Analysis of Brownian Dynamics and Molecular Dynamics Data of Unentangled Polymer Melts Using Proper Orthogonal Decomposition
Bibliographic record
Abstract
Abstract A non‐linear Brownian dynamics (BD) model based upon the Rouse model is developed for unentangled polymer melts. The essence of the model is that it includes an equilibrium spring length b , a non‐linear force term that is not present in the equation of motion of the Rouse model. The equation of motion is solved numerically with the technique of proper orthogonal decomposition (POD) to obtain the dynamics information. To illustrate that the BD model can be readily implemented on polymers with different molecular structures, it is applied to polyethylene with linear, ring, and star structures. For comparison purpose, the corresponding molecular dynamics (MD) simulation is also carried out on molecules with the same sizes ( N = 30–73). To characterize the dynamics, time correlation functions of the end‐to‐end vector, the m ‐to‐ n vector, and the arm vector of the linear, ring, and star polyethylene are determined respectively. It is found that the longest relaxation times (τ 1 s), the relaxation times of the vectors (τ v s), as well as zero‐shear viscosity (η 0 s) obtained from the BD and MD simulations agree well with each other. The time correlation functions can be reasonably described using the eigenmodes.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".