Codes single-channel

Researchers have oscillated between emphasizing specificity of neurons ( labeled lines ) and responses to a spectrum of tastants by one cell. More recently, patterns of activation of a number of sensory cells are favored for coding specific taste sensations (Smith and Margolskee, 2001). Neural distinction of different tastes requires simultaneous activation of different cell types. The brain receives a single channel of information, simply bitter for a number of different compounds. 

Intensity Coding/Coupling. The intensity coding/coupling tool combines channel pairs or multiple channels and transmits only a single channel plus directional information for parts of the spectrum. 

The CDA analysis code development and validation studies have continued extensively SAS4A for CDA s initiating phase and SIMMER-III for the transition phase. For SAS4A, tmder collaboration with KfK and CEA, a reference code version REF-94 has been developed for common use in the future. A special single channel code PAPAS-2S, which models detailed fuel pin mechanics, is also being elaborated through CABRI analyses. The fluid-dynamics system in SIMMER-III has approached its completion /and the coupling with the neutronics is underway. A code assessment... 

It was evident that the accurate prediction of reactivity levels and power distribution for such a complicated loading would provide a severe test of the PATRIARCH computer codes (refs 2, 3)- In many cases, it has been necessary to use the SOLOMON synthesis code to obtain an adequate representation. This combines the AIMAZ XY-reactor physics model with the CUSH multi-channel primary circuit representation and the TIRAZ coupled nuclear-thermal-hydraulic single channel model. 

The change of cross flow within a subassembly may occur during transients. The MCST may change from the result of the single-channel calculation. A transient subchannel analysis code was developed and the safety analysis of a Super LWR was carried out [70]. The temperature rises from the steady state value are about 20°C at the abnormal transients and about 130°C at accidents. The maximum values still stay below the MCST criteria for transients and accidents. The development and application of the transient subchannel analysis code are sununarized in Sect. 6.8. 

One-dimensional bum-up and two-dimensional R-Z core calculation procedures for the fast reactor are found in refs. [108,109]. The LOCA analysis code, SCRELA was described in ref. [110]. The procedure for a simplified PSA is also described there. The single channel thermal-hydrauUc calculation code SPROD, the two-dimensional coupled core calculation scheme of the thermal spectram reactor with water rods and transient and accident analysis code at supercritical-pressure, SPRAT are described in ref. [111]. 

The plant analysis code developed at the University of Tokyo for the Super LWR with downward flow type water rods is used here. The thermal hydraulic analyses are carried out by using the one-dimensional single-channel model of the fuel... 

In the linear approach, the steady-state parameters are required as initial conditions for the evaluation of system stability, and they are calculated by the plant analysis code developed for the Super LWR, considering the effects of water rods on the coolant channels. The fuel channel is axially discretized into meshes of equal length, and the fuel and coolant properties are assumed uniform within each mesh. The one-dimensional single-channel single-phase conservation equations are solved for each axial mesh in the fuel channel and in each water rod, starting from the core inlet to the core outlet. The core inlet coolant temperature and mass... 

Since the transient subchannel analysis code does not have the functions prepared in typical system analysis codes, several parameters are taken from the calculation results by the single channel safety analyses performed in Sect. 6.7. These parameters are the flow rate, temperature and pressure at the inlet of the hot fuel assembly, and the relative power. The radial and axial power distributions are assumed not to change with time. This is reasonable because the reactivity is not locally changed at the flow decreasing events. 

The time profiles of the increase in the maximum cladding surface temperature (AMCST) are shown in Fig. 6.64. The peak values of Cases 1 and 2 are almost equal to that calculated by the single channel code while that of Case 3 is higher than the result by the single channel code by about 25°C. 

The fuel rod design criteria except those of collapse and creep collapse are investigated with single channel thermal hydraulic analysis and fuel rod thermomechanical analysis. Design criteria are assessed by the FEMAXI-6 code as is also used for the Super LWR (see Chap. 2). Figure 7.12 shows the interaction of the fuel... 

The third element is a three-letter code indicating the type of front end, shell, and rear end, in that order. For example, a fixed tubesheet exchanger (the tubesheet does not expand and contract as it heats and cools) with removable channel and cover, single-pass shell, 23K-in, inside diameter with tubes 16 ft long is denoted as SIZE 23-192 TYPE AEL. 

A much better time resolution, together with space resolution, can be obtained by new imaging detectors consisting of a microchannel plate photomultiplier (MCP) in which the disk anode is replaced by a coded anode (Kemnitz, 2001). Using a Ti-sapphire laser as excitation source and the single-photon timing method of detection, the time resolution is <10 ps. The space resolution is 100 pm (250 x 250 channels). 

Error resilience Depending on the architecture of the bitstream, perceptual coders are more or less susceptible to single or burst errors on the transmission channel. This can be overcome by application of error-correction codes, but with more or less cost in terms of decoder complexity and/or decoding delay. 

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