REPARTO MODAL OPTIMO DEL TRANSPORTE TERRESTRE DE CARGA EN MEXICO. 1a ETAPA
Bibliographic record
Abstract
Este trabajo corresponde a la segunda etapa del estudio sobre reparto modal optimo del transporte terrestre de carga en Mexico, realizado por el Instituto Mexicano del Transporte (IMT) en 2014 y que se presento en la Publicacion Tecnica No. 413 de ese ano. El objetivo de esta segunda parte es analizar con mayor detalle los resultados de la primera etapa del estudio, a fin de mejorar el desempeno del modelo construido, asi como obtener datos mas recientes para hacer estimaciones de las asignaciones de los movimientos de carga en la red bimodal carretera-ferrocarril que se desarrollo en la primera etapa. Luego de describir los antecedentes del estudio de reparto modal en el capitulo 1 de introduccion, en el capitulo 2 se presenta un diagnostico del desempeno del modelo construido en la primera etapa, en el cual se examinan los resultados obtenidos en los escenarios de asignacion elegidos, estimando la precision de estos resultados con procedimientos de comparacion de los flujos pronosticados en el modelo contra flujos estimados de informacion de datos viales. Asimismo, se examina la consistencia de las matrices OD utilizadas, y se verifica de manera mas detallada la conexidad de la red bimodal construida en la primera etapa. En el capitulo 3 se revisa el indicador de reparto modal carretera-ferrocarril en otros paises: Estados Unidos, Canada y la Union Europea, para tener una panoramica del comportamiento de este indicador en paises industrializados, y se analizan los aspectos determinantes de la eleccion de modo en este contexto. El capitulo 4 muestra resultados del modelo ya ajustado en dos escenarios basicos de la red bimodal. Primeramente se muestran los resultados para las redes carretera y ferroviaria operando separadamente, sin posibilidad de transferir carga entre ellas. Luego, se muestran los resultados con la red bimodal tanto para el caso en que no hay transferencia de carga como para el caso en que si es posible transferir carga entre los modos. Los resultados obtenidos son consistentes con el criterio de los tiempos de recorrido en las distintas redes, en los cuales se considero la modelacion de congestion en la red carretera. Finalmente, en el capitulo 5 se resumen las conclusiones principales del trabajo, y se senalan algunas recomendaciones y posibilidades de trabajo futuro en el tema. Abstract: This work is the second stage of the study on optimal modal distribution of land freight transport in Mexico, developed by the Mexican Institute of Transport (IMT) in 2014 and published under Technical Publication number 413 in that year. The aim of this second part is to analyse in more detail the results of the first stage of the study, in order to improve the performance of the model developed and to gather more recent data to estimate assignments of cargo movements along the bimodal road-rail network developed on the first stage. After describing the background to the study of modal split in chapter 1 with an introduction, Chapter 2 shows a performance diagnosis of the model developed over the first stage, in which the results of the chosen assignment scenarios are examined, by estimating the accuracy of these results comparing the predicted flows in the model against data estimated from road counts. Also, the consistency of the OD matrices used is examined and the connectedness of the bimodal network built on the first stage is examined with more detail. In chapter 3 the road-rail modal share indicator in other countries is reviewed: United States, Canada and the European Union, in order to get an overview of the behaviour of this indicator in industrialized countries. The determinant for modal choice is examined in this context as well. Chapter 4 shows results with the adjusted model in two basic scenarios on the bimodal network. Firstly results are shown for the highway network and the rail network separately, without cargo transfer between both networks. Then, results on the bimodal network are shown, both without cargo transfer and when cargo transfer is allowed. The results obtained are consistent with the travel time criterion used in modelling, including congestion aspects of highway flows. Finally, Chapter 5 summarizes the main conclusions, pointing out some recommendations and prospects for future work on the subject.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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".