Enjoy transportation and dynamic systems. Open Traffic Science. Views are my own.https://bsky.app/profile/jijunyi.bsky.socialhttps://bsky.app/profile/jijunyi.bsky.social/post/3m4oxpgvjk22eWhen I see posts claiming 15 or 20 papers for presentation at the TRB Annual Meeting, the peer pressure is undeniable. It's easy to get caught up in the race for quantity. But it begs the question: At what cost to quality?03 Nov 2025 02:24 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m4oxpgvjk22ehttps://bsky.app/profile/jijunyi.bsky.social/post/3m436ku6tnk2yWe may need tell the world a message: don't dream of RL for real-time signal control (in practice)! Multiple reasons...26 Oct 2025 05:34 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m436ku6tnk2yhttps://bsky.app/profile/jijunyi.bsky.social/post/3m2ptloqb6k2jPreliminary findings from the field experiments (conducted jointly with and led by JRC colleagues) on commercial L2+ automated vehicles show that their lane-changing behavior is surprisingly consistent. https://arxiv.org/abs/2508.0923308 Oct 2025 23:53 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m2ptloqb6k2jhttps://bsky.app/profile/jijunyi.bsky.social/post/3m2pteqirsc2jI highly recommend Prof. Benn Coifman’s talk. When discussing the fundamental relationship in traffic dynamics, let's first check how the data is generated. https://youtu.be/4oZM68VEkfE?si=wz6OefaPJiNdkY0L08 Oct 2025 23:49 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m2pteqirsc2jhttps://bsky.app/profile/jijunyi.bsky.social/post/3m2pt64iadc2jBack in 2015 (as an undergrad), I felt long-horizon traffic planning would not be the priority, we needed fine-grained, high-resolution data and research. Now, 10 years later, enabled by GenAI, we can finally move from coarse minute-level analysis down to the second level. tinyurl.com/trafficwavex08 Oct 2025 23:45 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m2pt64iadc2jhttps://bsky.app/profile/jijunyi.bsky.social/post/3m2pso4tohc2jAfter two years of effort, this study has now been accepted through peer review. In nowdays era of massive vehicle trajectory data, it is time to revisit how we analyze and understand traffic waves. I created a gallery with hundreds of traffic waves: trafficwaves.github.io. arxiv.org/abs/2409.00326 https://arxiv.org/abs/2409.0032608 Oct 2025 23:36 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m2pso4tohc2jhttps://bsky.app/profile/jijunyi.bsky.social/post/3m2psjbnpd22jI really enjoyed this paper, although I’m an outsider to Transportation Network Modeling. My main takeaway is clear: as more data becomes available, we should advance toward analyzing more complex networks, rather than continuing to benchmark solely on Sioux Falls. arxiv.org/abs/2508.06234 https://arxiv.org/abs/2508.0623408 Oct 2025 23:34 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3m2psjbnpd22jhttps://bsky.app/profile/jijunyi.bsky.social/post/3lyw7hrvz7s2jIt's great that we can post dataset and code link in the paper article info now!16 Sep 2025 01:51 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lyw7hrvz7s2jhttps://bsky.app/profile/jijunyi.bsky.social/post/3lw2bajlwsc27I'm always amazed by traffic research history. This is a highway test track at Ohio State University in 1969.10 Aug 2025 12:18 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lw2bajlwsc27https://bsky.app/profile/jijunyi.bsky.social/post/3lvlmxooii22oDon't chase for buzzword! First principle matters.04 Aug 2025 16:38 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lvlmxooii22ohttps://bsky.app/profile/jijunyi.bsky.social/post/3ltu74datvs2hTransportation is an application-driven field. Follow the first principle and solve the problems. We don't need more problems but we need more problem-solvers.13 Jul 2025 15:33 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3ltu74datvs2hhttps://bsky.app/profile/jijunyi.bsky.social/post/3ltf6zxfklk24https://www.rerite.org/awesome-rerite/07 Jul 2025 16:22 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3ltf6zxfklk24https://bsky.app/profile/jijunyi.bsky.social/post/3lt62ncvkhc2bOur 2nd Trajectory Data Camp at ITSC 2025! This year’s focus is on safety and human factors, and I wish to help drive the Vision Zero moonshot. https://i24motion.org/camp202504 Jul 2025 20:15 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lt62ncvkhc2bhttps://bsky.app/profile/jijunyi.bsky.social/post/3lrllnnwdbs2oLegacy NGSIM I-80 is now so real in Google Maps 3D view!!!14 Jun 2025 18:33 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lrllnnwdbs2ohttps://bsky.app/profile/jijunyi.bsky.social/post/3lqpsny264c2dI have to say, TRB is where I truly grew as a researcher.03 Jun 2025 17:24 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lqpsny264c2dhttps://bsky.app/profile/jijunyi.bsky.social/post/3lq3uptfg7227I’ll be at the TRB DATA conference as well! Just to mention, my advisor Dan Work has been my long-time supporter on reproducible research. And we’re actively contributing to open data in traffic science. [contains quote post or other embedded content]26 May 2025 19:08 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lq3uptfg7227https://bsky.app/profile/jijunyi.bsky.social/post/3lpfgcdsmjk2dIn memory of Peter Lax (1926–2025). I will dedicate myself to advancing the next chapter in the applications of hyperbolic partial differential equations in traffic flow dynamics. https://www.nytimes.com/2025/05/16/science/peter-lax-dead.html17 May 2025 20:51 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lpfgcdsmjk2dhttps://bsky.app/profile/jijunyi.bsky.social/post/3lotpdmos2k2yYou can be sad but please never be discouraged.10 May 2025 19:45 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lotpdmos2k2yhttps://bsky.app/profile/jijunyi.bsky.social/post/3loevjpe5ic2iMy first research grant! https://lab-work.github.io/blog/LFI25/04 May 2025 22:26 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3loevjpe5ic2ihttps://bsky.app/profile/jijunyi.bsky.social/post/3lo7zkn4bs22sAt the end of a paper [1] by Newell: Will we better in the next 50 years? [1] Newell, Gordon F. "Memoirs on highway traffic flow theory in the 1950s." Operations Research 50, no. 1 (2002): 173-178.02 May 2025 23:55 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lo7zkn4bs22shttps://bsky.app/profile/jijunyi.bsky.social/post/3lmnhgg33p22iImaging that we have a perfect, well-calibrated car-following model, what's the best thing you can do with it?12 Apr 2025 21:17 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lmnhgg33p22ihttps://bsky.app/profile/jijunyi.bsky.social/post/3lj7efbcibs2iit’s probably the best book I get this year!28 Feb 2025 02:30 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lj7efbcibs2ihttps://bsky.app/profile/jijunyi.bsky.social/post/3lj7e6vzi4s2bI need to improve my communication skills and enhance my ability to prioritize tasks. Things are just growing up.28 Feb 2025 02:26 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lj7e6vzi4s2bhttps://bsky.app/profile/jijunyi.bsky.social/post/3lhkjtvul7c2dIt can sometimes lead to a “publish and perish” scenario. [contains quote post or other embedded content]07 Feb 2025 02:16 +0000at://did:plc:olywe4ftyi7fcacicdzq25nr/app.bsky.feed.post/3lhkjtvul7c2d