MétaCan
Menu
Back to cohort
Record W3085604542 · doi:10.1021/acs.est.0c01670

Optimizing the Use of a Constrained Resource to Minimize Regional Greenhouse Gas Emissions: The Case Study of Slag in Ontario’s Concrete

2020· article· en· W3085604542 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.
fundA Canadian funder is recorded on the work.
aboutThe title or abstract carries a Canadian signal from the geographic lexicon.

Bibliographic record

VenueEnvironmental Science & Technology · 2020
Typearticle
Languageen
FieldEngineering
TopicRecycled Aggregate Concrete Performance
Canadian institutionsUniversity of Toronto
FundersNatural Sciences and Engineering Research Council of CanadaGovernment of CanadaBASF
KeywordsGreenhouse gasPortland cementEnvironmental scienceGround granulated blast-furnace slagSlag (welding)Lead (geology)Life-cycle assessmentNatural resource economicsWaste managementEnvironmental engineeringProduction (economics)EngineeringCementEconomicsFly ash

Abstract

fetched live from OpenAlex

Green policies currently incentivize concrete producers to replace portland cement with industrial byproducts to reduce their greenhouse gas (GHG) emissions. However, policies are based on attributional life cycle assessments (LCAs) that do not account for market constraints and consider byproducts either available burden-free to the user (cutoff approach) or partially responsible for the emissions generated in the upstream processes (allocation). The goal of this study was to investigate whether these approaches (and incentives) could lead to a mismanagement of byproducts and to suboptimal solutions in terms of regional GHG emissions. The use of ground granulated blast-furnace slag (GGBS) in Ontario was studied, and an optimization model to find the least GHG-intense way of using GGBS was developed. Results showed that producers should replace 30 to 40% of portland cement in high-strength concrete to minimize the regional GHG emissions associated with concrete. However, traditional LCA approaches do not suggest this solution and are estimated to lead to up to a 10% increase in concrete GHG emissions in Ontario. The substitution method, which assigns emissions or credits to byproducts based on emissions associated with the products they may displace, can yield decisions consistent with the regional emission optimization model. A revision of current policies is recommended to include market constraints.

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.

Full frame distilled prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.528
Threshold uncertainty score0.545

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.001
Scholarly communication0.0000.000
Open science0.0010.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

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.

Opus teacher head0.031
GPT teacher head0.214
Teacher spread0.183 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it