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Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China
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作者 De-zhi Yan Ru-kai Zhu +8 位作者 Hao Shou Zhao-hui Xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min Xu 《China Geology》 CAS CSCD 2024年第3期505-516,共12页
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this... Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits. 展开更多
关键词 Hyperpycnal flow Sedimentary characteristics Depositional process Gravity flow deposit Hyperpycnite red mud pebble Gray mud pebble Oil and gas exploration engineering Luanping Basin
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Strategies for Improving the Effectiveness of Professional Practice for Full-Time Professional Master Degree Postgraduate in Mineral Processing Engineering 被引量:1
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作者 Jiushuai Deng Juan Hu +3 位作者 Zhiqiang Xu Weidong Wang Zhongyi Bai Tingting Hu 《Journal of Contemporary Educational Research》 2023年第1期27-32,共6页
In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,in... In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,including insufficient time for practice,low management level,inadequate implementation of the double-supervisor system,and poor results of professional practice,has reduced the effectiveness of professional practice.In view of the aforementioned problems and the characteristics of the discipline,this paper proposes several strategies for improving the effectiveness of professional practice for postgraduates in mineral processing engineering. 展开更多
关键词 Mineral processing engineering FULL-TIME Application-oriented Master’s degree Professional practice
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HV Process Model of Software Development
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作者 Hemant Kumar Vipin Saxena 《Journal of Software Engineering and Applications》 2024年第7期553-570,共18页
Software Development Life Cycle (SDLC) is one of the major ingredients for the development of efficient software systems within a time frame and low-cost involvement. From the literature, it is evident that there are ... Software Development Life Cycle (SDLC) is one of the major ingredients for the development of efficient software systems within a time frame and low-cost involvement. From the literature, it is evident that there are various kinds of process models that are used by the software industries for the development of small, medium and long-term software projects, but many of them do not cover risk management. It is quite obvious that the improper selection of the software development process model leads to failure of the software products as it is time bound activity. In the present work, a new software development process model is proposed which covers the risks at any stage of the development of the software product. The model is named a Hemant-Vipin (HV) process model and may be helpful for the software industries for development of the efficient software products and timely delivery at the end of the client. The efficiency of the HV process model is observed by considering various kinds of factors like requirement clarity, user feedback, change agility, predictability, risk identification, practical implementation, customer satisfaction, incremental development, use of ready-made components, quick design, resource organization and many more and found through a case study that the presented approach covers many of parameters in comparison of the existing process models. . 展开更多
关键词 Software process Model Software Development Software engineering Software Risk Management and Software Quality
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Formation,evolution,reconstruction of black shales and their influence on shale oil and gas resource
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作者 Shi-zhen Li Qiu-chen Xu +11 位作者 Mu Liu Guo-heng Liu Yi-fan Li Wen-yang Wang Xiao-guang Yang Wei-bin Liu Yan-fei An Peng Sun Tao Liu Jiang-hui Ding Qian-chao Li Chao-gang Fang 《China Geology》 CAS CSCD 2024年第3期551-585,共35页
Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential en... Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment. 展开更多
关键词 Black shales Shale oil and gas resource effects Sedimentary environment Sedimentary process Organic matter accumulation Diagenetic evolution thermal evolution Organic matter and inorganic minerals Tectonic reconstruction Oil and gas exploration engineering VEINS Fluid activity
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Review of Power Supply and Distribution Construction Technology for Highway Electromechanical Engineering
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作者 Li Liu 《Journal of Electronic Research and Application》 2024年第2期27-32,共6页
In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expan... In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expansion of highway construction,power supply,and distribution has led to several challenges in mechanical and electrical engineering technology.Ensuring the safe,stable,and cost-effective operation of the power supply and distribution system to meet the diverse requirements of highway operations has become a pressing issue.This article takes an example of a highway electromechanical engineering power supply and distribution construction project to provide insight into the construction process of highway electromechanical engineering power supply and distribution technology. 展开更多
关键词 HIGHWAY Mechanical and electrical engineering Power supply and distribution construction technology Construction process
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APPLICATION OF GREY SYSTEM THEORY TO PROCESSING OF MEASURING DATA IN REVERSE ENGINEERING 被引量:3
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作者 平雪良 周儒荣 安鲁陵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期36-41,共6页
The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured d... The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured data usually have some abnormalities. When the abnor mal data are eliminated by filtering, blanks are created. The grey generation an d GM(1,1) are used to create new data for these blanks. For the uneven data sequ en ce created by measuring error, the mean generation is used to smooth it and then the stepwise and smooth generations are used to improve the data sequence. 展开更多
关键词 reverse engineering gr ey system theory DIGITIZATION data processing grey generation
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Review on the study of metallurgical process engineering 被引量:11
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作者 Rui-yu Yin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1253-1263,共11页
After nearly one hundred years of research, metallurgy(metallurgical science and engineering) has gradually become a system with three levels of knowledge:(1) micro metallurgy at the atomic/molecular scale,(2) process... After nearly one hundred years of research, metallurgy(metallurgical science and engineering) has gradually become a system with three levels of knowledge:(1) micro metallurgy at the atomic/molecular scale,(2) process metallurgy at the procedure/device, and(3) macrodynamic metallurgy at the full process/process group. Macro-dynamic metallurgy development must eliminate the concept of an "isolated system" and establish concepts of "flow," "process network," and "operating program" to study the "structure–function–efficiency" in the macrodynamic operation of metallurgical manufacturing processes. It means considering "flow" as the ontology and observing dynamic change by"flow" to solve the green and intelligent potential of metallurgical enterprises. Metallurgical process engineering is integrated metallurgy, toplevel designed metallurgy, macro-dynamic operated metallurgy, and engineering science level metallurgy. Metallurgical process engineering is a cross-level, comprehensive, and integrated study of the macro-dynamic operation of manufacturing processes. Metallurgical process engineering studies the physical nature and constitutive characteristics of the dynamic operation of steel manufacturing process, as well as the analysis-optimization of the set of procedure functions, coordination-optimization of the set of procedures' relations, and reconstruction-optimization of the set of procedures in the manufacturing process. The study establishes rules for the macro operation of the manufacturing process, as well as dynamic and precise objectives of engineering design and production operation. 展开更多
关键词 metallurgical process engineering cross-level comprehensive integration macro-dynamic operation new branch of metallurgy
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Construction and Practices of the Course of Software Process&Tools Oriented Certified in Engineering Education 被引量:2
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作者 Guoxiang Fan Yong Guo +1 位作者 Zhiying Tu Zhongjie Wang 《计算机教育》 2021年第12期132-139,共8页
In recent years,it is the general trend to adopt the standards of international engineering education certification to construct curriculum.“Software Process and Tools”is one of the core courses of Harbin Institute ... In recent years,it is the general trend to adopt the standards of international engineering education certification to construct curriculum.“Software Process and Tools”is one of the core courses of Harbin Institute of Technology’s software engineering undergraduate training program.Focusing on the construction work and practical exploration of the course in the process of reforming the software engineering professional curriculum system,and how to achieve the standards of engineering education certification,This paper makes a review and summary.This paper focuses on the status and the role of the course in the whole curriculum system,as well as project-driven teaching content design and practical teaching methods.And summarizes the experience and results of 3 rounds of teaching practice. 展开更多
关键词 engineering education certification software engineering major software process and tools curriculum construction
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Evaluation of Environmental Sound Pressure Level,Drawing of Noise-Isosonic Map Using Surfer V.19,and Prioritization of Engineering Noise Control Methods Using the Analytic Hierarchy Process(AHP):A Field Study in CGS Stations
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作者 Sajad Zare Abdolrasoul Rahmani +3 位作者 Javad Korouzhdeh Masoud Hajghani Rouhollah Rostami Reza Esmaeili 《Sound & Vibration》 EI 2022年第3期275-291,共17页
Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and impl... Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and implement noise control plans in occupational environments is necessary.Thus,the present study aimed to review environmental sound measurements,drawing of noise maps,and prioritizing the engineering noise control methods using the Analytic Hierarchy Process(AHP).This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations(CGSs)of Kerman,Iran in 2021.The present study was done in two phases.In the first phase,six CGSs were investigated to measure and evaluate the noise.In addition,the noise map of a CGS was drawn using the Surfer software.Finally,the AHP was used in the second phase of the research to prioritize the control measures.In this phase,four criteria and ten alternatives were identified.According to first phase results,the sound pressure level(SPL)of the stations varied from 76 to 98 dBA.Besides,the majority of the studied stations had a sound level higher than 85 dBA(danger zone).The second phase of the study showed that out of the four evaluated criteria,the executability criterion had the highest impact and the cost criterion had the lowest impact on the selection of control measures with a weight of 0.587 and 0.052,respectively.Based on the results of prioritization of the alternatives,using a silenced regulator(weight of 0.223)and increasing the thickness of the tube(weight of 0.023)had the highest and lowest priorities among the alternatives,respectively.The use of engineering noise control methods such as using silenced regulators was the best way to control the noises of CGSs.Additionally;it is noteworthy that AHP is a practical method for prioritizing alternatives to achieve the most accurate decision-making.The results of AHP can be of great help to health and safety experts and managers in choosing the sound engineering control measures more precisely. 展开更多
关键词 engineering noise control sound pressure level noise map analytic hierarchy process
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The application of business process re-engineering in Chinese enterprises
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作者 刘全顺 刘利军 关小吉 《Journal of Coal Science & Engineering(China)》 2002年第2期107-112,共6页
After joining in WTO,Chinese enterprises face more intense competitive environments. The problems, such as many foreign capital enterprises swarming into China, increasing market competitive ability, keeping on nation... After joining in WTO,Chinese enterprises face more intense competitive environments. The problems, such as many foreign capital enterprises swarming into China, increasing market competitive ability, keeping on national and international market, have become more serious to enterprise’s decision maker. At the same time, the information technology is developing quickly, then business process re engineering will become valid path for enterprise increasing market competitive ability. As a case study, this paper applies Business Process Re engineering(BPR) approach to analyze a Chinese company. 展开更多
关键词 business process re engineering information technology market competitive ability
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Reinforcement Learning in Process Industries:Review and Perspective
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作者 Oguzhan Dogru Junyao Xie +6 位作者 Om Prakash Ranjith Chiplunkar Jansen Soesanto Hongtian Chen Kirubakaran Velswamy Fadi Ibrahim Biao Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期283-300,共18页
This survey paper provides a review and perspective on intermediate and advanced reinforcement learning(RL)techniques in process industries. It offers a holistic approach by covering all levels of the process control ... This survey paper provides a review and perspective on intermediate and advanced reinforcement learning(RL)techniques in process industries. It offers a holistic approach by covering all levels of the process control hierarchy. The survey paper presents a comprehensive overview of RL algorithms,including fundamental concepts like Markov decision processes and different approaches to RL, such as value-based, policy-based, and actor-critic methods, while also discussing the relationship between classical control and RL. It further reviews the wide-ranging applications of RL in process industries, such as soft sensors, low-level control, high-level control, distributed process control, fault detection and fault tolerant control, optimization,planning, scheduling, and supply chain. The survey paper discusses the limitations and advantages, trends and new applications, and opportunities and future prospects for RL in process industries. Moreover, it highlights the need for a holistic approach in complex systems due to the growing importance of digitalization in the process industries. 展开更多
关键词 process control process systems engineering reinforcement learning
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Time-frequency Feature Extraction Method of the Multi-Source Shock Signal Based on Improved VMD and Bilateral Adaptive Laplace Wavelet 被引量:2
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作者 Nanyang Zhao Jinjie Zhang +2 位作者 Zhiwei Mao Zhinong Jiang He Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第2期166-179,共14页
Vibration signals have the characteristics of multi-source strong shock coupling and strong noise interference owing to the complex structure of reciprocating machinery.Therefore,it is difficult to extract,analyze,and... Vibration signals have the characteristics of multi-source strong shock coupling and strong noise interference owing to the complex structure of reciprocating machinery.Therefore,it is difficult to extract,analyze,and diagnose mechanical fault features.To accurately extract sensitive features from the strong noise interference and unsteady monitoring signals of reciprocating machinery,a study on the time-frequency feature extraction method of multi-source shock signals is conducted.Combining the characteristics of reciprocating mechanical vibration signals,a targeted optimization method considering the variational modal decomposition(VMD)mode number and second penalty factor is proposed,which completed the adaptive decomposition of coupled signals.Aiming at the bilateral asymmetric attenuation characteristics of reciprocating mechanical shock signals,a new bilateral adaptive Laplace wavelet(BALW)is established.A search strategy for wavelet local parameters of multi-shock signals is proposed using the harmony search(HS)method.A multi-source shock simulation signal is established,and actual data on the valve fault are obtained through diesel engine fault experiments.The fault recognition rate of the intake and exhaust valve clearance is above 90%and the extraction accuracy of the shock start position is improved by 10°. 展开更多
关键词 Shock Signal processing WAVELET VMD Fault diagnosis Diesel engine
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Green microfluidics in microchemical engineering for carbon neutrality 被引量:2
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作者 Qingming Ma Jianhong Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期332-345,共14页
The concept of“carbon neutrality”poses a huge challenge for chemical engineering and brings great opportunities for boosting the development of novel technologies to realize carbon offsetting and reduce carbon emiss... The concept of“carbon neutrality”poses a huge challenge for chemical engineering and brings great opportunities for boosting the development of novel technologies to realize carbon offsetting and reduce carbon emissions.Developing high-efficient,low-cost,energy-efficient and eco-friendly microfluidicbased microchemical engineering is of great significance.Such kind of“green microfluidics”can reduce carbon emissions from the source of raw materials and facilitate controllable and intensified microchemical engineering processes,which represents the new power for the transformation and upgrading of chemical engineering industry.Here,a brief review of green microfluidics for achieving carbon neutral microchemical engineering is presented,with specific discussions about the characteristics and feasibility of applying green microfluidics in realizing carbon neutrality.Development of green microfluidic systems are categorized and reviewed,including the construction of microfluidic devices by bio-based substrate materials and by low carbon fabrication methods,and the use of more biocompatible and nondestructive fluidic systems such as aqueous two-phase systems(ATPSs).Moreover,low carbon applications benefit from green microfluidics are summarized,ranging from separation and purification of biomolecules,high-throughput screening of chemicals and drugs,rapid and cost-effective detections,to synthesis of fine chemicals and novel materials.Finally,challenges and perspectives for further advancing green microfluidics in microchemical engineering for carbon neutrality are proposed and discussed. 展开更多
关键词 Microchemical engineering Carbon neutrality MICRofLUIDICS Aqueous two-phase systems(ATPSs) ENVIRONMENT Chemical processes
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Research on Quality Management Measures of Green Building Construction
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作者 Jie Hong Xiang Xu 《Journal of Architectural Research and Development》 2024年第3期8-13,共6页
Urbanization has led to the rapid development of the construction industry.However,this has also led to higher requirements for the construction engineering management.Other than the quality monitoring of engineering ... Urbanization has led to the rapid development of the construction industry.However,this has also led to higher requirements for the construction engineering management.Other than the quality monitoring of engineering construction,the energy-saving properties of the building should also be considered.Therefore,a scientific management approach should be adopted to improve green building management.This paper primarily examines the importance of quality management in green building construction,along with the factors influencing it.It also identifies the quality issues present in current green building construction.Finally,it proposes measures for quality management in the green building construction process to facilitate the industry’s healthy development. 展开更多
关键词 Green building engineering Construction process control Quality management Construction publicity
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State of the Art Manufacturing and Engineering of Nanocellulose: A Review of Available Data and Industrial Applications 被引量:9
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作者 Serge Rebouillat Fernand Pla 《Journal of Biomaterials and Nanobiotechnology》 2013年第2期165-188,共24页
This review provides a critical overview of the recent methods and processes developed for the production of cellulose nanoparticles with controlled morphology, structure and properties, and also sums up (1) the proce... This review provides a critical overview of the recent methods and processes developed for the production of cellulose nanoparticles with controlled morphology, structure and properties, and also sums up (1) the processes for the chemical modifications of these particles in order to prevent their re-aggregation during spray-drying procedures and to increase their reactivity, (2) the recent processes involved in the production of nanostructured biomaterials and composites. The structural and physical properties of those nanocelluloses, combined with their biodegradability, make them materials of choice in the very promising area of nanotechnology, likely subject to major commercial successes in the context of green chemistry. With a prospective and pioneering approach to the subject matter, various laboratories involved in this domain have developed bio-products now almost suitable to industrial applications;although some important steps remain to be overcome, those are worth been reviewed and supplemented. At this stage, several pilot units and demonstration plants have been built to improve, optimize and scale-up the processes developed at laboratory scale. Industrial reactors with suitable environment and modern control equipment are to be expected within that context. This review shall bring the suitable processing dimension that may be needed now, given the numerous reviews outlining the product potential attributes. An abundant literature database, close to 250 publications and patents, is provided, consolidating the various research and more practical angles. 展开更多
关键词 NANOCELLULOSE processes Production Modifications BIOCOMPOSITES BIOMATERIALS engineering reNEWABLE Bioadditives FIBROUS Nanostructures Green Chemistry
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Industrial application prospects and key issues of the pure-hydrogen reduction process 被引量:6
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作者 Lei Wang Peimin Guo +1 位作者 Lingbing Kong Pei Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第10期1922-1931,共10页
The industrial application prospect and key issues in basic theory and application are discussed by the methods of theoretical analysis and calculation to promote the development of the pure-hydrogen reduction process... The industrial application prospect and key issues in basic theory and application are discussed by the methods of theoretical analysis and calculation to promote the development of the pure-hydrogen reduction process.According to the discussion of thermodynamics and kinetics of pure-hydrogen reduction reaction,the reduction reaction of iron oxide by pure hydrogen is an endothermic reaction,and the reaction rate of hydrogen reduction is significantly faster than that of carbon reduction.To explore the feasibility of the industrial applications of pure-hydrogen reduction,we design the hydrogen reduction reactor and process with reference to the industrialized hydrogen-rich reduction process and put forward the methods of appropriately increasing the reduction temperature,pressure,and temperature of iron ore into the furnace to accelerate the reaction rate and promote the reduction of iron oxide.The key technical parameters in engineering applications,such as hydrogen consumption,circulating gas volume,and heat balance,are discussed by theoretical calculations,and the optimized parameter values are proposed.The process parameters,cost,advantages,and disadvantages of various current hydrogen production methods are compared,and the results show that hydrogen production by natural gas reforming has a good development prospect.Through the discussion of the corrosion mechanism of high-temperature and high-pressure hydrogen on heat-resistant steel materials and the corrosion mechanism of H_2S in the hydrogen gas on steel,the technical ideas of developing new metal temperature-resistant materials,metal coating materials,and controlling gas composition are put forward to provide guidance for the selection of heater and reactor materials.Finally,the key factors affecting the smooth operation of the hydrogen reduction process in engineering applications are analyzed,offering a reference for the industrial application of the purehydrogen reduction process. 展开更多
关键词 pure hydrogen reduction process design engineering application reactor material sulfur and nitrogen balance
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In-situ experiment investigations of hydrothermal process of highway in deep seasonal frozen soil regions of Inner Mongolia, China 被引量:5
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作者 ZHANG Hong-wei WANG Xue-ying +1 位作者 ZHAO Xin LIU Peng-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第7期2082-2093,共12页
To reveal the influencing factors and changing rules for the hydrothermal interaction process of highway subgrade, the field measurements of Shiwei-Labudalin Highway in Inner Mongolia, China was conducted for 3 years,... To reveal the influencing factors and changing rules for the hydrothermal interaction process of highway subgrade, the field measurements of Shiwei-Labudalin Highway in Inner Mongolia, China was conducted for 3 years, based on which the freezing-thawing rules and water content changing characteristics were analyzed. The main results show the subgrade presents a frequent freezing-thawing alternation, and the water content of subgrade exhibits an obvious seasonal alternation. The subbase has the maximum water content, while the base has the minimum water content. The change of water flux is concentrated in the thawing period and consistent with the change of temperature gradient. The subbase layer has the most active water flux due to the heat absorption and impermeability of pavement that easily causes the water accumulation in this layer. Therefore, the prevention and treatment for the freezing-thawing disease should be started from heat insulation and water resistance. 展开更多
关键词 subgrade engineering hydrothermal process field observation seasonal frozen soil regions freezing-thawing disease
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Geometrical Reconstruction and CNC Process of Spurious Tympanic Membrane Based on Reverse Engineering 被引量:1
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作者 LU Hong~1 PENG Jun~1 ZHOU Yongqing~2 1.School of Mechanical and Electrical Engineering,Wuhan University of Technology,Wuhan 430070,China 2.Bethune International Peace Hospital of PLA,Shijiazhuang 050082,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期592-595,共4页
Perforation of tympanic membrane is one of the main reasons for both deafness and dyssaudia.We could improve and restore audition by restoring or replacing the tympanic membrane.So,whether you can make the spurious ty... Perforation of tympanic membrane is one of the main reasons for both deafness and dyssaudia.We could improve and restore audition by restoring or replacing the tympanic membrane.So,whether you can make the spurious tympanic membrane successfully is one of the keys to a successful operation.Utilizing CMM (Coordinate Measuring Machine) measurement equipment, we measured tympanic membrane model precisely and digitally.We also analysed the measured data by point to surface and we have successfully reconstructed the CAD model of the spurious tympanic membrane.Using the model we have got,we schemed out the mold of spurious tympanic membrane.In addition,we utilized MasterCAM compiling CNC (Computerized Numerical Con- trol) code and simulating the course of working.Ultimately,we obtained the mold of spurious tympanic membrane.Our research in this article has great significance to the success of spurious tympanic membrane grafting operation. 展开更多
关键词 reVERSE engineering SPURIOUS tympanic membrane GEOMETRICAL reCONSTRUCTION CNC process
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Development of Optimal Maintenance Policies for Offshore Wind Turbine Gearboxes Based on the Non-homogeneous Continuous-Time Markov Process 被引量:1
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作者 Mingxin Li Jichuan Kang +1 位作者 Liping Sun Mian Wang 《Journal of Marine Science and Application》 CSCD 2019年第1期93-98,共6页
Gearbox in offshore wind turbines is a component with the highest failure rates during operation. Analysis of gearbox repair policy that includes economic considerations is important for the effective operation of off... Gearbox in offshore wind turbines is a component with the highest failure rates during operation. Analysis of gearbox repair policy that includes economic considerations is important for the effective operation of offshore wind farms. From their initial perfect working states, gearboxes degrade with time, which leads to decreased working efficiency. Thus, offshore wind turbine gearboxes can be considered to be multi-state systems with the various levels of productivity for different working states. To efficiently compute the time-dependent distribution of this multi-state system and analyze its reliability, application of the nonhomogeneous continuous-time Markov process(NHCTMP) is appropriate for this type of object. To determine the relationship between operation time and maintenance cost, many factors must be taken into account, including maintenance processes and vessel requirements. Finally, an optimal repair policy can be formulated based on this relationship. 展开更多
关键词 Maintenance policy NON-HOMOGENEOUS CONTINUOUS-TIME MARKOV process ofFSHOre wind TURBINE gearboxes reliability analysis Failure rates System engineering
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Data-driven optimal operation of the industrial methanol to olefin process based on relevance vector machine 被引量:2
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作者 Zhiquan Wang Liang Wang +1 位作者 Zhihong Yuan Bingzhen Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期106-115,共10页
Methanol to olefin(MTO)technology provides the opportunity to produce olefins from nonpetroleum sources such as coal,biomass and natural gas.More than 20 commercial MTO plants have been put into operation.Till now,con... Methanol to olefin(MTO)technology provides the opportunity to produce olefins from nonpetroleum sources such as coal,biomass and natural gas.More than 20 commercial MTO plants have been put into operation.Till now,contributions on optimal operation of industrial MTO plants from a process systems engineering perspective are rare.Based on relevance vector machine(RVM),a data-driven framework for optimal operation of the industrial MTO process is established to fully utilize the plentiful industrial data sets.RVM correlates the yield distribution prediction of main products and the operation conditions.These correlations then serve as the constraints for the multi-objective optimization model to pursue the optimal operation of the plant.Nondominated sorting genetic algorithmⅡis used to solve the optimization problem.Comprehensive tests demonstrate that the ethylene yield is effectively improved based on the proposed framework.Since RVM does provide the distribution prediction instead of point estimation,the established model is expected to provide guidance for actual production operations under uncertainty. 展开更多
关键词 Methanol to olefins relevance vector machine Genetic algorithm Operation optimization Systems engineering process systems
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