Shiraz University
Iranian Journal of Science and Technology Transactions of Electrical Engineering
2228-6179
28
3
2013
02
17
Variable length to block coding
389
393
EN
10.22099/ijste.2013.1037
We treat the problem of encoding the outputs from an information source, and the class of encoding schemes considered is restricted to those in which each output from the source is encoded as a separate, uniquely decodable codeword. We present a uniquely decodable scheme in this class which minimizes the ensemble average length of the transmitted message. The efficiency of this method in some cases is higher than conventional methods like block coding (in this paper we call it "block to variable length coding" relative to the title of the paper) by using the Huffman method. Although the efficiency of the encoding scheme can be improved by using the variable length to variable length technique, this topic is not pursued
Block coding,variable length coding,prefix codes
https://ijste.shirazu.ac.ir/article_1037.html
https://ijste.shirazu.ac.ir/article_1037_d41d8cd98f00b204e9800998ecf8427e.pdf
Shiraz University
Iranian Journal of Science and Technology Transactions of Electrical Engineering
2228-6179
28
3
2013
02
17
An artificial intelligent system for traffic forecasting in virtual stations of highways
395
400
EN
10.22099/ijste.2013.1038
Traffic data and statistics (as density) are among the most important and crucial tools for the study of traffic, optimization of urban transportation and traffic programming. For this reason, the Tehran Traffic Control Company (<em>TTCC</em>) has built some data acquisition stations in various highway locations in Tehran. There are <em>TTCC</em> 10 data acquisition stations in use at the moment and more stations are to be designed and implemented in the future. The implementation of each station consists of three stages: field study, equipment installation and setting up magnetic rings, which require a long design time and high cost for data acquisition equipment, as well as induction sensors and heavy work load for installing magnetic rings. The final stage comes with many problems, particularly in highways, and needs high safety standards. Considering problems such as cost and safety of the implementation, the design of virtual stations seem necessary. A virtual station does not exist physically, but it can calculate traffic data. This proposal is known as Spatial Forecasting, which provides forecasting in space dimension using statistical data from present stations. The present article introduces an intelligent neuro-fuzzy structure which is trained over statistical traffic density data of the Modarres highway and is used for spatial forecasting. Results of simulation show that a neuro-fuzzy network can be used successfully for this purpose
Neuro-fuzzy network,virtual station,spatial forecasting,traffic data and statistics
https://ijste.shirazu.ac.ir/article_1038.html
https://ijste.shirazu.ac.ir/article_1038_d41d8cd98f00b204e9800998ecf8427e.pdf