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Forecasting stock market returns using deep learning and time series techniques: a comparative and empirical study using technical indicators

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Multimedia Tools and Applications 2024年 1-21页

作者： Fahd, Kalloubi Badr, Hirchoua Eddine, Labiad Salah Mouad, Aterhi LTI Laboratory National School of Applied Sciences El Jadida Morocco Casablanca Morocco Modeling Simulation and Data Analysis Mohammed VI Polytechnic University Ben Guerir Morocco

Deep learning models enable learning strategic and accurate behaviors. Nevertheless, training accurate models in dynamic environments, such as stock markets, has been a long-standing challenge. They suffer from partial observability, long-term dependencies, and require merging different handcrafted features. Moreover, selecting the model architecture and fine-tuning different parameters is very challenging. In this paper, we conduct a comparative and empirical study of different possible scenarios. We demonstrate and provide a solid recommendation for possible network architectures. Precisely, we compare different recurrent neural network models alongside time series techniques and report their influence on out-of-sample stock returns. Furthermore, we run an empirical study to determine the best features and hyperparameters using several feature importance techniques. Strong technical indicators have fueled the input prices to push the input representation forward. Extensive experiments have been presented to evaluate the performance of different models, and the results are critically analyzed and empirically verified. The results demonstrate that bidirectional recurrent neural networks and the autoregressive integrated moving average with explanatory variable model provide better performances in predicting the following day’s closing price and provide better references and insights for future investments. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.

关键词： Prediction models

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Multi-Cell Discrete-Time SIRI Epidemic Model with Travel Restrictions and Vaccination Controls

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International Journal of Applied and Computational Mathematics 2024年第6期10卷 1-20页

作者： Zouhri, Samira El Baroudi, Mohcine Laarabi, Hassan Laboratory of Analysis Modeling and Simulation (LAMS) Department of Mathematics and Computer Science Faculty of Sciences Ben M’sik Hassan II University of Casablanca BP 7955 Sidi Othman Casablanca Morocco

In this paper, we propose a multi-cell discrete-time SIRI epidemic model that describes the spatial-temporal spread of an infectious disease in a geographical domain represented as a grid of cells (regions) divided into p² cells. We assume that people can move between these cells due to their connectivity. To investigate the efficacy of travel restrictions and vaccination in preventing epidemic spread, we include two control variables in our model. We aim to reduce the number of infected individuals in each cell designated as infectious by the health authority, while also minimizing the expenses associated with implementing the travel ban and vaccination efforts. We develop an optimal control approach using the definition of a supplementary function that identifies the automatic activation of travel restrictions and vaccination in every cell according to health authority decisions. We present numerical results testing the spread of epidemics without any intervention, applying travel restrictions only, implementing vaccination only, and combining the two strategies. © The Author(s), under exclusive licence to Springer Nature India Private Limited 2024.

关键词： Discrete SIRI model Multi-cell Optimal control Travel restrictions Vaccination

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Optimal Control in a Mathematical Model for the Occurrence of Electronic Cheating in Certification Exams;Baccalaureate Exams in Morocco as an Example

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Operations Research Forum 2024年第4期5卷 104页

作者： El Mansouri, Abdelbar Khajji, Bouchaib Labzai, Abderrahim Belam, Mohamed Laboratory LMACS Department of Mathematics and Computer Science Khouribga Polydisciplinary Faculty Sultan Moulay Slimane University Beni Mellal Morocco Laboratory of Analysis Modeling and Simulation Department of Mathematics and Computer Science Faculty of Sciences Ben M’Sik Hassan II University of Casablanca Casablanca Morocco

Researchers across a range of fields have raised concerns about the serious rise in the phenomenon of school cheating among pupils and students, which has a negative impact on the quality of education and training. This is because cheating has gone from being an unacceptable act to being a” legitimate right” for a large group of students. Here, we offer a model using mathematics to attempt to understand how this scandalous occurrence spreads among Moroccan students, particularly those in their second year of baccalaureate, and we also examine the effectiveness of some of the suggested solutions. Our method leverages Pontryagin’s maximum principle to identify the best control strategies, and we then apply iterative methods to solve the system that results. Lastly, we validate our theoretical analysis with numerical simulations conducted using MATLAB. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.

关键词： 34H05 34K28 34K35 49J25 93C15 Academic performance Cheating practices Objective functional Pontryagin’s maximum principle School cheating

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Impacts of meteorology and emission variations on the heavy air pollution episode in North China around the 2020 Spring Festival

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Science China Earth Sciences 2021年第2期64卷 329-339页

作者： Wenbo XUE Xurong SHI Gang YAN Jinnan WANG Yanling XU Qian TANG Yanli WANG Yixuan ZHENG Yu LEI Center of Air Modeling and Systems Analysis Chinese Academy for Environmental PlanningBeijing 100012China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy for Environmental PlanningBeijing 100012China

Based on the Weather Research and Forecasting model and the Models-3 community multi-scale air quality model(WRF-CMAQ),this study analyzes the impacts of meteorological conditions and changes in air pollutant emissions on the heavy air pollution episode occurred over North China around the 2020 Spring Festival(January to Februray 2020).Regional reductions in air pollutant emissions required to eliminate the PM2.5 heavy pollution episode are also *** results found that meteorological conditions for the Beijing-Tianjin-Hebei and surrounding"2+26"cities are the worst during the heavy pollution episode around the 2020 Spring Festival as compared with two other typical heavy pollution episodes that occurred after ***,because of the substantial reductions in air pollutant emissions in the"2+26"cities in recent years,and the32%extra reduction in emissions during January to February 2020 compared with the baseline emission levels of the autumn and winter of 2019 to 2020,the maximum PM2.5 level during this heavy pollution episode around the 2020 Spring Festival was much lower than that in the other two typical ***,these emission reductions are still not enough to eliminate regional heavy pollution *** with the actual emission levels during January to February 2020,a 20%extra reduction in air pollutant emissions in the"2+26"cities(or a 45%extra reduction compared with baseline emission levels of the autumn and winter of 2019 to 2020)could help to generally eliminate regionwide severe pollution episodes,and avoid heavy pollution episodes that last three or more consecutive days in Beijing;a 40%extra reduction in emissions(or a 60%extra reduction compared with baseline emission levels of the autumn and winter of 2019 to 2020)could help to generally eliminate regionwide and continuous heavy pollution *** analysis finds that during the clean period after the heavy pollution episode around the 2020 Spring Festival,the regionwide

关键词： "2+26"cities 2020 Spring Festival Heavy air pollution episode WRF-CMAQ model

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Mathematical modeling of the spread of the COVID'19 with optimal control strategies 17

Mathematical modeling of the spread of the COVID'19 with opt...

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17th International Conference on Future Networks and Communications / 19th International Conference on Mobile Systems and Pervasive Computing / 12th International Conference on Sustainable Energy Information Technology, FNC/MobiSPC/SEIT 2022

作者： Riouali, Maryam Lahmidi, Fouad Elbarrai, Imane Namir, Abdelwahe Laboratory of Analysis Modeling and Simulation Hassan II University Faculty of Sciences Ben M'sik B.P 7955 Casablanca Morocco Laboratory of Information Technology and Modeling Hassan II University Faculty of Sciences Ben M'sik B.P 7955 Casablanca Morocco

In this work, we formulated an SEQIRS mathematical model with four control variables, which describes the spread of the coronavirus in a community. An optimal control problem was well introduced in order to verify the existence of optimal controls that minimize susceptible, exposed, and infected individuals. Also, we use Pontryagin's Maximum Principle to characterize the optimal control strategies to minimize the spread dynamics of the COVID'19. © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://***/licenses/by-nc-nd/4.0) Peer-review under responsibility of the Conference Program Chairs.

关键词： COVID-19

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Trends and drivers of anthropogenic NOx emissions in China since 2020

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Environmental Science and Ecotechnology 2024年第5期21卷 287-293页

作者： Hui Li Bo Zheng Yu Lei Didier Hauglustaine Cuihong Chen Xin Lin Yi Zhang Qiang Zhang Kebin He Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration Institute of Environment and EcologyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation and Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental PlanningBeijing 100041China Laboratoire des Sciences du Climat et de l’Environnement LSCE/IPSLCEA-CNRS-UVSQUniversite Paris-SaclayGif-sur-YvetteFrance Center for Satellite Application on Ecology and Environment Ministry of Ecology and Environment of ChinaBeijing 100094China Institute of Future Human Habitats Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

Nitrogen oxides(NOx),significant contributors to air pollution and climate change,form aerosols and ozone in the ***,timely,and transparent information on NOx emissions is essential for decision-making to mitigate both haze and ozone ***,a comprehensive understanding of the trends and drivers behind anthropogenic NOx emissions from Chinadthe world's largest emitterdhas been lacking since 2020 due to delays in emissions *** we show a consistent decline in China's NOx emissions from 2020 to 2022,despite increased fossil fuel consumption,utilizing satellite observations as constraints for NOx emission estimates through atmospheric *** reduction is corroborated by data from two independent spaceborne instruments:the TROPOspheric Monitoring Instrument(TROPOMI)and the Ozone Monitoring Instrument(OMI).Notably,a reduction in transport emissions,largely due to the COVID-19 lockdowns,slightly decreased China's NOx emissions in *** subsequent years,2021 and 2022,reductions in NOx emissions were driven by the industry and transport sectors,influenced by stringent air pollution *** satellite-based inversion system developed in this study represents a significant advancement in the real-time monitoring of regional air pollution emissions from space.

关键词： China's NOx emissions Pollution control Socio-economic drivers Atmospheric inversion

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On the Null Controllability of Switched Positive and Periodic Positive Systems

SSRN

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SSRN 2022年

作者： Sitli, Ilyas Lahmidi, Fouad Laboratory of Analysis Modeling and Simulation Faculty of Sciences Ben M’sik Hassan II University Casablanca Morocco

In this paper, we study the null controllability of switched positive systems and periodic positive systems. We solve this problem by a technique based on the graph theory. © 2022, The Authors. All rights reserved.

关键词： Graph theory

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FIXED POINT THEOREMS FOR GENERALIZED θ − φ−CONTRACTION MAPPINGS IN RECTANGULAR QUASI B-METRIC SPACES

arXiv

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arXiv 2024年

作者： Rossafi, Mohamed Kari, Abdelkarim Higher School of Education and Training University of Ibn Tofail Kenitra Morocco Laboratory of Analysis Modeling and Simulation Faculty of Sciences Ben M’Sik Hassan II University CasablancaB.P. 7955 Morocco

A generalized version of both rectangular metric spaces and rectangular quasimetric spaces is known as rectangular quasi b-metric spaces (RQB-MS). In the current work, we define generalized (θ, φ)-contraction mappings and study fixed point (FP) results for the maps introduced in the setting of rectangular quasi b-metric spaces. Our results generalize many existing results. We also provide examples in support of our main *** Codes Primary 47H10, Secondary 54H25 © 2024, CC BY.

关键词： Topology

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Expanding carbon neutrality strategies:Incorporating out-ofboundary emissions in city-level frameworks

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Environmental Science and Ecotechnology 2024年第4期20卷 145-153页

作者： Zhe Zhang Mingyu Li Li Zhang Yunfeng Zhou Shuying Zhu Chen Lv Yixuan Zheng Bofeng Cai Jinnan Wang Center for Carbon Neutrality Chinese Academy of Environmental PlanningBeijing100043China School of Environment Tsinghua UniversityBeijing100084China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing100084China R&D and International Cooperation Office Chinese Academy of Environmental PlanningBeijing100043China School of Economics and Management Beijing University of Chemical TechnologyBeijing100029China Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental PlanningBeijing100043China

Cities are increasingly vital in global carbon mitigation efforts,yet few have specifically tailored carbon neutrality ***,out-of-boundary indirect greenhouse gas(GHG)emissions,aside from those related to electricity and heat imports,are often overlooked in existing pathways,despite their significance in comprehensive carbon mitigation *** this gap,here we introduce an integrated analysis framework focusing on both production and consumption-related GHG *** to Wuyishan,a service-oriented city in Southern China,this framework provides a holistic view of a city's carbon neutrality pathway,from a full-scope GHG emission *** findings reveal the equal importance of carbon reduction within and outside the city's boundaries,with out-of-boundary emissions accounting for 42%of Wuyishan's present total GHG *** insight highlights the necessity of including these external factors in GHG accounting and mitigation strategy *** framework serves as a practical tool for cities,particularly in developing countries,to craft effective carbon neutrality roadmaps that encompass the full spectrum of GHG emissions.

关键词： Greenhouse gas emissions Full-scope emission accounting Carbon neutrality pathway City-level

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New WHO global air quality guidelines help prevent premature deaths in China

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National Science Review 2022年第4期9卷 10-12页

作者： Tao Xue Guannan Geng Xia Meng Qingyang Xiao Yixuan Zheng Jicheng Gong Jun Liu Wei Wan Qiang Zhang Haidong Kan Shiqiu Zhang Tong Zhu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics School of Public HealthPeking University State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University School of Public Health Key Laboratory of Public Health Safety of the Ministry of Educationand Key Laboratory of Health Technology Assessment of the Ministry of HealthFudan University Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental Planning College of Environmental Sciences and Engineering Peking University School of Energy and Environmental Engineering University of Science and Technology Beijing Clean Air Asia Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua University

The air quality guidelines （AQGs） issued by the World Health Organization （WHO） in 2005 are key references for the National Ambient Air Quality Standards （NAAQSs） in *** 22September 2021,the WHO issued new AQGs （NAQGs）[1],which propose more stringent targets to control exposure to multiple air pollutants,including fine particulate matter (PM2.5) and ozone （O3）,to which,in 2019,451 million premature deaths,globally,were attributable [2].

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