Circuit parallele

Alexander G. E., Crutcher M. D., DeLong M. R. (1990). Basal ganglia-thalamocortical circuits parallel substrates for motor, oculomotor, prefrontal and limbic functions. Prog. Brain Res. 85, 119-46. 

This circuit could represent, for instance, a flashlight. Notice that there is only one path that can be taken by the current, thus we call this a series circuit. Parallel circuits offer the current more than one path and will have junctions where wires intersect. Of course, circuits, and hence circuit diagrams, can get very complicated. As such, rules have been developed to help simplify or reduce circuits to equivalent circuits containing fewer components. 

Sometimes the potentials are measured by the commutator method during which the electrolyzing current is suddenly interrupted and the value of the EMF of the cell shown by the brief reverse deflection of the voltmeter is quickly read. The voltmeter is connected in an electric circuit parallel with the electrodes. The deflection is caused by products accumulating at the electrodes in the course of electrolysis. The system acts for a short period as a galvanic cell. 

Alexander GE, Crutcher MD, DeLong MR. 1990. Basal gang-lia-thalamocortical circuits Parallel substrates for motor, oculomotor, prefrontal , and limbic functions. Pro Brain Res 85 119-146. 

The next stage in developing a model of localized chemiosmosis is to assume that there is a substantial resistance between the local circuit and the bulk phase [43,44]. One could devise hypothetical models in which one (Fig. 2.6c) or both (Fig. 2.6d) of the portions of the proton circuit parallel to the membrane were insulated from the bulk phases. It is important, however, to appreciate that such models still require the presence of a highly insulating phase separating the outward and return limbs of the proton circuit, with the addition of one or two further substantial resistances to protons. 

Figure 1. Impedance spectra (real vs. imaginary part) of an carbon aerogel and the corresponding equivalent circuit. The RC-circuit parallel to the double layer capacitance (circuit with dotted lines) corresponds to pseudocapacitances due to reversible redox-groups on the carbon surface [10]. The position x = 0 denotes the pore entrance of the cylindrical pore adjacent to the reference electrode. The corresponding frequencies are between 20 kHz and 8.25 mHz (region a to c).

Potential difference is measured in a unit called the volt. Voitage is potential difference. The higher the voltage, the more energy the electrons have. This energy is measured by a device called a voltmeter. To use a voltmeter, place it in a circuit parallel with the load you are measuring. 

This type of coil was prepared from copper cladded printed circuit board material by applying photolithographic techniques. The p.c. board material is available with difierent copper thicknesses and with either a stiff or a flexible carrier. The flexible material offers the opportunity to adapt the planar coil to a curved three dimensional test object. In our turbine blade application this is a major advantage. The thickness of the copper layer was chosen to be 17 pm The period of the coil was 100 pm The coils were patterned by wet etching, A major advantage of this approach is the parallel processing with narrow tolerances, resulting in many identical Eddy current probes. An example of such a probe is shown in fig. 10. 

The heart of an NMR spectrometer is the probe, which is essentially a tuned resonant circuit with the sample contained within the main inductance (the NMR coil) of that circuit. Usually a parallel tuned circuit is used with a resonant frequency of coq = The resonant frequency is obviously the most important probe... 

Wlien an electrical coimection is made between two metal surfaces, a contact potential difference arises from the transfer of electrons from the metal of lower work function to the second metal until their Femii levels line up. The difference in contact potential between the two metals is just equal to the difference in their respective work fiinctions. In the absence of an applied emf, there is electric field between two parallel metal plates arranged as a capacitor. If a potential is applied, the field can be eliminated and at this point tire potential equals the contact potential difference of tlie two metal plates. If one plate of known work fiinction is used as a reference electrode, the work function of the second plate can be detennined by measuring tliis applied potential between the plates [ ]. One can detemiine the zero-electric-field condition between the two parallel plates by measuring directly the tendency for charge to flow through the external circuit. This is called the static capacitor method [59]. 

In another type of measurement, the parallel between mechanical and electrical networks can be exploited by using variable capacitors and resistors to balance the impedance of the transducer circuit. These electrical measurements readily lend themselves to computer interfacing for data acquisition and analysis. 

The specific resistance of natural graphite crystals is ca Hem (room temperature) along the a axis parallel to the network basal plane. The resistance along the c axis (perpendicular to the basal plane) is ca 1 Q. The cja axis anisotropy ratio is, therefore, ca 10 . Screw dislocations within the crystal may short-circuit the current path parallel to the c axis and cause lower anisotropic ratios separation of planes may cause higher anisotropic ratios. 

A high throughput of instructions was achieved by pipelining the processing of instructions. The execution of instructions was divided into 12 suboperations that used 10 different circuits. When flowing smoothly, a new instruction could be taken every two clock periods (or 64 nanoseconds) and therefore up to six instructions were simultaneously in different phases of execution, and could be said to be in parallel execution (1). 

Design possibilities for electrolytic cells are numerous, and the design chosen for a particular electrochemical process depends on factors such as the need to separate anode and cathode reactants or products, the concentrations of feedstocks, desired subsequent chemical reactions of electrolysis products, transport of electroactive species to electrode surfaces, and electrode materials and shapes. Cells may be arranged in series and/or parallel circuits. Some cell design possibiUties for electrolytic cells are... 

Cone crushers can be operated in open circuit with capacities shown in Table 20-12, or in closed circuit in parallel with scalping screens for multistage size reduction, as Table 20-13 shows (the product sizes are not comparable). The feed should not contain more than... 

These are unidirectional and uncontrollablet static electronic devices and used as static switches and shown in Figure 6.14. A diode turns ON at the instant it becomes forward biased and OFF when it becomes reverse biased. By connecting them in series parallel combinations, they can be made suitable for any desired voltage and current ratings. Whether it is a transistor scheme or a thyristor scheme, they are used extensively where a forward conduction alone is necessary and the scheme calls for only a simple switching, without any control over the switching operation. They are used extensively in a rectifier circuit to convert a fixed a.c. supply to a fixed d.c. supply. 

Where three CTs for unrestricted or four CTs for restricted ground fault or combined O/C and G/F protections are employed in the protective circuit, the VA burden of the relay is shared by all the CTs in parallel and a normal VA CT may generally suffice. Such is the case in most of the protective schemes discussed in Sections 21.6 and 15.6.6(1), except for those employing only one CT to detect a ground fault condition, such as for a generator protection with a solidly grounded neutral (Figure 21.12). 

If there are N number of CTs connected in parallel, the magnetizing current will flow through all of them. In a CiF protection scheme all the three CTs of all the feeders being protected together will fall in parallel, while in case of a combined GF and phase fault protection scheme, only one third of these CTs will fall in parallel. The CT in the faulty circuit must be able to draw enough current to feed the magnetizing losses of all the CTs falling in parallel and the relay pickup current, The sensitivity of the differential scheme can therefore be expressed more appropriately as... 

This is a scheme introduced in the AVR circuit to adjust the reactive power (kVAr) of a machine during a parallel operation or when it is being used as a synchronous condenser. It prevents a reactive circulating current, l. ... 

---