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A systematic machine learning method for reservoir identification and production prediction 被引量:3
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作者 Wei Liu Zhangxin Chen +1 位作者 Yuan Hu Liuyang Xu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期295-308,共14页
Reservoir identification and production prediction are two of the most important tasks in petroleum exploration and development.Machine learning(ML)methods are used for petroleum-related studies,but have not been appl... Reservoir identification and production prediction are two of the most important tasks in petroleum exploration and development.Machine learning(ML)methods are used for petroleum-related studies,but have not been applied to reservoir identification and production prediction based on reservoir identification.Production forecasting studies are typically based on overall reservoir thickness and lack accuracy when reservoirs contain a water or dry layer without oil production.In this paper,a systematic ML method was developed using classification models for reservoir identification,and regression models for production prediction.The production models are based on the reservoir identification results.To realize the reservoir identification,seven optimized ML methods were used:four typical single ML methods and three ensemble ML methods.These methods classify the reservoir into five types of layers:water,dry and three levels of oil(I oil layer,II oil layer,III oil layer).The validation and test results of these seven optimized ML methods suggest the three ensemble methods perform better than the four single ML methods in reservoir identification.The XGBoost produced the model with the highest accuracy;up to 99%.The effective thickness of I and II oil layers determined during the reservoir identification was fed into the models for predicting production.Effective thickness considers the distribution of the water and the oil resulting in a more reasonable production prediction compared to predictions based on the overall reservoir thickness.To validate the superiority of the ML methods,reference models using overall reservoir thickness were built for comparison.The models based on effective thickness outperformed the reference models in every evaluation metric.The prediction accuracy of the ML models using effective thickness were 10%higher than that of reference model.Without the personal error or data distortion existing in traditional methods,this novel system realizes rapid analysis of data while reducing the time required to resolve reservoir classification and production prediction challenges.The ML models using the effective thickness obtained from reservoir identification were more accurate when predicting oil production compared to previous studies which use overall reservoir thickness. 展开更多
关键词 Reservoir identification production prediction Machine learning Ensemble method
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Hybrid data-driven framework for shale gas production performance analysis via game theory, machine learning, and optimization approaches 被引量:2
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作者 Jin Meng Yu-Jie Zhou +4 位作者 Tian-Rui Ye Yi-Tian Xiao Ya-Qiu Lu Ai-Wei Zheng Bang Liang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期277-294,共18页
A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis ca... A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis can be challenging because production performance is dominated by the complex interaction among a series of geological and engineering factors.In fact,each factor can be viewed as a player who makes cooperative contributions to the production payoff within the constraints of physical laws and models.Inspired by the idea,we propose a hybrid data-driven analysis framework in this study,where the contributions of dominant factors are quantitatively evaluated,the productions are precisely forecasted,and the development optimization suggestions are comprehensively generated.More specifically,game theory and machine learning models are coupled to determine the dominating geological and engineering factors.The Shapley value with definite physical meaning is employed to quantitatively measure the effects of individual factors.A multi-model-fused stacked model is trained for production forecast,which provides the basis for derivative-free optimization algorithms to optimize the development plan.The complete workflow is validated with actual production data collected from the Fuling shale gas field,Sichuan Basin,China.The validation results show that the proposed procedure can draw rigorous conclusions with quantified evidence and thereby provide specific and reliable suggestions for development plan optimization.Comparing with traditional and experience-based approaches,the hybrid data-driven procedure is advanced in terms of both efficiency and accuracy. 展开更多
关键词 Shale gas production performance DATA-DRIVEN Dominant factors Game theory Machine learning Derivative-free optimization
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Production Capacity Prediction Method of Shale Oil Based on Machine Learning Combination Model
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作者 Qin Qian Mingjing Lu +3 位作者 Anhai Zhong Feng Yang Wenjun He Min Li 《Energy Engineering》 EI 2024年第8期2167-2190,共24页
The production capacity of shale oil reservoirs after hydraulic fracturing is influenced by a complex interplay involving geological characteristics,engineering quality,and well conditions.These relationships,nonlinea... The production capacity of shale oil reservoirs after hydraulic fracturing is influenced by a complex interplay involving geological characteristics,engineering quality,and well conditions.These relationships,nonlinear in nature,pose challenges for accurate description through physical models.While field data provides insights into real-world effects,its limited volume and quality restrict its utility.Complementing this,numerical simulation models offer effective support.To harness the strengths of both data-driven and model-driven approaches,this study established a shale oil production capacity prediction model based on a machine learning combination model.Leveraging fracturing development data from 236 wells in the field,a data-driven method employing the random forest algorithm is implemented to identify the main controlling factors for different types of shale oil reservoirs.Through the combination model integrating support vector machine(SVM)algorithm and back propagation neural network(BPNN),a model-driven shale oil production capacity prediction model is developed,capable of swiftly responding to shale oil development performance under varying geological,fluid,and well conditions.The results of numerical experiments show that the proposed method demonstrates a notable enhancement in R2 by 22.5%and 5.8%compared to singular machine learning models like SVM and BPNN,showcasing its superior precision in predicting shale oil production capacity across diverse datasets. 展开更多
关键词 Shale oil production capacity data-driven model model-driven method machine learning
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Exploration into the Development of"Integration of Production and Education"in Vocational Education in China
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作者 Jialiang HAN Zhen WANG 《Agricultural Biotechnology》 2024年第4期46-49,56,共5页
In order to further clarify the function and important value of the integration of production and education for the development of vocational education,this paper combed the development context of the integration of p... In order to further clarify the function and important value of the integration of production and education for the development of vocational education,this paper combed the development context of the integration of production and education in China's vocational education from three dimensions:policy evolution,research evolution and practice promotion.Studies have shown that the integration of production and education,as a distinctive type characteristic of vocational education in China,has experienced four stages of evolution in policy:the period of combination of production and education,the preparation and presentation period,the full implementation period and the in-depth promotion period,and the initially-constructed institutional system reflects developmental characteristics.In academic research,there are obvious policy-driven characteristics.The theoretical framework tends to be perfect,and the concept connotation and promotion path are gradually getting clear,but the research on regional promotion modes is slightly insufficient.The empirical research is weak,and the operability of countermeasure research is not strong.Moreover,the problem of discussing integration based on education is more prominent.In practice and promotion,the characteristic of the integration of production and education is gradually highlighted and deepened in terms of talent training,school-running system and school-running mode,and the carriers and contents of the integration of production and education are gradually enriched. 展开更多
关键词 Integration of production and education Policy evolution research evolution Practice promotion
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Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty 被引量:1
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作者 Zhong-Zheng Wang Kai Zhang +6 位作者 Guo-Dong Chen Jin-Ding Zhang Wen-Dong Wang Hao-Chen Wang Li-Ming Zhang Xia Yan Jun Yao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期261-276,共16页
Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery substantially.While existing methods could produce high-optimality r... Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery substantially.While existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational demands.In addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical deployment.In this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under uncertainty.Specifically,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified goals.To deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent redundancy.Compared with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown changes.The trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir states.Simulation results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity. 展开更多
关键词 production optimization Deep reinforcement learning Evolutionary algorithm Real-time optimization Optimization under uncertainty
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Data-driven production optimization using particle swarm algorithm based on the ensemble-learning proxy model
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作者 Shu-Yi Du Xiang-Guo Zhao +4 位作者 Chi-Yu Xie Jing-Wei Zhu Jiu-Long Wang Jiao-Sheng Yang Hong-Qing Song 《Petroleum Science》 SCIE EI CSCD 2023年第5期2951-2966,共16页
Production optimization is of significance for carbonate reservoirs,directly affecting the sustainability and profitability of reservoir development.Traditional physics-based numerical simulations suffer from insuffic... Production optimization is of significance for carbonate reservoirs,directly affecting the sustainability and profitability of reservoir development.Traditional physics-based numerical simulations suffer from insufficient calculation accuracy and excessive time consumption when performing production optimization.We establish an ensemble proxy-model-assisted optimization framework combining the Bayesian random forest(BRF)with the particle swarm optimization algorithm(PSO).The BRF method is implemented to construct a proxy model of the injectioneproduction system that can accurately predict the dynamic parameters of producers based on injection data and production measures.With the help of proxy model,PSO is applied to search the optimal injection pattern integrating Pareto front analysis.After experimental testing,the proxy model not only boasts higher prediction accuracy compared to deep learning,but it also requires 8 times less time for training.In addition,the injection mode adjusted by the PSO algorithm can effectively reduce the gaseoil ratio and increase the oil production by more than 10% for carbonate reservoirs.The proposed proxy-model-assisted optimization protocol brings new perspectives on the multi-objective optimization problems in the petroleum industry,which can provide more options for the project decision-makers to balance the oil production and the gaseoil ratio considering physical and operational constraints. 展开更多
关键词 production optimization Random forest The Bayesian algorithm Ensemble learning Particle swarm optimization
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Application of Deep Learning to Production Forecasting in Intelligent Agricultural Product Supply Chain
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作者 Xiao Ya Ma Jin Tong +3 位作者 Fei Jiang Min Xu Li Mei Sun Qiu Yan Chen 《Computers, Materials & Continua》 SCIE EI 2023年第3期6145-6159,共15页
Production prediction is an important factor influencing the realization of an intelligent agricultural supply chain.In an Internet of Things(IoT)environment,accurate yield prediction is one of the prerequisites for a... Production prediction is an important factor influencing the realization of an intelligent agricultural supply chain.In an Internet of Things(IoT)environment,accurate yield prediction is one of the prerequisites for achieving an efficient response in an intelligent agricultural supply chain.As an example,this study applied a conventional prediction method and deep learning prediction model to predict the yield of a characteristic regional fruit(the Shatian pomelo)in a comparative study.The root means square error(RMSE)values of regression analysis,exponential smoothing,grey prediction,grey neural network,support vector regression(SVR),and long short-term memory(LSTM)neural network methods were 53.715,6.707,18.440,1.580,and 1.436,respectively.Among these,the mean square error(MSE)values of the grey neural network,SVR,and LSTM neural network methods were 2.4979,31.652,and 2.0618,respectively;and theirRvalues were 0.99905,0.94,and 0.94501,respectively.The results demonstrated that the RMSE of the deep learning model is generally lower than that of a traditional prediction model,and the prediction results are more accurate.The prediction performance of the grey neural network was shown to be superior to that of SVR,and LSTM neural network,based on the comparison of parameters. 展开更多
关键词 Internet of things intelligent agricultural supply chain deep learning production prediction
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Optimal production lot sizing model in a supply chain with periodically fixed demand considering learning effect 被引量:1
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作者 熊中楷 SHEN Tiesong 《Journal of Chongqing University》 CAS 2002年第2期86-88,共3页
This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find t... This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find the optimal delay time for production and production time sequentially. It is found that the optimal delay time for production and the production time are not static, but dynamic and variant with time. It is important for a manufacturer to schedule the production so as to prevent facilities and workers from idling. 展开更多
关键词 learning curve capacity expansion supply chain optimal production policy.
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Better use of experience from other reservoirs for accurate production forecasting by learn-to-learn method
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作者 Hao-Chen Wang Kai Zhang +7 位作者 Nancy Chen Wen-Sheng Zhou Chen Liu Ji-Fu Wang Li-Ming Zhang Zhi-Gang Yu Shi-Ti Cui Mei-Chun Yang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期716-728,共13页
To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studie... To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studied to make predictions accurate.However,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same class.This results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar reservoirs.This paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various reservoirs.Intuitively,the proposed method first learns how to learn samples before directly learning rules in samples.Technically,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different classes.Based on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same class.Two cases further demonstrate its superiority in accuracy to other widely-used network methods. 展开更多
关键词 production forecasting Multiple patterns Few-shot learning Transfer learning
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Multi-surrogate framework with an adaptive selection mechanism for production optimization
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作者 Jia-Lin Wang Li-Ming Zhang +10 位作者 Kai Zhang Jian Wang Jian-Ping Zhou Wen-Feng Peng Fa-Liang Yin Chao Zhong Xia Yan Pi-Yang Liu Hua-Qing Zhang Yong-Fei Yang Hai Sun 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期366-383,共18页
Data-driven surrogate models that assist with efficient evolutionary algorithms to find the optimal development scheme have been widely used to solve reservoir production optimization problems.However,existing researc... Data-driven surrogate models that assist with efficient evolutionary algorithms to find the optimal development scheme have been widely used to solve reservoir production optimization problems.However,existing research suggests that the effectiveness of a surrogate model can vary depending on the complexity of the design problem.A surrogate model that has demonstrated success in one scenario may not perform as well in others.In the absence of prior knowledge,finding a promising surrogate model that performs well for an unknown reservoir is challenging.Moreover,the optimization process often relies on a single evolutionary algorithm,which can yield varying results across different cases.To address these limitations,this paper introduces a novel approach called the multi-surrogate framework with an adaptive selection mechanism(MSFASM)to tackle production optimization problems.MSFASM consists of two stages.In the first stage,a reduced-dimensional broad learning system(BLS)is used to adaptively select the evolutionary algorithm with the best performance during the current optimization period.In the second stage,the multi-objective algorithm,non-dominated sorting genetic algorithm II(NSGA-II),is used as an optimizer to find a set of Pareto solutions with good performance on multiple surrogate models.A novel optimal point criterion is utilized in this stage to select the Pareto solutions,thereby obtaining the desired development schemes without increasing the computational load of the numerical simulator.The two stages are combined using sequential transfer learning.From the two most important perspectives of an evolutionary algorithm and a surrogate model,the proposed method improves adaptability to optimization problems of various reservoir types.To verify the effectiveness of the proposed method,four 100-dimensional benchmark functions and two reservoir models are tested,and the results are compared with those obtained by six other surrogate-model-based methods.The results demonstrate that our approach can obtain the maximum net present value(NPV)of the target production optimization problems. 展开更多
关键词 production optimization Multi-surrogate models Multi-evolutionary algorithms Dimension reduction Broad learning system
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Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines
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作者 Chengkai Fan Na Zhang +1 位作者 Bei Jiang Wei Victor Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期727-740,共14页
Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challe... Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challenging when training data(e.g.truck haulage information and weather conditions)are massive.In machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden layers.This study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training data.Before the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input variables.To verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark models.The DNN model with multiple hidden layers performed better than the ANN models with a single hidden layer.The DNN model outperformed the extensively applied benchmark models in predicting ore production.This can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines. 展开更多
关键词 Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering
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Production performance forecasting method based on multivariate time series and vector autoregressive machine learning model for waterflooding reservoirs
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作者 ZHANG Rui JIA Hu 《Petroleum Exploration and Development》 CSCD 2021年第1期201-211,共11页
A forecasting method of oil well production based on multivariate time series(MTS)and vector autoregressive(VAR)machine learning model for waterflooding reservoir is proposed,and an example application is carried out.... A forecasting method of oil well production based on multivariate time series(MTS)and vector autoregressive(VAR)machine learning model for waterflooding reservoir is proposed,and an example application is carried out.This method first uses MTS analysis to optimize injection and production data on the basis of well pattern analysis.The oil production of different production wells and water injection of injection wells in the well group are regarded as mutually related time series.Then a VAR model is established to mine the linear relationship from MTS data and forecast the oil well production by model fitting.The analysis of history production data of waterflooding reservoirs shows that,compared with history matching results of numerical reservoir simulation,the production forecasting results from the machine learning model are more accurate,and uncertainty analysis can improve the safety of forecasting results.Furthermore,impulse response analysis can evaluate the oil production contribution of the injection well,which can provide theoretical guidance for adjustment of waterflooding development plan. 展开更多
关键词 waterflooding reservoir production prediction machine learning multivariate time series vector autoregression uncertainty analysis
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Teaching Reform Path of Architecture Specialty under the Collaborative Education of “Production, Teaching and Research” and Its Application Effect
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作者 WANG Jiang ZHANG Guofeng WANG Shuyang 《Journal of Landscape Research》 2021年第5期100-102,共3页
To break through the development bottleneck of architecture specialty,it should think about how to realize the high-quality cultivation of talents through the adjustment of teaching system.Reform path of architecture ... To break through the development bottleneck of architecture specialty,it should think about how to realize the high-quality cultivation of talents through the adjustment of teaching system.Reform path of architecture under the collaborative education of "production,teaching and research" and its application effect are systemically studied.By analyzing the relationship among production,teaching and scientific research,the essence of integration and mutual assistance among the three is analyzed.A series of teaching reforms are carried out on the reform principles of teaching content,setting principles of practice curriculum and implementation paths of practice curriculum in the theoretical and practical courses of architecture specialty.The purpose is to make the achievements of scientific research and production contribute to the development of teaching,so that the three sections of "production,teaching and research" form a benign interaction,mutual assistance and common promotion.This teaching system under the collaborative education of "production,teaching and research" is of positive significance to the cultivation of architectural talents’ innovative ability,practical ability and comprehensive ability. 展开更多
关键词 production teaching and research Collaborative education Reform path Application effect
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Research Progress on Mechanized Mixed Sowing Seed Production Technology of Hybrid Rice 被引量:4
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作者 张德文 《Agricultural Science & Technology》 CAS 2017年第5期924-929,939,共7页
Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The resea... Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The research progress on mixed sowing seed production techniques of hybrid rice was introduced from the aspects of rice resources creation, breeding, sowing seed technology research and cost benefit analysis. The production technology of the new mixed seeding combina- tion "Xinhunyou 6" was investigated, including the research and validation of benta- zon treatment period and dosage, mixing ratio of male and female parents, and the comparative test of different different sowing methods, which revealed that the mechanization technology of seed production of hybrid rice was mature and feasible and would be one of the most important development trend of technological devel- opment of hybrid rice production. 展开更多
关键词 Hybrid rice Mechanized seed production Glume color marker gene BENTAZON research progress
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Optimizing Teacher-Student Collaborative Assessment in the Production-Oriented Approach:A Dialectical Research 被引量:10
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作者 Shuguang SUN 《Chinese Journal of Applied Linguistics》 2020年第3期305-322,388,389,共20页
Teacher-student collaborative assessment(TSCA)aims to address the challenges of responding to students’work in the Production-Oriented Approach:low efficiency and poor effectiveness.As part of a bigger project carrie... Teacher-student collaborative assessment(TSCA)aims to address the challenges of responding to students’work in the Production-Oriented Approach:low efficiency and poor effectiveness.As part of a bigger project carried out in a Chinese university over a period of three years,the present study explored how the teacher prepared and implemented TSCA in class,especially with a focus on how she determined the assessing objective and worked collaboratively with her students in class to achieve it,using the students’written and translated texts as examples.By adopting the dialectical research(DR)method,this paper collected qualitative data such as teaching plans,classroom recordings,and reflective journals of the teacher-researcher(the author),along with students’written drafts and translated texts.TSCA theory and classroom practice have been refined simultaneously by means of putting theory into practice and reflecting upon it.The optimized pre-class and in-class procedures may shed some light on applying TSCA to L2 classrooms. 展开更多
关键词 teacher-student collaborative assessment(TSCA) writing assessment production-Oriented Approach(POA) dialectical research(DR) assessment being learning
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A Comparison of Chinese, Japanese, and Korean shipyard production technology 被引量:2
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作者 BAI Xue-ping NIE Wu LIU Cheng-ming 《Journal of Marine Science and Application》 2007年第2期25-29,共5页
This paper compares Chinese, Korean, and Japanese shipyard production technology. Development in the world shipbuilding over recent years has influenced focus areas related to shipyard manufacturing technologies and p... This paper compares Chinese, Korean, and Japanese shipyard production technology. Development in the world shipbuilding over recent years has influenced focus areas related to shipyard manufacturing technologies and product performance. Software systems, information technology, production technology, and local challenges of shipyards are compared with shipbuilding outputs among these three countries. Various technologies developments, shipyard production and the problems in Chinese, Japanese, and Korean shipyards are discussed respectively. Finally, future areas of research are pointed out. 展开更多
关键词 shipyard production manufacturing technologies software systems shipbuilding output future researches
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Zhang Weishe n:A Pion eer in the Developme nt and In dustrial Production of Penicillin in New China 被引量:1
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作者 Bin Yu Fumin Huang +1 位作者 Guoxing Tang Jing Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第3期282-286,I0015,共6页
The research and development of penicillin started with dificulty before 1949 and achieved certain results.In 1951,after the founding of the People’ s Republic of China,Zhang Weishen,as the only Chinese scientist who... The research and development of penicillin started with dificulty before 1949 and achieved certain results.In 1951,after the founding of the People’ s Republic of China,Zhang Weishen,as the only Chinese scientist who had been trained and worked in a penicillin research and development center in the United States for many years,overcame many difficulties and returned to China.In 1953,with the efforts of Zhang Weishen and his colleagues,China realized the industrialized production of penicillin,alleviating the urgent needs of the masses.Antibiotics has also become the first discipline to achieve major scientific and technological achievements after the founding of the New China.In the mid-1950s,the technical breakthrough in the localization of lactose substitutes marked the localization of the raw materials of the penicillin-producing culture medium,which paved the way for the industrialized production of penicillin with Chinese characteristics.Antibiotics have become one of the most widely used and affordable drugs for hundreds of millions of patients in China,and China has since ended the humiliating history of the "Sick Man of East Asia". 展开更多
关键词 PENICILLIN ANTIBIOTICS research and development industrial production Zhang Weishen
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Deep-Learning-Based Production Decline Curve Analysis in the Gas Reservoir through Sequence Learning Models
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作者 Shaohua Gu Jiabao Wang +3 位作者 Liang Xue Bin Tu Mingjin Yang Yuetian Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1579-1599,共21页
Production performance prediction of tight gas reservoirs is crucial to the estimation of ultimate recovery,which has an important impact on gas field development planning and economic evaluation.Owing to the model’s... Production performance prediction of tight gas reservoirs is crucial to the estimation of ultimate recovery,which has an important impact on gas field development planning and economic evaluation.Owing to the model’s simplicity,the decline curve analysis method has been widely used to predict production performance.The advancement of deep-learning methods provides an intelligent way of analyzing production performance in tight gas reservoirs.In this paper,a sequence learning method to improve the accuracy and efficiency of tight gas production forecasting is proposed.The sequence learning methods used in production performance analysis herein include the recurrent neural network(RNN),long short-term memory(LSTM)neural network,and gated recurrent unit(GRU)neural network,and their performance in the tight gas reservoir production prediction is investigated and compared.To further improve the performance of the sequence learning method,the hyperparameters in the sequence learning methods are optimized through a particle swarm optimization algorithm,which can greatly simplify the optimization process of the neural network model in an automated manner.Results show that the optimized GRU and RNN models have more compact neural network structures than the LSTM model and that the GRU is more efficiently trained.The predictive performance of LSTM and GRU is similar,and both are better than the RNN and the decline curve analysis model and thus can be used to predict tight gas production. 展开更多
关键词 Tight gas production forecasting deep learning sequence learning models
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Research Progress of Application of Microbial Inoculants in Agricultural Production
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作者 Yunyun ZHOU Yating XIE +3 位作者 Xiu LIU Kaifa GUO Chenzhong JIN Shunli XIAO 《Agricultural Biotechnology》 CAS 2020年第4期155-158,共4页
Microbial inoculants have received increasing attention in strengthening plant biological barriers,antagonizing and inhibiting harmful microorganisms,and ensuring the safe production of agricultural products.This pape... Microbial inoculants have received increasing attention in strengthening plant biological barriers,antagonizing and inhibiting harmful microorganisms,and ensuring the safe production of agricultural products.This paper summarized the research status of agricultural microbial inoculants,the application of microbial inoculants in agriculture,and the trends and prospects of agricultural microbial research. 展开更多
关键词 Microbial inoculants Agricultural production research progress
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Studies on Production Planning of Dispersion Type U3Si2-Al Fuel in Plate-Type Fuel Elements for Nuclear Research Reactors
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作者 Miguel Luiz Miotto Negro Michelangelo Durazzo +2 位作者 Marco Aurélio de Mesquita Elita Fontenele Urano de Carvalho Delvonei Alves de Andrade 《World Journal of Nuclear Science and Technology》 2016年第4期217-231,共16页
Several fuel plants that supply nuclear research reactors need to increase their production capacity in order to meet the growing demand for this kind of nuclear fuel. After the enlargement of the production capacity ... Several fuel plants that supply nuclear research reactors need to increase their production capacity in order to meet the growing demand for this kind of nuclear fuel. After the enlargement of the production capacity of such plants, there will be the need of managing the new production level. That level is usually the industrial one, which poses challenges to the managerial staff. Such challenges come from the fact that several of those plants operate today on a laboratorial basis and do not carry inventory. The change to the industrial production pace asks for new actions regarding planning and control. The production process based on the hydrolysis of UF6 is not a frequent production route for nuclear fuel. Production planning and control of the industrial level of fuel production on that production route is a new field of studies. The approach of the paper consists in the creation of a mathematical linear model for minimization of costs. We also carried out a sensitivity analysis of the model. The results help in minimizing costs in different production schemes and show the need of inventory. The mathematical model is dynamic, so that it issues better results if performed monthly. The management team will therefore have a clearer view of the costs and of the new, necessary production and inventory levels. 展开更多
关键词 Fabrication of Uranium Silicide Fuel Nuclear research Reactors production Planning and Control
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