Unstructured Reading Notes

  • Defense: Real-time Multi-Resolution Neural Networks for Hand Simulation, Mianlun Zheng (Advisor: Jernej Barbič)
    • from joint angle, simulate bone, tendon, muscle, vein, nerve, fascia, …
    • application: medical education, robotics, Metaverse, physical therapy (committee)
    • average (interpolate) 6 MRI scan of hand pose by calculating plastic strain & min energy function for equilibrium
    • pattern matching bad: need huge data; no anatomy (dumb)
    • tendon simulation: rod model; attach bone; emulate force from forearm; hook → tunnel to slide through
    • fascia: triangle mesh + cloth solver; fat: FEM simulation; nail: rigid point cloud in skin
    • high accuracy: < 1mm error against MRI
    • real-time neural net challenge: nets in graphics slow; real-world usage need < 1ms; existing libraries overlook small model
    • need: change level of detail (LOD) for Metaverse
    • animation: deform character to vertices
    • joint angle → linear blend skinning → net to reduce residue → real-time output
    • LOD support: more vertex each level; restriction vs prolongation to downsample & upsample
      • go up & down by level
      • each level each region (by unity construction) separate net → small net → efficient
    • further performance: reduce joint by perturbation simulation; PCA reduction for each region
    • hot cache performance: lower output dimension & faster than prior work; much faster on high level
  • Measuring context switching and memory overheads for Linux threads
    • Native POSIX Thread Library (NPTL) & futex several times faster than old Linux thread
    • bearable latency: on his i7-4771 in 2018, multicore context switching took ~1.5µs, same core switching ~2.5µs, launching thread ~5µs, launching process ~22.5µs
      comparison: memcpy 64 KiB took 3µs, Goroutine switching took 170ns
    • lazy memory: 8 MiB virtual via ulimit (VM), ~8 KiB resident (RSS) without touching stack
  • Optimal Protocols for Studying & Learning, Andrew Huberman
    • neuroplasticity apply during fast eye movement sleep
    • focus & alertness is how remember; sleep is prerequisite; meditation, NSDR are tool
    • testing help remember; test ASAP after exposure
      • best be open-ended, short answer, minimal prompt, require critical thinking
      • do not matter for memory if wrong
    • perceived familiarity hinder memory
    • gap effect: pause in talk greatly reinforce memory
  • ChatGPT from Scratch: How to Train an Enterprise AI Assistant • Phil Winder • GOTO 2023
    • post-GPT are decoder-only
    • logistic regression is often superb for domain-specific task
    • RLHF degrade performance
    • parameter-efficient fine-tuning (PEFT): use adapter alongside frozen model
    • quantization massively reduce RAM usage
    • Falcon-7B LLM: used in demo, said to have cleaned training data, open-source
    • fine tuning demo done on V100 in Colab
  • How Smartphones Shrink Our Brains
    • anticipation trump focus
    • habit to rely on tool kill memory
    • trying to split attention make though shallow
    • paper is better for thinking (I think large screen help)