Fuel assembly grids of pressurized water reactor strengthen the coolant mixing around fuel rod through mixing structure. The size and shape of mixing vane affects the mixing performance and flow resistance. This paper...
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Fuel assembly grids of pressurized water reactor strengthen the coolant mixing around fuel rod through mixing structure. The size and shape of mixing vane affects the mixing performance and flow resistance. This paper introduces the process and result of grid mixing performance optimizing design. Using CFD software, three dimensional flow field of three grid design schemes are analyzed and compared. The results show that the mixing performance of scheme 3 is better than that of scheme 1 and 2 in terms of the highest fluid temperature and the most difference in temperature. And mixing performance of scheme 1 and 2 is better than that of scheme 3 in terms of typical channel average temperature.
Because of text's properties, it's so difficult to find perfect algorithms of embedding watermark into text documents, when compared with other media. Nowadays, text watermarking technologies is far behind oth...
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Because of text's properties, it's so difficult to find perfect algorithms of embedding watermark into text documents, when compared with other media. Nowadays, text watermarking technologies is far behind other multimedia watermarking technologies such as images, audios, etc. A novel text digital watermarking technology based on graph theory is presented in this paper. Through changing its topology structures of a character or string, different figures are schemed out, which represent the same semanteme. Then those figures are mapped on graphs of graph theory, and the graphs or their properties should be correctly encoded in order to denote different watermarking information. The mathematic models of embedding and detecting watermarking are also described, and the experimental methods of robustness and visual influence, as well as the relative results are given. Finally, general rules of removing attack on text watermarking system is proposed, and the attack-resisting capability and methods of this text digital watermarking is analyzed in detail. According to the experimentation and analysis, the text watermarking technology has the following advantages: great capacity of watermarking, strong robustness, little visual influence and quite good attack-resisting capability. With this technology, it is more convenient to embed watermark into characters for ideograph languages such as Chinese and Korean, while it is suitable for embedding watermark into strings for alphabetic languages such as English and French.
A query-based local inverse modeling approach is proposed to compensate nonlinear power amplifiers (PAs) in orthogonal frequency division multiplexing (OFDM) systems. The PA is represented by the three-box model with ...
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A query-based local inverse modeling approach is proposed to compensate nonlinear power amplifiers (PAs) in orthogonal frequency division multiplexing (OFDM) systems. The PA is represented by the three-box model with a Wiener-Hammerstein structure. The inverse model of the PA is constructed based on the local modeling techniques, which can work as a predistorter (compensator) of nonlinear PA. Furthermore, a new look-up table (LUT) for constructing a predistorter of PA is also given to simplify the query-based nonlinearity compensation scheme (predistortion scheme). The effectiveness of the proposed scheme is validated by numerical simulation for a 64-ary quadrature amplitude modulation OFDM (64QAM-OFDM) transmission systems.
We compare two field demonstrations of SPECTS-OCDMA on an 80.8-km link and 150-km link using integrated, polarization independent arrayed-waveguide grating (AWG)-based encoders/decoders, an ultra-stable optical freque...
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We compare two field demonstrations of SPECTS-OCDMA on an 80.8-km link and 150-km link using integrated, polarization independent arrayed-waveguide grating (AWG)-based encoders/decoders, an ultra-stable optical frequency comb generator and a tunable dispersion-slope compensator.
In this article, a core fuel management program for hexagonal pressurized water type WWER reactors (CFMHEX) has been developed, which is based on advanced three-dimensional nodal method and integrated with thermal hyd...
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In this article, a core fuel management program for hexagonal pressurized water type WWER reactors (CFMHEX) has been developed, which is based on advanced three-dimensional nodal method and integrated with thermal hydraulic code to realize the coupling of neutronics and thermal-hydraulics. In CFMHEX, all these feedback effects such as burnup, power distribution, moderator density, and control rod insertion are considered. The verifica- tion and validation of the code system have been examined through the IAEA WWER-1000-type Kalinin NPP benchmark problem. The numerical results are in good agreement with measurements and are close to those of other international institutes.
An intranodal flux expansion nodal method (FENM) for solving static and transient neutron diffusion equations in hexagonal-z geometry has been developed, in which the flux distributions are expanded into a set of anal...
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ISBN:
(纸本)0894486977
An intranodal flux expansion nodal method (FENM) for solving static and transient neutron diffusion equations in hexagonal-z geometry has been developed, in which the flux distributions are expanded into a set of analytic basis functions and orthogonal second-order polynomials. In order to improve the nodal coupling relations, a new type of nodal boundary conditions is proposed, which requires the continuity of both the zero- and first-order moments of partial currents across the nodal surfaces. The numerical results for a series of benchmark problems demonstrate that FENM exhibits good accuracy and convergence.
China Integral reactor Plant (CIP) is a light water cooled, 300 MW power reactor under development by Chinese National Key laboratory of reactorsystemdesigntechnology. CIP features an integral reactor vessel that c...
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China Integral reactor Plant (CIP) is a light water cooled, 300 MW power reactor under development by Chinese National Key laboratory of reactorsystemdesigntechnology. CIP features an integral reactor vessel that contains the CRDM and major reactor coolant system components including reactor core, coolant pumps, once-through steam generators and pressurizer. This integral design approach eliminates the large coolant piping and large loss of coolant accident (LOCA), and thus provides with higher level of securities. This paper introduces the selection of CIP containment system, the design of containment, the determination of design pressure for containment and the calculation analysis of containment structure.
Backlight usually uses CCFL as light sources for the traditional LCD display. With the growing development of LED, it replaces CCFL gradually because of its advantage, such as durability, reliability, low-power and no...
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