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Investigation into the Methodology and Implementation of Life Cycle Engineering under China’s Carbon Reduction Target in the Process Industry
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作者 Mingyang Li Feng Gao +3 位作者 Zuoren Nie Boxue Sun Yu Liu Xianzheng Gong 《Engineering》 SCIE EI CAS CSCD 2024年第9期87-99,共13页
The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achie... The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production. 展开更多
关键词 Carbon neutrality Life cycle engineering process industry Carbon reduction technology ECO-DESIGN
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Detection of Oscillations in Process Control Loops From Visual Image Space Using Deep Convolutional Networks
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作者 Tao Wang Qiming Chen +3 位作者 Xun Lang Lei Xie Peng Li Hongye Su 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期982-995,共14页
Oscillation detection has been a hot research topic in industries due to the high incidence of oscillation loops and their negative impact on plant profitability.Although numerous automatic detection techniques have b... Oscillation detection has been a hot research topic in industries due to the high incidence of oscillation loops and their negative impact on plant profitability.Although numerous automatic detection techniques have been proposed,most of them can only address part of the practical difficulties.An oscillation is heuristically defined as a visually apparent periodic variation.However,manual visual inspection is labor-intensive and prone to missed detection.Convolutional neural networks(CNNs),inspired by animal visual systems,have been raised with powerful feature extraction capabilities.In this work,an exploration of the typical CNN models for visual oscillation detection is performed.Specifically,we tested MobileNet-V1,ShuffleNet-V2,Efficient Net-B0,and GhostNet models,and found that such a visual framework is well-suited for oscillation detection.The feasibility and validity of this framework are verified utilizing extensive numerical and industrial cases.Compared with state-of-theart oscillation detectors,the suggested framework is more straightforward and more robust to noise and mean-nonstationarity.In addition,this framework generalizes well and is capable of handling features that are not present in the training data,such as multiple oscillations and outliers. 展开更多
关键词 Convolutional neural networks(CNNs) deep learning image processing oscillation detection process industries
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An embedded lightweight GUI component library and ergonomics optimization method for industry process monitoring 被引量:1
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作者 Da-peng TAN Shu-ting CHEN +1 位作者 Guan-jun BAO Li-bin ZHANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2018年第5期604-625,共22页
Developing an efficient and robust lightweight graphic user interface (GUI) for industry process monitoring is always a challenging task. Current implementation methods for embedded GUI are with the matters of real-... Developing an efficient and robust lightweight graphic user interface (GUI) for industry process monitoring is always a challenging task. Current implementation methods for embedded GUI are with the matters of real-time processing and ergonomics performance. To address the issue, an embedded lightweight GUI component library design method based on quasar technology embedded (Qt/E) is proposed. First, an entity-relationship (E-R) model for the GUI library is developed to define the functional framework and data coupling relations. Second, a cross-compilation environment is constructed, and the QI/E shared library files are tailored to satisfy the requirements of embedded target systems. Third, by using the signal-slot communication interfaces, a message mapping mechanism that does not require a call-back pointer is developed, and the context switching performance is improved. According to the multi-thread method, the parallel task processing capabilities fbr data collection, calculation, and display are enhanced, and the real-time performance and robustness are guaranteed. Finally, the human-computer interaction process is optimized by a scrolling page method, and the ergonomics pertbrmance is verified by the industrial psychology methods Two numerical cases and five industrial experiments show that the proposed method can increase real-time read-write correction ratios by more than 26% and 29%, compared with Windows-CE-GUl and Android-GUl, respectively. The component library can be tailored to 900 KB and supports 12 hardware platforms. The average session switch time can be controlled within 0.6 s and six key indexes for ergonomics are verified by different industrial applications. 展开更多
关键词 Embedded lightweight graphic user interface (GUI) Quasar technology embedded (Qt/E) industry process moni-toring MULTI-THREAD Ergonomics performance
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Intelligent Manufacturing for the Process Industry Driven by Industrial Artificial Intelligence 被引量:20
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作者 Tao Yang Xinlei Yi +2 位作者 Shaowen Lu Karl HJohansson Tianyou Chai 《Engineering》 SCIE EI 2021年第9期1224-1230,共7页
Based on the analysis of the characteristics and operation status of the process industry,as well as the development of the global intelligent manufacturing industry,a new mode of intelligent manufacturing for the pro... Based on the analysis of the characteristics and operation status of the process industry,as well as the development of the global intelligent manufacturing industry,a new mode of intelligent manufacturing for the process industry,namely,deep integration of industrial artificial intelligence and the Industrial Internet with the process industry,is proposed.This paper analyzes the development status of the existing three-tier structure of the process industry,which consists of the enterprise resource planning,the manufacturing execution system,and the process control system,and examines the decision-making,control,and operation management adopted by process enterprises.Based on this analysis,it then describes the meaning of an intelligent manufacturing framework and presents a vision of an intelligent optimal decision-making system based on human–machine cooperation and an intelligent autonomous control system.Finally,this paper analyzes the scientific challenges and key technologies that are crucial for the successful deployment of intelligent manufacturing in the process industry. 展开更多
关键词 Industrial artificial intelligence Industrial Internet Intelligent manufacturing process industry
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Opportunities and Challenges of Artificial Intelligence for Green Manufacturing in the Process Industry 被引量:15
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作者 Shuai Mao Bing Wang +1 位作者 Yang Tang Feng Qian 《Engineering》 SCIE EI 2019年第6期995-1002,共8页
Smart manufacturing is critical in improving the quality of the process industry. In smart manufacturing, there is a trend to incorporate different kinds of new-generation information technologies into process- safety... Smart manufacturing is critical in improving the quality of the process industry. In smart manufacturing, there is a trend to incorporate different kinds of new-generation information technologies into process- safety analysis. At present, green manufacturing is facing major obstacles related to safety management, due to the usage of large amounts of hazardous chemicals, resulting in spatial inhomogeneity of chemical industrial processes and increasingly stringent safety and environmental regulations. Emerging informa- tion technologies such as arti cial intelligence (AI) are quite promising as a means of overcoming these dif culties. Based on state-of-the-art AI methods and the complex safety relations in the process industry, we identify and discuss several technical challenges associated with process safety: ① knowledge acquisition with scarce labels for process safety;② knowledge-based reasoning for process safety;③ accurate fusion of heterogeneous data from various sources;and ④ effective learning for dynamic risk assessment and aided decision-making. Current and future works are also discussed in this context. 展开更多
关键词 process industry Smart manufacturing Green manufacturing Artificial intelligence
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Operational Performance Evaluation of Corn Processing Industry Technological Innovation Alliance Based on Survey Data in Heilongjiang Province
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作者 Zhang Xiao-mei Zhang Jia-xin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第1期85-96,共12页
This paper selected the corn processing industry technology innovation alliance in Heilongjiang Province as the research object, evaluated the operational performance of the alliance by using analytic hierarchy proces... This paper selected the corn processing industry technology innovation alliance in Heilongjiang Province as the research object, evaluated the operational performance of the alliance by using analytic hierarchy process(AHP) and fuzzy comprehensive evaluation methods. AHP empirical results showed that the satisfaction of information communication and the satisfaction of the management process were the weakest. And the order from high to low on the level of indicators of the impact for the alliance was the result of alliance operations and the process of alliance operations, the behavioral attitude of alliance members. Besides, the results of fuzzy comprehensive evaluation showed that the operational performance of the corn processing industry technology innovation alliance in Heilongjiang Province was in the general level. 展开更多
关键词 corn processing industry technology innovation strategic alliance operational performance
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Development Situation and Strategy Analysis of Waxy Corn Processing Industry in Chongqing Municipality
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作者 Yuan WU Lijun GAO Bo LI 《Asian Agricultural Research》 2018年第2期42-45,共4页
With the development of society and economy and increasing awareness of people's diet and health care,the demand for waxy corn and its processed products has been rising. At present,the planting of waxy corn in Ch... With the development of society and economy and increasing awareness of people's diet and health care,the demand for waxy corn and its processed products has been rising. At present,the planting of waxy corn in Chongqing is taking shape,but the waxy corn processing is still in the initial stage with smaller enterprise scale and fewer processing product variety. Based on the analysis of the development advantages and disadvantages of waxy corn processing industry in Chongqing,this paper brings forward the development ideas and strategies of Chongqing waxy corn processing industry from three aspects of production,processing and policy. 展开更多
关键词 Waxy corn processing industry Circular economy Policy support Chongqing Municipality
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Factor and Cluster Analysis on the Competitiveness of Agri-food Processing Industry in China
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作者 Ling WANG 《Asian Agricultural Research》 2017年第2期1-5,共5页
This paper establishes 13 evaluation indicators for the competitiveness of agri-food processing industry,uses factor analysis to evaluate the competitiveness of agri-food processing industry in 31 provinces(cities,aut... This paper establishes 13 evaluation indicators for the competitiveness of agri-food processing industry,uses factor analysis to evaluate the competitiveness of agri-food processing industry in 31 provinces(cities,autonomous regions)of China,and does cluster analysis to divide these regions into several categories according to the difference in competitiveness,in order to understand the level of competitiveness of agri-food processing industry in China. 展开更多
关键词 Agri-food processing industry COMPETITIVENESS Factor analysis Cluster analysis
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Analysis on Development Characteristics of Agricultural Product Processing Industry under the New Normal
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作者 Jianhua Zhao Ligui Chen Peixiong Zhang 《Plant Diseases and Pests》 CAS 2021年第5期35-38,共4页
From the beginning of the 21^(st)century to 2013,the economic income of main business of agricultural products processing enterprises in China had maintained above double digits for a long time.The current traditional... From the beginning of the 21^(st)century to 2013,the economic income of main business of agricultural products processing enterprises in China had maintained above double digits for a long time.The current traditional high-speed growth will be transformed to high-quality,mediumhigh-speed development,and the development trend is in line with economic laws and macro situation characteristics.With the acceleration of spa-tial distribution and cluster development of agricultural processing industry,the late-mover advantages in the central and western regions of China are gradually emerging.With the support of Internet+and e-commerce online shopping platforms,the integrative development with related industries has been deepened.Led by the new concept of green development,the demand of processing industry of green,healthy,specific functional food(such as diabetes,hypertension and other specific groups)is booming.In the aspect of development strategy,it is appropriate to build multivariate information service platform,improve the technical cooperation platform,and provide software and hardware facilities for further development of agricultural product processing industry.Combined with local economic development advantages,resource advantages and industrial advantages and other factors,the way of differentiation,regionalization and characterization should be taken according to local conditions and following the law,so as to energize the rural revitalization. 展开更多
关键词 Agricultural product processing industry Development strategy
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Study on Innovation System and Innovation Strategy of Chinese Agricultural Product Processing Industry
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作者 Min Wang Mingyu Zhang Lihua Guo 《Chinese Business Review》 2003年第2期33-45,77,共14页
The agricultural product processing industry is the inevitable choice for the agriculture to realize the industrialization, integration and modernization. Although the agricultural product processing industry has beco... The agricultural product processing industry is the inevitable choice for the agriculture to realize the industrialization, integration and modernization. Although the agricultural product processing industry has become the bright point in Chinese economy development, the whole development level falls behind the developed countries. The thesis brings up that the inherent reasons that Chinese agricultural product processing industry falls behind is that Chinese agricultural product processing industry has not an integrated industrial innovation system and has not a proper innovation strategy. So this thesis deeply discusses how to construct innovation system of Chinese agricultural product processing industry and puts forward the innovation strategy in order to improve the technology innovation capability and the development level. 展开更多
关键词 Innovation System Technology stride Agricultural product processing industry
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Industrial Recycling Process of Batteries for EVs
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作者 Abdallah Abdallah Muhamed Dauwed +3 位作者 Ayman A.Aly Bassem F.Felemban Imran Khan DagФivind Madsen 《Computers, Materials & Continua》 SCIE EI 2023年第2期4571-4586,共16页
The growing number of decarbonization standards in the transportation sector has resulted in an increase in demand for electric cars.Renewable energy sources have the ability to bring the fossil fuel age to an end.Ele... The growing number of decarbonization standards in the transportation sector has resulted in an increase in demand for electric cars.Renewable energy sources have the ability to bring the fossil fuel age to an end.Electrochemical storage devices,particularly lithium-ion batteries,are critical for this transition’s success.This is owing to a combination of favorable characteristics such as high energy density and minimal self-discharge.Given the environmental degradation caused by hazardous wastes and the scarcity of some resources,recycling used lithium-ion batteries has significant economic and practical importance.Many efforts have been undertaken in recent years to recover cathode materials(such as high-value metals like cobalt,nickel,and lithium).Regrettably,the regeneration of lower-value-added anode materials(mostly graphite)has received little attention.However,given the widespread use of carbon-based materials and the higher concentration of lithium in the anode than in the environment,anode recycling has gotten a lot of attention.As a result,this article provides the most recent research progress in the recovery of graphite anode materials from spent lithium ion batteries,analyzing the strengths and weaknesses of various recovery routes such as direct physical recovery,heat treatment recovery,hydrometallurgy recovery,heat treatment-hydrometallurgy recovery,extraction,and electrochemical methods from the perspectives of energy,environment,and economy;additionally,the reuse of recycled anode mats is discussed.Finally,the problems and future possibilities of anode recycling are discussed.To enable the green recycling of wasted lithium ion batteries,a low energy-consuming and ecologically friendly solution should be investigated. 展开更多
关键词 Industrial recycling process lithium ion batteries electro-chemical process REMANUFACTURING
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Effective technology for processing industrial volatile organic compounds by the atmospheric pressure microwave plasma torch
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作者 Da-Shuai Li Ling Tong 《Journal of Electronic Science and Technology》 EI CAS CSCD 2023年第2期87-94,共8页
In this study,we investigated the abatement of volatile organic compounds(VOCs)by the atmospheric pressure microwave plasma torch(AMPT).To study the treatment efficiency of AMPT,we used the toluene and water-based var... In this study,we investigated the abatement of volatile organic compounds(VOCs)by the atmospheric pressure microwave plasma torch(AMPT).To study the treatment efficiency of AMPT,we used the toluene and water-based varnish to simulate VOCs,respectively.By measuring the compounds and contents of the mixture gas before/after the microwave plasma process,we have calculated the treatment efficiency of AMPT.The experimental results show that the treatment efficiency of AMPT for toluene with a concentration of 17.32×10^(4) ppm is up to 60 g/kWh with the removal rate of 86%.For the volatile compounds of water-based varnish,the removal efficiency is up to 97.99%.We have demonstrated the higher potential for VOCs removal of the AMPT process. 展开更多
关键词 Atmospheric microwave plasma Industrial volatile organic compounds(VOCs)processing Spectroscopic diagnostic
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Filter-based iterative learning control for linear large-scale industrial processes 被引量:4
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作者 Xiao'eRUAN JianguoWANG BaiwuWAN 《控制理论与应用(英文版)》 EI 2004年第2期149-154,共6页
In the procedure of the steady-state hierarchical optimization with feedback for large-scale industrial processes, a sequence of set-point changes with different magnitudes is carried out on the optimization layer. To... In the procedure of the steady-state hierarchical optimization with feedback for large-scale industrial processes, a sequence of set-point changes with different magnitudes is carried out on the optimization layer. To improve the dynamic performance of transient response driven by the set-point changes, a filter-based iterative learning control strategy is proposed. In the proposed updating law, a local-symmetric-integral operator is adopted for eliminating the measurement noise of output information,a set of desired trajectories are specified according to the set-point changes sequence, the current control input is iteratively achieved by utilizing smoothed output error to modify its control input at previous iteration, to which the amplified coefficients related to the different magnitudes of set-point changes are introduced. The convergence of the algorithm is conducted by incorporating frequency-domain technique into time-domain analysis. Numerical simulation demonstrates the effectiveness of the proposed strategy, 展开更多
关键词 Iterative learning control Large-scale industrial processes Steady-state optimization Dynamic performance
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Rice Drying,Storage and Processing:Effects of Post-Harvest Operations on Grain Quality 被引量:7
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作者 Amanda MÜLLER Marcela Trojahn NUNES +6 位作者 Vanessa MALDANER Paulo Carteri CORADI Rosana Santos de MORAES Samuel MARTENS Andressa Fernandes LEAL Vladison Fogliato PEREIRA Cristielle König MARIN 《Rice science》 SCIE CSCD 2022年第1期16-30,共15页
Various post-harvest processes of rice are commonly employed,especially during the off-season,to ensure its consumption feasibility,which often affect the grain quality.Different forms of drying,storage and processing... Various post-harvest processes of rice are commonly employed,especially during the off-season,to ensure its consumption feasibility,which often affect the grain quality.Different forms of drying,storage and processing of rice are evaluated to identify their effects on grain quality.Microwave drying has emerged as an alternative to the widely-used intermittent-drying and fixed-bed-dryer methods of drying paddy rice.Control of drying-air temperatures(between 40℃ and 60℃)according to the rice variety can improve quality,especially for exotic varieties.Keeping stored grain in hygroscopic balance,with water content between 11%to 15%,at temperatures between 16℃ and 20℃ and with intergranular relative humidity near 60%,allows 12 months of storage in a controlled environment without significant deterioration.Other innovations,notably the application of artificial refrigeration to grain stored in bulk in vertical cylindrical silos and the use of impermeable packaging for storage,ensure the conservation of grain mass.The different stages and equipments used to obtain polished,brown and parboiled rice result in significant changes in the nutritional value of rice because of the removal of the outermost layers of the grains.Polishing reduces the nutritional value and physical homogeneity of rice.Brown rice retains more bioactive compounds and nutrients because it does not lose the outer layer of the grains in the polishing processes.Parboiled rice,although less nutritious than brown rice,has better grain integrity and milling yield and less loss of nutrients than white rice. 展开更多
关键词 agricultural engineering post-harvest rice engineering quality in rice pre-processing rice process industry
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Machine learning based online fault prognostics for nonstationary industrial process via degradation feature extraction and temporal smoothness analysis 被引量:2
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作者 HU Yun-yun ZHAO Chun-hui KE Zhi-wu 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第12期3838-3855,共18页
Fault degradation prognostic, which estimates the time before a failure occurs and process breakdowns, has been recognized as a key component in maintenance strategies nowadays. Fault degradation processes are, in gen... Fault degradation prognostic, which estimates the time before a failure occurs and process breakdowns, has been recognized as a key component in maintenance strategies nowadays. Fault degradation processes are, in general,slowly varying and can be modeled by autoregressive models. However, industrial processes always show typical nonstationary nature, which may bring two challenges: how to capture fault degradation information and how to model nonstationary processes. To address the critical issues, a novel fault degradation modeling and online fault prognostic strategy is developed in this paper. First, a fault degradation-oriented slow feature analysis(FDSFA) algorithm is proposed to extract fault degradation directions along which candidate fault degradation features are extracted. The trend ability assessment is then applied to select major fault degradation features. Second, a key fault degradation factor(KFDF) is calculated to characterize the fault degradation tendency by combining major fault degradation features and their stability weighting factors. After that, a time-varying regression model with temporal smoothness regularization is established considering nonstationary characteristics. On the basis of updating strategy, an online fault prognostic model is further developed by analyzing and modeling the prediction errors. The performance of the proposed method is illustrated with a real industrial process. 展开更多
关键词 fault prognostic NONSTATIONARY industrial process fault degradation-oriented slow feature analysis(FDSFA) temporal smoothness regularization
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Scenario analysis on abating industrial process greenhouse gas emissions from adipic acid production in China 被引量:1
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作者 Qing Tong Han-Yi Lin +3 位作者 Xu-Ying Qin Run-Sheng Yan Yue-Feng Guo Xin-Yang Wei 《Petroleum Science》 SCIE CAS CSCD 2020年第4期1171-1179,共9页
Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate ... Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps.The forecasting method of this paper is consistent with the published national inventory in terms of caliber.Based on the N_2 O abatement technical parameters of adipic acid and the production trend,this paper combines the scenario analysis and provides a measurement of comprehensive N_2 O abatement effect of the entire industry in China.Four future scenarios are assumed.The baseline scenario(BAUS) is a frozen scenario.Three emission abatement scenarios(ANAS,SNAS,and ENAS) are assumed under different strength of abatement driving parameters.The results show that China's adipic acid production process can achieve increasingly significant N_2 O emission abatement effects.Compared to the baseline scenario,by 2030,the N_2 O emission abatements of the three emission abatement scenarios can reach 207-399 kt and the emission abatement ratios can reach 32.5%-62.6%.By 2050,the N_2 O emission abatements for the three emission abatement scenarios can reach 387-540 kt and the emission abatement ratios can reach 71.4%-99.6%. 展开更多
关键词 Scenario analysis Industrial process greenhouse gas emissions Adipic acid N2O emission abatement China
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Generic reconstruction technology based on RST for multivariate time series of complex process industries 被引量:1
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作者 孔玲爽 阳春华 +2 位作者 李建奇 朱红求 王雅琳 《Journal of Central South University》 SCIE EI CAS 2012年第5期1311-1316,共6页
In order to effectively analyse the multivariate time series data of complex process,a generic reconstruction technology based on reduction theory of rough sets was proposed,Firstly,the phase space of multivariate tim... In order to effectively analyse the multivariate time series data of complex process,a generic reconstruction technology based on reduction theory of rough sets was proposed,Firstly,the phase space of multivariate time series was originally reconstructed by a classical reconstruction technology.Then,the original decision-table of rough set theory was set up according to the embedding dimensions and time-delays of the original reconstruction phase space,and the rough set reduction was used to delete the redundant dimensions and irrelevant variables and to reconstruct the generic phase space,Finally,the input vectors for the prediction of multivariate time series were extracted according to generic reconstruction results to identify the parameters of prediction model.Verification results show that the developed reconstruction method leads to better generalization ability for the prediction model and it is feasible and worthwhile for application. 展开更多
关键词 complex process industry prediction model multivariate time series rough sets
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An Investment Decision Support System for Process Industries
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作者 周章玉 成思危 +2 位作者 华贲 曾敏刚 尹清华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第4期402-406,共5页
Most studies on investment evaluation mainly focus on enterprise economic benefits only, without process operability and sustainability considered. In this paper, we suggest that investment evaluation in process indus... Most studies on investment evaluation mainly focus on enterprise economic benefits only, without process operability and sustainability considered. In this paper, we suggest that investment evaluation in process industries should be executed under three strategic objectives--enterprise benefits, social benefits and customer benefits. A systematic investment evaluation and decision-making method with a four-step procedure based on the analytic hierarchy process (AHP) is proposed to evaluate various qualitative and quantitative elements with various criteria. At the first step, the decision hierarchy is constructed under the three strategic objectives. Second, pair-wise comparison is utilized to evaluate the weights of elements and criteria. Third, qualitative elements are quantified by pair-wise comparison and quantitative elements are re-scaled by a uniform criterion. At the last, the best choice is made through synthesizing values upward in the hierarchy. An investment decision support system (DSS) is developed based on Microsoft Excel, and applied to a retrofit investment of united fluid catalytic cracking(FCC) and liquefied gas separation process in a refinery plant. 展开更多
关键词 investment evaluation decision support system process industries analytic hierarchy process
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An Analysis of Development Trend of Food Industry in Three Northeastern Provinces of China
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作者 Wenxin LIU Xiuli HE 《Asian Agricultural Research》 2018年第1期16-20,23,共6页
The food industry has developed into a leading industry in Northeast China.However,various economic indicators have shown a significant downward trend in recent years.Through the systematic analysis of the development... The food industry has developed into a leading industry in Northeast China.However,various economic indicators have shown a significant downward trend in recent years.Through the systematic analysis of the development trend of food industry in Northeast China in the past ten years,especially in 2014,it is found that in the context of stable and smooth operation of the food industry in China,the efficiency of the main processing industries declines in the three northeastern provinces of China,there is a simultaneous decline in the share of output value of the leading industries in the output value of manufacturing sector in three provinces,the collective and individual capital withdrawal is obvious in the paid-up capital,and there is a simultaneous decline in the industrial production and sales rate and the export delivery value.The food industry in Northeast China has plunged into the dilemma of development.Finally,this article puts forward some targeted recommendations from aspects of policy making,industrial agglomeration and enterprise cultivation. 展开更多
关键词 Food industry Agro-food processing industry Industrial production and sales rate Industrial agglomeration Northeast China
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On Numerical Modelling of Industrial Powder Compaction Processes for Large Deformation of Endochronic Plasticity at Finite Strains
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作者 A R Khoei A Bakhshiani M Mofid 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期95-96,共2页
Compaction processes are one the most important par ts of powder forming technology. The main applications are focused on pieces for a utomotive, aeronautic, electric and electronic industries. The main goals of the c... Compaction processes are one the most important par ts of powder forming technology. The main applications are focused on pieces for a utomotive, aeronautic, electric and electronic industries. The main goals of the compaction processes are to obtain a compact with the geometrical requirements, without cracks, and with a uniform distribution of density. Design of such proc esses consist, essentially, in determine the sequence and relative displacements of die and punches in order to achieve such goals. A.B. Khoei presented a gener al framework for the finite element simulation of powder forming processes based on the following aspects; a large displacement formulation, centred on a total and updated Lagrangian formulation; an adaptive finite element strategy based on error estimates and automatic remeshing techniques; a cap model based on a hard ening rule in modelling of the highly non-linear behaviour of material; and the use of an efficient contact algorithm in the context of an interface element fo rmulation. In these references, the non-linear behaviour of powder was adequately desc ribed by the cap plasticity model. However, it suffers from a serious deficiency when the stress-point reaches a yield surface. In the flow theory of plasticit y, the transition from an elastic state to an elasto-plastic state appears more or less abruptly. For powder material it is very difficult to define the locati on of yield surface, because there is no distinct transition from elastic to ela stic-plastic behaviour. Results of experimental test on some hard met al powder show that the plastic effects were begun immediately upon loading. In such mater ials the domain of the yield surface would collapse to a point, so making the di rection of plastic increment indeterminate, because all directions are normal to a point. Thus, the classical plasticity theory cannot deal with such materials and an advanced constitutive theory is necessary. In the present paper, the constitutive equations of powder materials will be discussed via an endochronic theory of plasticity. This theory provides a unifi ed point of view to describe the elastic-plastic behaviour of material since it places no requirement for a yield surface and a ’loading function’ to disting uish between loading an unloading. Endochronic theory of plasticity has been app lied to a number of metallic materials, concrete and sand, but to the knowledge of authors, no numerical scheme of the model has been applied to powder material . In the present paper, a new approach is developed based on an endochronic rate independent, density-dependent plasticity model for describing the isothermal deformation behavior of metal powder at low homologous temperature. Although the concept of yield surface has not been explicitly assumed in endochronic theory, it is shown that the cone-cap plasticity yield surface (Fig.1), which is the m ost commonly used plasticity models for describing the behavior of powder materi al can be easily derived as a special case of the proposed endochronic theory. Fig.1 Trace of cone-cap yield function on the meridian pl ane for different relative density As large deformation is observed in powder compaction process, a hypoelastic-pl astic formulation is developed in the context of finite deformation plasticity. Constitutive equations are stated in unrotated frame of reference that greatly s implifies endochronic constitutive relation in finite plasticity. Constitutive e quations of the endochronic theory and their numerical integration are establish ed and procedures for determining material parameters of the model are demonstra ted. Finally, the numerical schemes are examined for efficiency in the model ling of a tip shaped component, as shown in Fig.2. Fig.2 A shaped tip component. a) Geometry, boundary conditio n and finite element mesh; b) density distribution at final stage of 展开更多
关键词 In On Numerical Modelling of Industrial Powder Compaction processes for Large Deformation of Endochronic Plasticity at Finite Strains
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