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1.
Environ Sci Pollut Res Int ; 31(23): 33685-33707, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38691282

RESUMO

Carbon dioxide (CO2) emissions result from human activities like burning fossil fuels. CO2 is a greenhouse gas, contributing to global warming and climate change. Efforts to reduce CO2 emissions include transitioning to renewable energy. Monitoring and reducing CO2 emissions are crucial for mitigating climate change. Strategies include energy efficiency and renewable energy adoption. In the past few decades, several nations have experienced air pollution and environmental difficulties because of carbon dioxide (CO2) emissions. One of the most crucial methods for regulating and maximizing CO2 emission reductions is precise forecasting. Four machine learning algorithms with high forecasting precision and low data requirements were developed in this study to estimate CO2 emissions in the United States (US). Data from a dataset covering the years 1973/01 to 2022/07 that included information on different energy sources that had an impact on CO2 emissions were examined. Then, four algorithms performed the CO2 emissions forecast from the layer recurrent neural network with 10 nodes (L-RNN), a feed-forward neural network with 10 nodes (FFNN), a convolutional neural network with two layers with 10 and 5 filters (CNN1), and convolutional neural network with two layers and with 50 and 25 filters (CNN2) models. Each algorithm's forecast accuracy was assessed using eight indicators. The three preprocessing techniques used are (1) without any processing techniques, (2) processed using max-min normalization technique, and (3) processed using max-min normalization technique and decomposed by variation mode decomposition (VMD) technique with 7 intrinsic mode functions and 1000 iterations. The latter with L-RNN algorithm gave a high accuracy between the forecasting and actual values. The results of CO2 emissions from 2011/05 to 2022/07 have been forecasted, and the L-RNN algorithm had the highest forecast accuracy. The L-RNN model has the lowest value of 1.187028078, 135.5668592, and 11.64331822 for MAPE, MSE, and RMSE, respectively. The L-RNN model provides precise and timely forecasts that can help formulate plans to reduce carbon emissions and contribute to a more sustainable future. Moreover, the results of this investigation can improve our comprehension of the dynamics of carbon dioxide emissions, resulting in better-informed environmental policies and initiatives targeted at lowering carbon emissions.


Assuntos
Algoritmos , Dióxido de Carbono , Aprendizado de Máquina , Dióxido de Carbono/análise , Estados Unidos , Poluição do Ar , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Mudança Climática , Previsões
2.
PLoS One ; 16(3): e0246502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33662004

RESUMO

Post-colonial land tenure reforms in emerging countries have partly aimed at poverty reduction through equitable land access. However, the poverty rate keeps rising in rural and peri-urban settings in Sub-Saharan Africa dominated by agricultural activities. This article reviews land tenure reforms in Mali, from the year 2000 to 2017 regarding poverty alleviation and evaluates their impacts on indigenous smallholder farmers, using multiple linear and logistic regression models and local experts' elicitations. The results indicate that the advent of land titles as the only definitive evidence of land ownership, following the reforms, has generally weakened customary land management. Smallholder farmers face several barriers to obtaining land titles, limiting equity in land access and security. This has paved way for land markets marred by irregularities and resulted in colossal loss of agricultural lands, which are the main source of rural livelihood. Thus, the reforms have not yielded the intended poverty reduction outcomes. The study recommends that land transfers must be authorised by a single institution, represented at the various administrative levels, which issues an authentic and incorruptible document using appropriate technology. Moreover, since pro-poor provisions in the reforms usually lack implementing decrees in Mali, political will is key to achieving equitable land access and security.


Assuntos
Agricultura/legislação & jurisprudência , Pobreza/prevenção & controle , Países em Desenvolvimento , Pesquisa Empírica , Feminino , Humanos , Povos Indígenas , Masculino , Mali/etnologia , Pobreza/etnologia , Análise de Regressão , População Rural , Fatores Socioeconômicos , População Suburbana
3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-476170

RESUMO

BACKGROUND:There are many methods that can repair Pilon fracture, but the effects are not ideal. With the development of science and technology, fundamental change of fracture fixation principle and innovation of technology and idea has brought new opportunities for Pilon fracture repair. Biological immobilization technology can further reduce the further damage to blood supply of bone outer membrane on the fracture end, do not disturb biomechanical environment of fracture healing, and is the new trend of present research and development. OBJECTIVE:To investigate the effect of locking compression plate fixation for repair of Pilon fracture using biological fixation technique. METHODS:Clinical data of 76 patients with Pilon fracture treated using locking compression plate fixation in the Nanhai District Economic Development Zone Guanyao Branch of the People’s Hospital from June 2008 to December 2013 were retrospectively analyzed. There were 49 males and 27 females, at the age of 39.5 years on average (range from 19 to 60 years). According to Ruedi-Algower classification, there were 54 cases of type II and 22 cases of type III. In accordance with biological fixation technique, locking compression plate fixation was applied to treat Pilon fracture. Folowing treatment, they were regularly folowed up. Reduction quality was assessed by Burwel-Charnley radiological criteria. X-ray films were reviewed to observe fracture healing. During final folow-up, ankle function was evaluated according to Baird-Jackson score. RESULTS AND CONCLUSION:A total of 76 patients were folowed up for 6 to 24 months. Reduction quality assessed by Burwel-Charnley radiological criteria was as folows: anatomic reduction of 68 cases, reduction of 8 cases, 71 cases of one-stage wound healing, and 5 cases of wound healing after dressing change, with the rate of one-stage healing of 93%. Fractures of al patients were healed. The healing time was 4 to 8.5 months, averagely 6.25 months. During final folow-up, ankle function assessed by Baird-Jackson score was as folows: there were 69 excelent cases, 5 good cases and 2 average cases. These results indicate that locking compression plate fixation for Pilon fracture obtained good stability, could effectively avoid the damage of fracture end blood supply, shorten the healing time; it was simple to operate, had smal injury to soft tissue, and was an effective fixation method to repair Pilon fracture.

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