Why analytical study?

“Given that evaluating Q(nc, nb) in (1) for many pairs of nc and nb is tedious, we propose instead using an analytical function that approximates the 3D-vMFD in Fig. 1(a). ” [1]

“Nevertheless, by comparing the parameters of the two models, no physical interpretations can be made. In Section 3 we provide an analytical derivation
to estimate P(nc, nb) from Q(nc, nb), without the need of curve-fitting, which unveil interesting properties of network traffic flows.” [1]

[1] A three-dimensional macroscopic fundamental diagram for mixed bi-modal urban networks.

The philosophy you’ve learnt from OR.

Equations give you insights more than clearly

Be a professor?


  • Freedom (you don’t appreciate because you never leave campus by far; see amazon’s ad);

  • Allow you keep improving;
  • It is stable (not because it’s stable, but you have every choice to leave or stay).
  • Consulting companies (e.g. Cambridge Automatic) confine your research interest.
  • In industry, you may loose your advantages to 25s’ boys when you are at your 35.
  • Establishing your lab is similar to a start-up business, which may be struggling but a lot of fun, a meaning life.
  • Cont’d


  • Struggling, struggling, struggling, especially at the beginning as an AP.

Why analytical study?

“Given that evaluating Q(nc, nb) in (1) for many pairs of nc and nb is tedious, we propose instead using an analytical function that approximates the 3D-vMFD in Fig.1. ” – 3D MFD in mixed bi-modal urban network (Nikolas Geroliminis).

The philosophy you have learnt from OR.


Finished my work at 10pm, then heading home, somehow I wish to eat some Qincai. The bus passed my house but I didn’t get off. Instead I went directly to the market and bought some. Then wait the bus (it’s a long time waiting), steal into my house, drop my bag, I started my cooking. After finished it, almost midnight… I sit at table and tears almost there. It’s so so delicious!! So delighted!

You want to know why I behave so … because it is so hard on my research and classes these days, and I find one way out is to cook so that at least I could receive some sense of achievement there. 😁😁

I found that my interest changes a lot, quickly. I used to enjoy reading after tired from work. Now cooking… It may not a good thing, as they always say so bad to be 3min enthusiasm. But it is better using 3min to complete 70percentage than 5min completing 50persentage. Isn’t it?


Uncertainties in our daily lives

Cloudy in the morning but fantastic afternoon! The pleasure of daily life lies in the uncertainties there. Maybe the same for the research. I was confident with one proposal but it turns out a rejection from my advisor… Funny.
What if you wake up with a sunny weather? What if your research goes steadily without a wave?
Say thank you! See you tomorrow/next week with a smile on the face.


To ask a right question is harder than to answer it. — Georg Cantor

Everyone know how to create figures, so what? Just check your we chat official account, everyone is showing off their plots. Boring.

Abstractness is the price of generality. So if your research question is too concrete and clarified, it may not a good thing – it means the lost of generality.


You are at your first year and got a first authored paper! So do something risky. Do not just try to publish more. –sb’s boss.

Everyone creates plots. Do not plot meaningless. That kind of work is trivial. Think more and deeper. –CC

Application works are boring, only adding your workload. Theory ones are more interesting and time-worthy. Your boss is doing the right thing. –sbP