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991.
Multiterminal source encoding with one distortion criterion   总被引:1,自引:0,他引:1  
The authors unify earlier investigations concerning the encoding of two correlated sources {Xk}, {Yk } by means of separate encoders. Decoding is done by a single decoder which receives the outputs from both encoders. The reconstruction of {Xk} is required to be perfect in the usual Shannon sense. The authors determine the admissible rate region R (D), where D is the distortion of the reconstruction of {Yk}. The binary Hamming case is investigated explicitly  相似文献   
992.
The effects of receiver misplacement and the trough pointing towards the sun on the concentration characteristics of a composite parabolic trough are discussed. Results from some numerical calculations are presented graphically and discussed.  相似文献   
993.
A method has been proposed for measuring local heat transfer coefficient. The method uses the change of wet surface temperature by radiation heating and can be applied to the isothermal condition and the large variation of the local heat transfer coefficient along the surface of a body. The present method is based on the heat balance equation, which expresses a simple relationship between humidity and wet-bulb temperature. An experiment was devised to measure the local heat transfer coefficient of a flat plate. The results confirmed the effectiveness of the present method to measure the local heat transfer coefficient with reasonable accuracy.  相似文献   
994.
995.
The scientific community and general public can best take advantage of the benefits of 3D digital reconstructions if they are stored in a Web-accessible, easy-to-access database. We describe MorphologyNet/sup /spl copy// a Web-based digital library of realistic, 3D interactive and customizable images of anatomy currently in development at the University of Missouri-Rolla.  相似文献   
996.
997.
The codeword error rate (WER) performance of noncoherent frequency-shift keying with soft decision decoding of block codes using Chase's second algorithm (1972) is investigated in a Rayleigh fading channel. The received signal envelope is sampled and used as channel measurement information. The theoretical upper and lower bounds of the WER are derived, assuming independent Rayleigh envelope samples in a received block. When the Golay (23, 12, 7) code is used, soft decision decoding with 6-bit error correction capability (3-bit error and 3-bit erasure) requires an average signal-to-noise power ratio about 5 dB lower than that for minimum distance decoding with 3-bit error correction to obtain a WER=10-3. The effects of bit interleaving on the WER performance when fading envelope variation is slow compared to the bit rate are investigated through computer simulations  相似文献   
998.
999.
A design method for tuning of multivariable PI-controllers for possibly unknown linear time-invariant delay-differential systems is presented. The plant is assumed to be stable with input and output delays and subject to step disturbances. The multivariable PI-controller may be tuned with the aid of open-loop step responses. The stability and robustness of the control law is discussed and an example is given to show the applicability of the controller.  相似文献   
1000.
If technologies for decentralised sanitation and reuse (DESAR) and for natural stormwater management should at least partially replace existing systems, then intensive reconstruction work becomes essential. A conversion can only be realised successively over a long period due to high construction and financial expenses and requires new strategies. This paper presents the development and practical implementation of a mathematical tool to find an optimised strategy for the realisation of alternative and more decentralised drainage and sanitation concepts in existing urban areas. The succession of construction measures (e.g. the implementation of decentralised greywater recycling) for the whole period of consideration is determined based upon a mathematical optimisation model on the condition that the favoured future state is known. The model describes the complex interdependencies of the urban water and nutrient cycle and enables the minimisation of both financial efforts and ecological impacts on the way toward the future state. The results of the implementation for a rural area in Germany show that the mathematical optimisation is an adequate instrument to support decision-making processes in finding strategies for the realisation of sustainable urban water management.  相似文献   
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