruger and the r/v Magnetologe between the Fehmarnbelt and the Bornholm Basin. Finally, the programme of seasonal cruises had started in August 1957. It included about 50 fixed stations and comprised the combination of longitudinal and transversal sections between the Fehmarnbelt and the Bornholm Basin. More diurnal anchor stations each in the Fehmarnbelt and in the southern entrance of the Sound were included for investigations on temporal variabilities. The parameters measured were temperature, salinity, and oxygen at fixed depths. At some stations, current measurements were carried out from the anchored ship (cf. Section 3.2.1). 

Kevin Cuomo and Alan Oppenheim (1992, 1993) have implemented a new approach to this problem, building on Pecora and Carroll s (1990) discovery of synchronized chaos. Here s the strategy When you transmit the message to your friend, you also mask it with much louder chaos. An outside listener only hears the chaos, which sounds like meaningless noise. But now suppose that your friend has a magic receiver that perfectly reproduces the chaos—then he can subtract off the chaotic mask and listen to the message ... 

As discussed in Chapter 3, sound is a critical storytelling tool. Whether the sound is synchronized (directly related to the visuals—hearing the sound of a door opening when we see the door open) or is used asynchronously (in contrast to the visual), the overall pattern of the sound adds another dimension to the experience of the story. In this way, the sound can be used to support an aura of realism arising out of the visuals, or it can be used to create an alternate or multilayered view. 

We discuss now how the synchronization transition occurs, taking the applause in an audience as an example (experimental study of synchronous clapping is reported in [35]). Initially, each person claps with an individual frequency, and the sound they all produce is noisy.As long as this sound is weak, and contains no characteristic frequency, it does not essentially affect the ensemble. Each oscillator has its own frequency oJk, each person applauds and each firefly flashes with its individual rate, but there always exists some value of it that is preferred by the majority. Definitely, some elements behave in a very individualistic manner, but the main part of the population tends to be like the neighbor . So, the frequencies u>k are distributed over some range, and this distribution has a maximum around the most probable frequency. Therefore, there are always at least two oscillators that have very close frequencies and, hence, easily synchronize. As a result, the contribution to the mean field at the frequency of these synchronous oscillations increases. This increased component of the driving force naturally entrains other elements that have close frequencies, this leads to the growth of the synchronized cluster and to a further increase of the component of the mean field at a certain frequency. This process develops (quickly for relaxation oscillators, relatively slow for quasilinear ones), and eventually almost all elements join the majority and oscillate in synchrony, and their common output - the mean field - is not noisy any more, but rhythmic. 

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