Energy Exploration & Exploitation最新文献

{"title":"Study on cracking mechanism and key parameters of roof in gob-side entry retaining by pre-split blasting roof in deep mine","authors":"Xiao Liu, Xueqiu He, Yuntao Liang, Xinzhu Hua, Chen Li","doi":"10.1177/01445987241269551","DOIUrl":"https://doi.org/10.1177/01445987241269551","url":null,"abstract":"Based on 7135 working face of Qidong Coal Mine, the cracking mechanism of pre-splitting of gob-side entry retaining by roof cutting and the key parameters of pre-splitting blasting are studied by means of theoretical analysis, numerical simulation, and on-site measurement. Under the same blasting conditions, the energy of shaped-charge blasting in the direction of shaped charge is much larger than that of non-shaped-charge blasting, and the cracks generated along the direction of shaped charge are longer than that of non-shaped-charge blasting. The key parameters of pre-splitting cracks are the hole spacing and charge length. The crack propagation law of two holes blasting at the same time with different blasting methods, different linear charge density, and different hole spacing is studied. It is obtained that the cracking effect of shaped-charge blasting with the same hole spacing is better than that of non-shaped-charge blasting, showing that it can form part-through cracks; Increasing the linear charge density can increase the crack distance, but also destroy the integrity of the retained rock mass. The key parameters of advanced pre-splitting blasting in engineering practice are put forward. Generally, the maximum hole spacing and the minimum charge length that can produce part-through cracks are selected. When the hole spacing is 600 mm and the charge length is 4 m, the crack propagation of roof and the stress change of anchor cable after blasting are measured, and the crack formation rate reaches 86% to 90% within the blasting depth of blasting hole, and the anchor cable is in a good stress state, which can effectively control the roof. The research results provide a theoretical basis for the parameter design of pre-splitting blasting cracking of gob-side entry retaining by roof cutting.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"37 26","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141924245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population, carbon dioxide emissions and renewable energy consumption nexus: New insights from Vietnam","authors":"Anh Nguyen Thi Mai, Vu Ngoc Xuan, Huong Le Mai, Hoa Pham Xuan, Thu Nguyen Thi Phuong","doi":"10.1177/01445987241252453","DOIUrl":"https://doi.org/10.1177/01445987241252453","url":null,"abstract":"This academic paper investigates the intricate relationships among population dynamics, carbon dioxide (CO2) emissions and renewable energy consumption in Vietnam. The study used the Autoregressive Distributed Lag approach and fixed panel data method to examine the nexus between population, CO2 emissions and renewable energy consumption in Vietnam. The data is collected at the World Bank from 2000 to 2023. As the nation undergoes rapid economic development and urbanization, understanding the nexus between population growth, environmental impact and the transition to renewable energy sources becomes crucial. The study employs a multidimensional analytical approach that integrates demographic trends, environmental science and energy economics to unveil novel evidence into the complex interplay of these factors. The significant findings indicate a positive trajectory in renewable energy consumption, with notable contributions from solar, wind and hydropower sources. Concurrently, population growth, particularly in urban centres, correlates with increased CO2 emissions, emphasizing the role of demographic shifts in environmental impact. Policy implications derived from these results underscore the need for integrated strategies. Targeted policies promoting renewable energy in urban centres, incentivizing cleaner industrial practices and fostering community engagement emerge as crucial avenues for sustainable development. In essence, this study contributes valuable insights into the dynamic relationships among population dynamics, CO2 emissions and renewable energy consumption in Vietnam, offering a foundation for evidence-based policymaking and guiding future research endeavours in sustainable development.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"15 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141106788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of digitalization and green technology innovation on energy efficiency in the European Union","authors":"Hind Alofaysan, Magdalena Radulescu, Izabela Dembińska, K. Si Mohammed","doi":"10.1177/01445987241253621","DOIUrl":"https://doi.org/10.1177/01445987241253621","url":null,"abstract":"This paper aims to scrutinize the effect of Green technology innovation, digitalization, renewable energy use, environmental taxes, GDP, energy prices, and population on energy efficiency in a panel comprising 22 member nations of the European Union. Using the generalized least squares and the panel-corrected standard error, we found (1) the positive effect of digitalization, green patterns, and renewable sources on energy efficiency. (2) The environmental tax has a limited and insignificant effect. (3) On the contrary, the population, GDP, and energy prices negatively affect energy efficiency. Based on the findings, relevant economic and environmental policies have been proposed for energy, technology stakeholders, and policy decision-makers, including substantial investment in digital infrastructure to facilitate the adoption of smart grids, Internet of Things devices, and advanced data analytics for energy management","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"9 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141110046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A transfer learning-based hybrid model with LightGBM for smart grid short-term energy load prediction","authors":"Sarita Simaiya, Mamta Dahiya, Shilpi Tomar, Neetu Faujdar, Yogesh Kumar Sharma, Nasratullah Nuristani","doi":"10.1177/01445987241256472","DOIUrl":"https://doi.org/10.1177/01445987241256472","url":null,"abstract":"Efficient energy management is crucial given 2024's 4.1% worldwide electricity demand increase. This urgency emphasizes the necessity for various, sustainable energy sources in distribution grids. Short-term load prediction approaches using probabilistic power generation and energy storage are crucial for energy usage prediction. Urban energy planners use simulation, probability optimization and modelling to create sustainable energy systems. This study offers a novel hybrid model for smart grids: short-term energy load prediction using transfer learning (TL) and optimized lightGBM (OLGBM). Our two-phase solution tackles Short-term Load Forecasting complexities. First, aberrant supplements and quick deviation selection eliminate missing values and identify key features during data pre-processing. Second, TL-OLGBM learns dynamic time scales and complex data patterns with Bayesian optimization of hyperparameters to improve forecasting accuracy. Additionally, our architecture easily combines the newest Smart and Green Technology, enabling energy system innovation. Comparative performance research shows that our technique outperforms similar models in mean absolute percentage error, accuracy and root mean square error. This hybrid model is a reliable short-term energy load forecast solution that fits the dynamic terrain of smart and green technology integration in modern energy systems.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141112911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal assessment of cylindrical parabolic integrated collector storage using input-output and dynamic system testing procedures: Experimental and numerical study","authors":"Anis Messaouda, Mohamed Hamdi, Majdi Hazami, AmenAllah Guizani","doi":"10.1177/01445987241253118","DOIUrl":"https://doi.org/10.1177/01445987241253118","url":null,"abstract":"The main limitation of Integrated Collector Storage systems lies in their low efficiencies and high loss coefficients. In this paper, experimental and numerical setups are conducted to assess the thermal performances of low cost Cylindrical Parabolic Integrated Collector storage (CP-ICS). The conceived system has two aluminum plates in parabolic form serving as reflectors, each with a surface area of 2 m2. The storage tank has a volume of 160 L covered with a layer of black paint with single and double transparent insulations. Results of the experimental tests using Input-Output method showed that the daily thermal efficiency ηd of the developed systems is equal to 48.21% and 49.46% for single and double insulation cover configurations, respectively. The total store heat capacity Cs, the useful collector surface Ac* and the storage tank heat losses coefficient Us of the system found using Dynamic System Testing procedure are equal to 0.56 MJ/K, 0.74 m2 and 1.59 W/K, respectively. Even if the energy efficiency of the system is slightly lower than that recorded in conventional systems, numerical results of long-term study using TRNSYS software showed that the system provides a reasonable solar fraction for the needs of a family in Tunisian climate. A comparative assessment of the developed solar collector performances in different representative climates showed that the use of the CP-ICS system presents a promising solution for countries with annual ambient temperatures fluctuating from 13°C to 33°C, such as Araxos with a solar coverage of 30.65% for a daily supply volume of 160 L. More importantly, in Faya-Largeau location, presenting Chadian climate data, the solar fraction is found to be the highest and reached an average of 67.25%.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"41 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140975408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prioritizing sustainable renewable energy systems in Tunisia: An integrated approach using hybrid multi-criteria decision analysis","authors":"Sassi Rekik, Souheil El Alimi","doi":"10.1177/01445987231226337","DOIUrl":"https://doi.org/10.1177/01445987231226337","url":null,"abstract":"In recent years, renewable energy technologies (RETs) have become increasingly popular worldwide to achieve energy sufficiency, reduce reliance on conventional fuels, and mitigate their devastating environmental impact. Nonetheless, more appears to have stayed the same in emerging economies, such as Tunisia, as various barriers hampered the implementation of these technologies. Hence, the prime objective of this article is to conduct a thoughtful assessment of four prominent renewable energy options for electricity generation and explore the most potential barriers hindering their development in Tunisia. To do so, a two-stage approach was applied. First, CRiteria Importance Through Inter-Criteria Correlation (CRITIC) and Evaluation based on Distance from Average Solution (EDAS) were used to evaluate the considered alternatives, namely solar PV, concentrated solar power (CSP), onshore wind, and biomass. Then, an integrated step-wise assessment ratio analysis and decision-making trial and evaluation laboratory approach (SWARA-DEMATEL) was developed to identify the most relevant barriers. The related criteria and barriers were determined based on an exhaustive literature review and experts’ feedback. The obtained results indicated that solar PV and wind were the most promising renewable technologies, while biomass was the worst option. To validate the outcome and demonstrate the effect of changing input data on the final results, a sensitivity analysis has been carried out. As for the key obstacles, political instability, high upfront costs, and market access mechanisms were the most influential barriers. Hence, prioritizing different RETs and analyzing the inherent barriers to their utilization would offer insightful guidance to policymakers, enabling them to establish efficient strategies for overcoming these obstacles, and accelerating the deployment of these technologies in the country.","PeriodicalId":444405,"journal":{"name":"Energy Exploration & Exploitation","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139603062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of functional groups on the microporous development and CO2-CH4 adsorption: A molecular simulation investigation","authors":"He Liu, Enyuan Wang","doi":"10.1177/01445987231218291","DOIUrl":"https://doi.org/10.1177/01445987231218291","url":null,"abstract":"In this study, the influence of different functional groups (carbonyl, ether, carboxyl, and hydroxyl) on microporous development and competitive adsorption for CO2-CH4 was investigated using Connolly potential theory, molecular mechanics, molecular dynamics, and grand canonical Monte Carlo based on the macromolecular representation of coal vitrinite (CV). Results indicated that microporous diameter induced from the carboxyl (COOH) and hydroxyl (OH) was more sensitive to increasing temperature than carbonyl (CO) and ether (C2O). The COOH and OH could induce more micropores than the other functional groups. The adsorption capacities of OH-CV and COOH-CV were significantly higher than C2O-CV, CO-CV, and C-CV (coal vitrinite purified by carbon atoms) and they all decrease with the decreasing temperature. Both the calculation results of Locate- and Isotherm task suggested that OH and COOH have a significantly higher adsorption amount than other coal macromolecules and the others have a close adsorption amount. The adsorption selectivities of CO2 over CH4 ( SA/B) for all the functional groups were higher than 1 here, indicating the adsorption preference of CO2 over CH4. For the pressure dependence, the SA/B first decreases significantly for the pressure of < 4 MPa and then slightly for the pressures of >4 MPa with the increasing pressure, indicating that high pressure was not conductive to the replacement of CH4 by CO2. For almost all the pressures here, the SA/B follows the order of COOH-CV > OH-CV≈C2O-CV≈Ori-CV≈CO-CV≈C-CV, indicating the highest adsorption preference of CO2 over CH4 for COOH, and OH-CV.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"57 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139603020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation and solution of a proppant migration and sedimentation model for hydraulically fractured inhomogeneously wide fractures","authors":"Xiong Peiqi, Sun Lin, Feipeng Wu, Song Aili, Jiyong Zhou, Xuguang Li, Haozhe Li","doi":"10.1177/01445987231222978","DOIUrl":"https://doi.org/10.1177/01445987231222978","url":null,"abstract":"The distribution of proppant during hydraulic fracturing may directly contribute to the flow conductivity of the proppant fracture, so research on the migration and sedimentation of proppant in the fracture and the final distribution pattern is of great relevance. The mass conservation equations of proppant solids and fracturing fluid were adopted to describe the distribution of proppant migration and sedimentation in the fracture, improving the additional gravity coefficient by utilizing the density difference between proppant and fracturing fluid and the concentration of proppant, together with the proppant sedimentation velocity at different Reynolds numbers in this study. The flow coefficients were obtained by discretizing the system of equations through the finite volume method combined with the harmonic mean method and the upstream weight method. The concentration additional pressure gradient term was computed by using the Superbee format innovatively to improve the solution convergence of the model. Numerical simulations with identical parameters were compared with indoor test results, which fully verified the correctness of the model and the accuracy of the discrete solution based on the finite volume method. The effects of flow rate of fracturing fluid, ratio of injected sand, viscosity of fracturing fluid, grain size of proppant and density of proppant on proppant migration and sedimentation based on three elliptical fracture morphologies: even-wide, top-wide and bottom-narrow as well as top-narrow and bottom-wide were investigated and analyzed through comparing the rate of proppant front movement, the level of sweeping range and the degree of inhomogeneity in the range under different conditions. Findings of this study suggest that: (1) top-wide and bottom-narrow fractures are more preferable for homogenous sanding in the early stage of proppant injection, and top-narrow and bottom-wide fractures are best for sanding in the later stage; (2) the viscosity of fracturing fluid is the most influential factor on proppant migration and sedimentation, which increases in the range of 100 mPa.s to enhance the sweeping range and homogeneity of proppant sanding and therefore achieve a better fracturing effect.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"31 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability analysis and control countermeasures of surrounding rock of gob-side entry formed by roof-cutting in inclined coal seams","authors":"Enze Zhen, Shizhuo Dong, Xiaowei Xu, Yajun Wang, Mengxiang Wang","doi":"10.1177/01445987241227574","DOIUrl":"https://doi.org/10.1177/01445987241227574","url":null,"abstract":"The stability of the surrounding rock in the inclined coal seam stope is crucial for the safety of the gob-side entry. In this article, we systematically analyze the surrounding rock stability of the gob-side entry formed by roof-cutting (GEFR) in an inclined coal seam. We identify three forms of roof structure evolution in the formation process of GEFR and analyze the two main modules affecting the deformation of the surrounding rock structure. We determine the critical elements of surrounding rock deformation in different stages of the GEFR retaining process. Further, we propose a classification of the deformation of the surrounding rock structure of GEFR into stress and structural types during stabilization. We analyze the length of the gangue side's bearing area and calculate the lateral gangue's impact energy. We establish three instability modes of the roof based on the fractured state of the roof structure of the GEFR and provide a mechanical criterion of instability. Finally, based on the results of our theoretical analysis, we propose a control principle for the surrounding rock deformation of GEFR and establish countermeasures for controlling the roof-cutting angle and an asymmetric coupling support system. A field case study was conducted under conditions involving an inclined thick coal seam to investigate the surrounding rock deformation and overburden stress evolution using field monitoring data. The field test results confirm that the control measures of the control roof-cutting angle and the asymmetric coupling support system positively impact the stability of the surrounding rock of the roof-cutting entry in an inclined coal seam.","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"34 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139607525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Retracted: “A heterogeneous analysis of the nexus between energy consumption, economic growth and carbon emissions: Evidence from the Group of Twenty (G20) countries”","authors":"","doi":"10.1177/01445987231223919","DOIUrl":"https://doi.org/10.1177/01445987231223919","url":null,"abstract":"","PeriodicalId":444405,"journal":{"name":"Energy Exploration &amp; Exploitation","volume":"19 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139610001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}