Page 110 - ITU Journal Future and evolving technologies Volume 2 (2021), Issue 4 – AI and machine learning solutions in 5G and future networks
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ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 4




          However,  traditional  BFS  cannot  visit  the  visited   In order to further improve the prediction accuracy,
          node, and there is a situation in which the node is   Zezhong Feng tried to add more features to improve
          visited  multiple  times  in  the  simulation  data.  To   the traffic forecast model. In the time dimension, we
          solve this problem, Lin Xi modified the BFS search   add the two features of the day’s weather and the
          status  part  so  that  the  improved  algorithm  can   weekend  to  make  it  have  traffic  and  weekend
          repeatedly visit the node and adapt the search of the   features; in the space dimension, we add the node
          link set.                                            traffic  at  a  certain  distance  around the  node  as  a
                                                               feature, and we analyze that it is within a certain
                                                               range (tentative 2 Km) where nodes have an impact
                                                               on the node traffic of the current link, and such node
                                                               traffic is added to features.
                                                               Zezhong Feng’s experimental results indicate that:
                                                               By  adding  weather  features,  the  average  forecast
                         Fig. 8 – Improved BFS
                                                               accuracy of the model is increased by 0.4%;
          For  TFM,mainstream  time  series  prediction
          algorithms  include  multiple  linear  regression,   by adding the features of working day/off day, the
          Autoregressive differential Moving Average (ARIMA)   average forecast accuracy of the model is increased
          and  Long-Short-Term  Memory  network  (LSTM)        by 1.6%;
          model [7]. By analyzing the characteristics and data   by adding the traffic chrematistics of surrounding
          of this research, the influence between the data is   nodes, the average forecast accuracy of the model is
          almost  non-linear.  Among  the  above  prediction   increased by 1.8%;
          models, the LSTM model is designed with a special
          structure  to  memorize  and  filter  the  changes  in   after all three features were added, the average
          traffic on the time scale. Therefore, we choose the   forecast accuracy of the model increased from
          LSTM  recurrent  neural  network  model  for         91.7% to 95.3%.
          prediction  to  meet  the  requirements  of  this
          prediction scenario.












                         Fig. 9 – LTSM adopted                                       Fig. 11
          Zezhong  Feng  believes  that  the  bottleneck  for   2.5  Optimization strategy
          improving the accuracy of traffic forecasting is that   In terms of Topology Optimization Strategy (TOP),
          there are few samples and few influencing factors,   Zhouwei Gang proposed an optimization strategy of
          many nodes of different types, so the model is in two   "(ultra-low)*3". First calculate the utilization rate of
          layers  to  reduce  overfitting  and  under-fitting.  We   all links and the average value of the entire network,
          build a model for each node and increase the flow    and  set  a  threshold  to  divide  all  links  into  three
          information carried by each neuron from 1 to 24, so   categories:  overload,  low  load  and  normal.  The
          that the model can fit more flow changes. In the end,   overload links are processed first, and then the low-
          the average accuracy of TFM increased from 91.7%     load links are processed. After finishing, adjust the
          to 95.3%.                                            threshold value, do it twice again, and finally obtain
                                                               the  optimized  topology  by  completing  three
                                                               threshold adjustments.






                        Fig. 10 – Improved input                        Fig. 12 – Topology optimization strategy




          94                                 © International Telecommunication Union, 2021
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