{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T06:58:48Z","timestamp":1781161128800,"version":"3.54.1"},"reference-count":68,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T00:00:00Z","timestamp":1780963200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Beijing Social Science Foundation Project","award":["25BJ03189"],"award-info":[{"award-number":["25BJ03189"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Systems"],"abstract":"<jats:p>Port integration reforms constitute an important institutional arrangement for promoting green development in the shipping sector and achieving China\u2019s carbon peaking and carbon neutrality goals. Assessing their carbon-mitigation effect is crucial for improving the governance framework of port integration and promoting high-quality port development. Using panel data for 55 Chinese port cities from 2011 to 2022, this study exploits the staggered implementation of port integration strategies as a quasi-natural experiment and applies a multi-period Difference-in-Differences (DID) approach to estimate their effects on port carbon emissions. The results indicate that port integration reforms significantly reduce carbon emissions, implying that integration acts as a substantive driver for low-carbon transformation. Heterogeneity analysis shows that the emission-abatement effect is stronger for ports outside the Yangtze River Economic Belt, coastal and southern ports, large-scale and small-scale ports, regions with weaker environmental regulation, cities with more advanced industrial structures, and major national hub ports. In contrast, the policy effect is relatively muted for medium-sized ports, highly regulated regions, cities with less advanced industrial structures, and non-core hub ports, where port integration delivers merely weak marginal emission reduction effects. Further mechanism tests reveal that green technological innovation plays a certain mediating role. This study contributes to the literature by providing dynamic causal evidence on how port governance reforms shape green development outcomes. It also offers policy implications for designing differentiated port integration strategies that align with regional development conditions and national low-carbon transition objectives.<\/jats:p>","DOI":"10.3390\/systems14060662","type":"journal-article","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T05:50:58Z","timestamp":1781157058000},"page":"662","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Accelerator or Not? The Impact of Port Integration Reform on Carbon Emissions with Evidence from Chinese Ports"],"prefix":"10.3390","volume":"14","author":[{"given":"Yuxin","family":"Dai","sequence":"first","affiliation":[{"name":"School of Economics and Management, Beijing University of Chemical Technology, Beijing 100029, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaxin","family":"Suo","sequence":"additional","affiliation":[{"name":"School of Economics and Management, Beijing University of Chemical Technology, Beijing 100029, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2695-7858","authenticated-orcid":false,"given":"Jinpei","family":"Li","sequence":"additional","affiliation":[{"name":"School of Economics and Management, Beijing University of Chemical Technology, Beijing 100029, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2681-278X","authenticated-orcid":false,"given":"Di","family":"Yao","sequence":"additional","affiliation":[{"name":"School of Economics and Management, Beijing Institute of Petrochemical Technology, Beijing 102617, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101520","DOI":"10.1016\/j.retrec.2025.101520","article-title":"Horizontal port integrations under mixed ownership","volume":"109","author":"Xu","year":"2025","journal-title":"Res. Transp. Econ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1080\/03088839.2011.650721","article-title":"Why are maritime ports (still) urban, and why should policy-makers care?","volume":"39","author":"Hall","year":"2012","journal-title":"Marit. Policy Manag."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1080\/01441647.2011.597005","article-title":"Charting a New Paradigm of Container Hub Port Development Policy: The Asian Doctrine","volume":"31","author":"Lee","year":"2011","journal-title":"Transp. Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1016\/j.tranpol.2024.05.020","article-title":"Exploring the Evolution Trends of Port Integration Policy in China by a Text Mining Approach","volume":"153","author":"Chen","year":"2024","journal-title":"Transp. Policy"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Zhang, L., Zeng, Q., and Wang, L. (2024). How to Achieve Comprehensive Carbon Emission Reduction in Ports? A Systematic Review. J. Mar. Sci. Eng., 12.","DOI":"10.3390\/jmse12050715"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"100032","DOI":"10.1016\/j.martra.2021.100032","article-title":"Lessons to Be Learned from Top-50 Global Container Port Terminals Efficiencies: A Multi-Period DEA-Tobit Approach","volume":"2","author":"Nikolaou","year":"2021","journal-title":"Marit. Transp. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.marpolbul.2019.03.061","article-title":"Efficiency in the Environmental Management of Plastic Wastes at Brazilian Ports Based on Data Envelopment Analysis","volume":"142","author":"Gobbi","year":"2019","journal-title":"Mar. Pollut. Bull."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4351","DOI":"10.1038\/s41467-022-32070-0","article-title":"Ports\u2019 Criticality in International Trade and Global Supply-Chains","volume":"13","author":"Verschuur","year":"2022","journal-title":"Nat. Commun."},{"key":"ref_9","first-page":"46","article-title":"Economic Assessment of the Alternative Energy Sources Implementation for Port Enterprises","volume":"166","author":"Yarova","year":"2017","journal-title":"Econ. Ann. XXI"},{"key":"ref_10","first-page":"18","article-title":"Analysis of the Case of Port Co-Operation and Integration in Liaoning (China)","volume":"26","author":"Wu","year":"2018","journal-title":"Res. Transp. Bus. Manag."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"777","DOI":"10.1080\/03088839.2016.1163431","article-title":"Influence of Local Government on Port Investment: Implications of China\u2019s Decentralized Port Governance System","volume":"43","author":"Wu","year":"2016","journal-title":"Marit. Policy Manag."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/j.tranpol.2019.03.001","article-title":"Port Governance Revisited: How to Govern and for What Purpose?","volume":"77","author":"Zhang","year":"2019","journal-title":"Transp. Policy"},{"key":"ref_13","first-page":"100243","article-title":"Core and Comprehensive Ports: The New Challenge for the Development of the Spanish Port System","volume":"8","year":"2020","journal-title":"Transp. Res. Interdiscip. Perspect."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1057\/mel.2008.1","article-title":"Concession Agreements and Market Entry in the Container Terminal Industry","volume":"10","author":"Pallis","year":"2008","journal-title":"Marit. Econ. Logist."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1504\/WRITR.2010.034667","article-title":"Establishing Intermodal Terminals","volume":"3","author":"Bergqvist","year":"2010","journal-title":"World Rev. Intermodal Transp. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1551","DOI":"10.1016\/j.tra.2012.07.008","article-title":"Giving a direction to port regionalisation","volume":"46","author":"Monios","year":"2012","journal-title":"Transp. Res. Part A Policy Pract."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1080\/21622671.2021.2014353","article-title":"Friends with Benefits: The Emergence of the Amsterdam\u2013Rotterdam\u2013Antwerp (ARA) Polycentric Port Region","volume":"11","author":"Berghe","year":"2023","journal-title":"Territ. Politics Gov."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1007\/s11769-015-0752-3","article-title":"Port Integration in China: Temporal Pathways, Spatial Patterns and Dynamics","volume":"25","author":"Wang","year":"2015","journal-title":"Chin. Geogr. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1016\/S0966-6923(01)00020-5","article-title":"The Regionalization of Hutchison Port Holdings in Mainland China","volume":"9","author":"Airriess","year":"2001","journal-title":"J. Transp. Geogr."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1272","DOI":"10.1016\/j.jtrangeo.2011.06.007","article-title":"Dynamics of Liner Shipping Network and Port Connectivity in Supply Chain Systems: Analysis on East Asia","volume":"19","author":"Lam","year":"2011","journal-title":"J. Transp. Geogr."},{"key":"ref_21","first-page":"67","article-title":"Recent Development of Chinese Port Cooperation Strategies","volume":"26","author":"Huo","year":"2018","journal-title":"Res. Transp. Bus. Manag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1080\/03088830210132614","article-title":"Consolidation and Contestability in the European Container Handling Industry","volume":"29","author":"Notteboom","year":"2002","journal-title":"Marit. Policy Manag."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1016\/j.cstp.2017.03.009","article-title":"The Contribution of Transport Infrastructure to Economic Activity: The Case of Belgium","volume":"5","author":"Meersman","year":"2017","journal-title":"Case Stud. Transp. Policy"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"102660","DOI":"10.1016\/j.tre.2022.102660","article-title":"The Impacts of Port Governance Reform on Port Competition in China","volume":"160","author":"Cheng","year":"2022","journal-title":"Transp. Res. Part E Logist. Transp. Rev."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/j.tranpol.2014.08.003","article-title":"Port Infrastructure Investment and Regional Economic Growth in China: Panel Evidence in Port Regions and Provinces","volume":"36","author":"Song","year":"2014","journal-title":"Transp. Policy"},{"key":"ref_26","first-page":"131","article-title":"Study on the Coupling Relationship between Modern Port Logistics and Port-Vicinity Industry Agglomeration: A Case Study of Dalian Port","volume":"9","author":"Li","year":"2016","journal-title":"Int. J. u-e-Serv. Sci. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"103744","DOI":"10.1016\/j.trd.2023.103744","article-title":"Impact Analysis of Environmental Policies on Shipping Fleet Planning under Demand Uncertainty","volume":"120","author":"Chua","year":"2023","journal-title":"Transp. Res. Part D Transp. Environ."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Li, X.Z., Peng, Z.R., and Fu, Q. (2024). A Data-Driven Approach to Identify Major Air Pollutants in Shanghai Port Area and Their Contributing Factors. J. Mar. Sci. Eng., 12.","DOI":"10.3390\/jmse12020288"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"552","DOI":"10.1016\/j.ejor.2018.12.003","article-title":"Carbon-Efficient Deployment of Electric Rubber-Tyred Gantry Cranes in Container Terminals with Workload Uncertainty","volume":"275","author":"Yu","year":"2019","journal-title":"Eur. J. Oper. Res."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Liu, C., Liu, F., Luo, X., and Qiu, J. (2009). The Analysis of Environmental Problems in Seas around Ports of China Based on Green Ideal. Logist. Emerg. Front. Transp. Dev. China, 390\u2013395.","DOI":"10.1061\/40996(330)55"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"7546742","DOI":"10.1155\/2022\/7546742","article-title":"Analysis and Prediction of Influence Factors of Green Computing on Carbon Cycle Process in Smart City","volume":"2022","author":"Huang","year":"2022","journal-title":"Comput. Intell. Neurosci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.ajsl.2021.11.003","article-title":"Strategic Port Management by Consolidating Container Terminals","volume":"38","author":"Kim","year":"2022","journal-title":"Asian J. Shipp. Logist."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2018","DOI":"10.1016\/j.trpro.2020.08.261","article-title":"Greenhouse Gas Emissions Associated with Road Transport Projects: Current Status, Benchmarking, and Assessment Tools","volume":"48","author":"Albuquerque","year":"2020","journal-title":"Transp. Res. Procedia"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"103257","DOI":"10.1016\/j.trd.2022.103257","article-title":"Impacts of a Bunker Levy on Decarbonizing Shipping: A Tanker Case Study","volume":"106","author":"Lagouvardou","year":"2022","journal-title":"Transp. Res. Part D Transp. Environ."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"100427","DOI":"10.1016\/j.ijnaoe.2021.11.010","article-title":"Activity-Based Evaluation of Ship Pollutant Emissions Considering Ship Maneuver According to Transportation Plan","volume":"14","author":"You","year":"2022","journal-title":"Int. J. Nav. Archit. Ocean Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2194","DOI":"10.1016\/j.atmosenv.2010.03.018","article-title":"Ship Emissions and Their Externalities for Greece","volume":"44","author":"Tzannatos","year":"2010","journal-title":"Atmos. Environ."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"4650","DOI":"10.1029\/2003JD003751","article-title":"Updated Emissions from Ocean Shipping","volume":"108","author":"Corbett","year":"2003","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Ballester, V.C., Lo-Iacono-Ferreira, V.G., Artacho-Ram\u00edrez, M.\u00c1., and Capuz-Rizo, S.F. (2020). The Carbon Footprint of Valencia Port: A Case Study of the Port Authority of Valencia (Spain). Int. J. Environ. Res. Public Health, 17.","DOI":"10.3390\/ijerph17218157"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"148063","DOI":"10.1016\/j.scitotenv.2021.148063","article-title":"The Impact of Shipping CO2 Emissions from Marine Traffic in Western Singapore Straits During COVID-19","volume":"789","author":"Ju","year":"2021","journal-title":"Sci. Total Environ."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Xu, X., Liu, X., Feng, L., Yap, W.Y., and Feng, H. (2025). Emission Estimation and Spatiotemporal Distribution of Passenger Ships Using Multi-Source Data: A Case from Zhoushan (China). J. Mar. Sci. Eng., 13.","DOI":"10.3390\/jmse13010168"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"104159","DOI":"10.1016\/j.tre.2025.104159","article-title":"Port Carbon Emission Estimation: Principles, Practices, and Machine Learning Applications","volume":"199","author":"Zhang","year":"2025","journal-title":"Transp. Res. Part E Logist. Transp. Rev."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"128107","DOI":"10.1016\/j.physa.2022.128107","article-title":"K-GCN-LSTM: A k-hop Graph Convolutional Network and Long-Short-Term Memory for Ship Speed Prediction","volume":"606","author":"Zhao","year":"2022","journal-title":"Phys. A Stat. Mech. Its Appl."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"408","DOI":"10.1016\/j.trd.2017.03.022","article-title":"State-of-the-Art Technologies, Measures, and Potential for Reducing GHG Emissions from Shipping\u2013A Review","volume":"52","author":"Bouman","year":"2017","journal-title":"Transp. Res. Part D Transp. Environ."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"142209","DOI":"10.1016\/j.jclepro.2024.142209","article-title":"Decarbonising Maritime Ports: A Systematic Review of the Literature and Insights for New Research Opportunities","volume":"452","author":"Fadiga","year":"2024","journal-title":"J. Clean. Prod."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Liu, H., Ju, K., and Guo, M. (2025). Theory and Practice of China\u2019s Shipping Carbon Tax Under the \u201cDual Carbon\u201d Targets. Front. Mar. Sci., 12.","DOI":"10.3389\/fmars.2025.1647326"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"5208046","DOI":"10.1155\/2021\/5208046","article-title":"Will Port Integration Help Reduce Carbon Emissions and Improve Social Welfare?","volume":"2021","author":"Teng","year":"2021","journal-title":"Discret. Dyn. Nat. Soc."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.trd.2016.03.007","article-title":"Reducing Speed and Fuel Transfer of the Green Flag Incentive Program in Kaohsiung Port Taiwan","volume":"46","author":"Chang","year":"2016","journal-title":"Transp. Res. Part D Transp. Environ."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.tranpol.2024.10.036","article-title":"Is Port Integration a Panacea for Regions Green Development: An Empirical Study of China Port City","volume":"160","author":"Ma","year":"2025","journal-title":"Transp. Policy"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1016\/j.jtrangeo.2017.01.014","article-title":"Building a bridge between port and city: Improving the urban competitiveness of port cities","volume":"59","author":"Zhao","year":"2017","journal-title":"J. Transp. Geogr."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"139407","DOI":"10.1016\/j.scitotenv.2020.139407","article-title":"Calculating the Carbon Footprint in Ports by Using a Standardized Tool","volume":"734","author":"Azarkamand","year":"2020","journal-title":"Sci. Total Environ."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"125170","DOI":"10.1016\/j.envpol.2024.125170","article-title":"The Challenge of Benchmarking Carbon Emissions in Maritime Ports","volume":"363","author":"Freitas","year":"2024","journal-title":"Environ. Pollut."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"115451","DOI":"10.1016\/j.marpolbul.2023.115451","article-title":"Estimation Methods and Reduction Strategies of Port Carbon Emissions-What Literatures Say?","volume":"195","author":"Wang","year":"2023","journal-title":"Mar. Pollut. Bull."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Li, J., Ren, J., and Ma, X. (2023). Environmental Efficiency of Ports under the Dual Carbon Goals: Taking China\u2019s Bohai-Rim Ports as an Example. Front. Mar. Sci., 10.","DOI":"10.3389\/fmars.2023.1129659"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"29099","DOI":"10.1007\/s10668-023-03856-z","article-title":"Evaluation and Analysis of Green Efficiency of China\u2019s Coastal Ports under the \u201cDouble Carbon\u201d Goal: Two Improved DEA Models with CO2 Emissions","volume":"26","author":"Cui","year":"2024","journal-title":"Environ. Dev. Sustain."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Zhang, J.W., and Gu, G.F. (2025). An Evaluation of Port Environmental Efficiency Considering Heterogeneous Abatement Capacities: Integrating Weak Disposability into the Epsilon-Based Measure Model. J. Mar. Sci. Eng., 13.","DOI":"10.3390\/jmse13112064"},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Gu, G.F., Zhang, J.W., and Pan, X.F. (2025). A Meta-Frontier Approach to Evaluating the Environmental Efficiency of Coastal Ports: Implications for Port Sustainability. J. Mar. Sci. Eng., 13.","DOI":"10.3390\/jmse13071272"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"103574","DOI":"10.1016\/j.jtrangeo.2023.103574","article-title":"The Impact of Provincial Port Integration on Port Efficiency: Empirical Evidence from China\u2019s Coastal Provinces","volume":"108","author":"Zhou","year":"2023","journal-title":"J. Transp. Geogr."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"129048","DOI":"10.1016\/j.energy.2023.129048","article-title":"Does China\u2019s Low-carbon City Pilot Policy Improve Energy Efficiency","volume":"283","author":"Wang","year":"2023","journal-title":"Energy"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"31578","DOI":"10.1007\/s11356-021-17977-3","article-title":"Analysis on the Causes of the Change in the North-South Gap of Industrial Pollution Discharge in China","volume":"29","author":"Zhang","year":"2022","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"107485","DOI":"10.1016\/j.ocecoaman.2024.107485","article-title":"Port Governance and Sustainable Development: The Impact of Port Smartization on Port Carbon Emission Efficiency","volume":"259","author":"Zhang","year":"2024","journal-title":"Ocean Coast. Manag."},{"key":"ref_61","doi-asserted-by":"crossref","unstructured":"Wang, T., Xiao, G., and Li, Q. (2025). The Impact of the 21st-Century Maritime Silk Road on Sulfur Dioxide Emissions in Chinese Ports: Based on the Difference-in-difference Model. Front. Mar. Sci., 12.","DOI":"10.3389\/fmars.2025.1608803"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"128958","DOI":"10.1016\/j.jclepro.2021.128958","article-title":"Has the opening of high-speed rail reduced urban carbon emissions? Empirical analysis based on panel data of cities in China","volume":"321","author":"Sun","year":"2021","journal-title":"J. Clean. Prod."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1057\/s41599-026-06509-4","article-title":"ICT Investment and Carbon Emission Efficiency in Regional Port Groups: Evidence from Chinese Coastal Provinces","volume":"13","author":"Jin","year":"2026","journal-title":"Humanit. Soc. Sci. Commun."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"113180","DOI":"10.1016\/j.enpol.2022.113180","article-title":"Research on Energy Conservation and Carbon Emission Reduction Effects and Mechanism: Quasi-experimental Evidence from China","volume":"169","author":"Wen","year":"2022","journal-title":"Energy Policy"},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"106797","DOI":"10.1016\/j.frl.2025.106797","article-title":"Fostering Green Technological Innovation through Carbon Emission Trading Policies","volume":"74","author":"Hu","year":"2025","journal-title":"Financ. Res. Lett."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1080\/09638190902792464","article-title":"International R&D spillovers in emerging markets: The impact of trade and foreign direct investment","volume":"19","author":"Krammer","year":"2010","journal-title":"J. Int. Trade Econ. Dev."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1257\/app.4.4.1","article-title":"Soap Operas and Fertility: Evidence from Brazil","volume":"4","author":"Ferrara","year":"2012","journal-title":"Am. Econ. J. Appl. Econ."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1111\/j.1467-6419.2007.00527.x","article-title":"Some Practical Guidance for the Implementation of Propensity Score Matching","volume":"22","author":"Caliendo","year":"2008","journal-title":"J. Econ. Surv."}],"container-title":["Systems"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-8954\/14\/6\/662\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T06:28:43Z","timestamp":1781159323000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-8954\/14\/6\/662"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,9]]},"references-count":68,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["systems14060662"],"URL":"https:\/\/doi.org\/10.3390\/systems14060662","relation":{},"ISSN":["2079-8954"],"issn-type":[{"value":"2079-8954","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,9]]}}}