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Curriculum Reform of Higher Vocational Mathematics Under the Background of Digital Transformation
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作者 Tianci Zhao 《Journal of Contemporary Educational Research》 2024年第4期215-220,共6页
Under the background of digital transformation,the reform of the higher vocational mathematics curriculum faces urgent challenges and opportunities.This article explores the impact of digital transformation on the ref... Under the background of digital transformation,the reform of the higher vocational mathematics curriculum faces urgent challenges and opportunities.This article explores the impact of digital transformation on the reform of higher vocational mathematics curriculum and emphasizes the importance of improving teaching methods centered on learners.The article proposes specific reform methods and discusses the practical application of digital technology in the reform process.By combining digital technology with specific reform methods,further conducting innovative practice research,and continuously exploring the path of reform,we can effectively improve the quality of higher vocational mathematics classroom teaching and provide strong support for the cultivation of comprehensive qualities and employment abilities. 展开更多
关键词 Digital transformation LEARNER-CENTERED Higher vocational mathematics Personalized development
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Age and genesis of the Danxia landform on Jianglang Mountain, Zhejiang Province 被引量:5
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作者 朱诚 彭华 +15 位作者 李中轩 张广胜 李兰 俞锦标 朱光耀 欧阳杰 钟宜顺 朱青 周书勤 郑朝贵 周日良 李东 朱雨鸣 吕文 武弘麟 徐龙生 《Journal of Geographical Sciences》 SCIE CSCD 2009年第5期615-630,共16页
Jianglang Mountain is situated at the transitional zone of South China fold-system, Jiangshan-Shaoxing deep fracture zone and Baoan-Xiakou-Zhangcun fracture zone. The forming of the Xiakou basin was attributed to the ... Jianglang Mountain is situated at the transitional zone of South China fold-system, Jiangshan-Shaoxing deep fracture zone and Baoan-Xiakou-Zhangcun fracture zone. The forming of the Xiakou basin was attributed to the pull-apart fault depression by the above fractures in earlier Cretaceous, afterward, series deposits such as Guantou formation (K1g), Chaochuan formation (K1c) and Fangyan formation (K1f) which belong to Yongkang group, the lower Cretaceous layer accumulated in the Xiakou basin. In late Cretaceous, the above fractures occurred to extrude and the basin began to uplift, meanwhile, amounts of tension fissures and joints were produced since Cenozoic, which accelerated water-dicing into bed-rock. Consequently, landform-building processing: weathering, eroding and collapsing etc. were prevalent as finally to develop the so-called Danxia landform. The Jianglang Mountain landscape zone of the Danxia landform to apply for world natural relics are relying on unique and unparalleled peak, sky-split valley with vivid stones and reviving of platform. What is more, there is significance of study at lithology, stratigraphy and paleo-biology. According to dating for specimen of ophitic vein through-crossing the Yongkang group of Yafeng Peak by K-Ar method, this article revealed the uplift age of red-bed basin to be 77.89±2.6 MaBP (K2) i.e. late Cretaceous, and it is the first chronological datum of Danxia landform research in China. 展开更多
关键词 ZHEJIANG Jianglang Mountain Danxia landform landform development landform genesis
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On Software Application Database Constraint-driven Design and Development
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作者 Christian Mancas Cristina Serban Diana Christina Mancas 《Journal of Computer Science Research》 2023年第1期31-45,共15页
This paper presents a methodology driven by database constraints for designing and developing(database)software applications.Much needed and with excellent results,this paradigm guarantees the highest possible quality... This paper presents a methodology driven by database constraints for designing and developing(database)software applications.Much needed and with excellent results,this paradigm guarantees the highest possible quality of the managed data.The proposed methodology is illustrated with an easy to understand,yet complex medium-sized genealogy software application driven by more than 200 database constraints,which fully meets such expectations. 展开更多
关键词 Database constraint-driven design and development Database constraint Data plausibility Software architecture Design and development the(elementary)mathematical data model MatBase
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Origin,discovery,exploration and development status and prospect of global natural hydrogen under the background of“carbon neutrality” 被引量:6
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作者 Qian-ning Tian Shu-qing Yao +2 位作者 Ming-juan Shao Wei Zhang Hai-hua Wang 《China Geology》 CAS 2022年第4期722-733,共12页
Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by 2050.Hydrogen is ... Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by 2050.Hydrogen is considered to be the most potential clean energy in this century under the background of carbon neutrality.At present,the industrial methods for producing hydrogen are mainly by steam-hydrocarbon(such as coal and natural gas)reforming and by electrolysis of water,while the exploration and development of natural hydrogen had just started.According to this literature review:(1)Natural hydrogen can be divided into three categories,including free hydrogen,hydrogen in inclusions and dissolved hydrogen;(2)natural hydrogen could be mainly from abiotic origins such as by deep-seated hydrogen generation,water-rock reaction or water radiolysis;(3)natural hydrogen is widely distributed and presents great potential,and the potential natural hydrogen sources excluding deep source of hydrogen is about(254±91)×10^(9) m^(3)/a according to a latest estimate;(4)at present,natural hydrogen has been mined in Mali,and the exploration and development of natural hydrogen has also been carried out in Australia,Brazil,the United States and some European countries,to find many favorable areas and test some technical methods for natural hydrogen exploration.Natural hydrogen is expected to be an important part of hydrogen energy production in the future energy pattern.Based on a thorough literature review,this study introduced the origin,classification,and global discovery of natural hydrogen,as well as summarized the current global status and discussed the possibility of natural hydrogen exploration and development,aiming to provide reference for the future natural hydrogen exploration and development. 展开更多
关键词 Carbon neutrality Energy transition New energy Hydrogen energy Natural hydrogen OCCURRENCE genesis RESOURCES Exploration and development Potential
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Design a New Model to Evaluate the Ecological Potential Land for Urban Development and Service (City of Zanjan)
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作者 Roghayeh Parchianloo Raziyeh Rahimi +2 位作者 Maryam Kiani Sadr Abdol Reza Karbasi Alireza Gharagozlo 《Open Journal of Ecology》 2017年第9期581-590,共10页
This study aimed to design a new ecological model to be used in ecological land evaluation studies, using careful planning and sustainable resource in the region to develop a sustainable and comprehensive guide. The r... This study aimed to design a new ecological model to be used in ecological land evaluation studies, using careful planning and sustainable resource in the region to develop a sustainable and comprehensive guide. The results show that the study area has grade 1 and 2 urban sustainable planning. Capability Grade 1 has area 149,724.25 hectares equal 22.2% that is stretched from East to West Range. Capability Grade2 has area about 18533.28 hectares equal 2.7% that located in the South, East and South-East. The results show that the greater extent of this range is the unsustainable site, which extends over 506,664.81 hectares, equivalent to 75.1% that areas compliance by the Environmental Protection area. Another important result of this study is unsuitable area for urban development and the range of services already seating workshops and industrial units. This is due to the arrival of adverse environmental effects. Therefore, this study has been focusing on reform of the status of land of use and the optimal use of the ecological potential. 展开更多
关键词 ECOLOGICAL CAPABILITY Assessment URBAN development GEOGRAPHIC Information System Linear MAtheMATICAL Model
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ACCELERATING THE DEVELOPMENT OF MATHEMATICAL AND PHYSICAL SCIENCES 被引量:3
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作者 CAS Division of Mathematics and Physics 《Bulletin of the Chinese Academy of Sciences》 1998年第2期121-125,共5页
This article discusses the important role of mathematical and physical sciences in, and their influence on, the development of natural science and modern technology, as well as social science and the humanities. On th... This article discusses the important role of mathematical and physical sciences in, and their influence on, the development of natural science and modern technology, as well as social science and the humanities. On the basis of the present situation in China, it calls for accelerating the development of the mathematical and physical sciences. 展开更多
关键词 ACCELERATING the development of MAtheMATICAL and PHYSICAL SCIENCES
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Genesis and Development of Porosity in Carbonate Reservoirs─Fluid Inclusion Evidence
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作者 覃建雄 曾允孚 《Chinese Journal Of Geochemistry》 EI CAS 1996年第4期364-373,共10页
Fluid inclusions in minerals filled in pores of reservoir rocks can be used as a good indicator of pore genesis and development so as to shed light on oil generation, migration and accumulation. The relationship betwe... Fluid inclusions in minerals filled in pores of reservoir rocks can be used as a good indicator of pore genesis and development so as to shed light on oil generation, migration and accumulation. The relationship between pore evolution and oil generation has been established based on fluid inclusion studies on the Lower Ordovician carbonate reservoir strata in the Ordos Basin, Northwest China. Seven stages of porosity developrnent can be recognized, i. e., the penecontemporaneous, the early and middle-late diagenetic, the supergene, the early, middle and late re-burying stages. The dissolution pores and fissures formed in the supergene and middle-late reburying stages and the strtJctural fractures formed in the late re-burying stage constitute the major traps of oil and gas. The major phase of oil migration and accumulation took place between Late Jurassic and Cretaceous, corresponding to the middle and late re-burying stages. The generation and accumulation of oil can be closely-related to Yenshanian tectonics. 展开更多
关键词 流体包裹体 碳酸盐 多孔性 地球化学 沉积物
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Development of Mathematical Model on Preparation of Functionally Graded Material by Co-sedimentation 被引量:6
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作者 Zhongmin YANG, Lianmeng ZHANG and Qiang SHEN Institute of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第2期275-277,共3页
From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and... From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation. 展开更多
关键词 CO MO development of Mathematical Model on Preparation of Functionally Graded Material by Co-sedimentation
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Rapid Prototype Development Approach for Genetic Programming
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作者 Pei He Lei Zhang 《Journal of Computer and Communications》 2024年第2期67-79,共13页
Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of ... Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of genetic operators, evolutionary controls and implementations of heuristic strategy, evaluations and other mechanisms. When designing genetic operators, it is necessary to consider the possible limitations of encoding methods of individuals. And when selecting evolutionary control strategies, it is also necessary to balance search efficiency and diversity based on representation characteristics as well as the problem itself. More importantly, all of these matters, among others, have to be implemented through tedious coding work. Therefore, GP development is both complex and time-consuming. To overcome some of these difficulties that hinder the enhancement of GP development efficiency, we explore the feasibility of mutual assistance among GP variants, and then propose a rapid GP prototyping development method based on πGrammatical Evolution (πGE). It is demonstrated through regression analysis experiments that not only is this method beneficial for the GP developers to get rid of some tedious implementations, but also enables them to concentrate on the essence of the referred problem, such as individual representation, decoding means and evaluation. Additionally, it provides new insights into the roles of individual delineations in phenotypes and semantic research of individuals. 展开更多
关键词 Genetic Programming Grammatical Evolution Gene Expression Programming Regression Analysis Mathematical Modeling Rapid Prototype development
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Predictive Mathematical and Statistical Modeling of the Dynamic Poverty Problem in Burundi: Case of an Innovative Economic Optimization System
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作者 Fulgence Nahayo Ancille Bagorizamba +1 位作者 Marc Bigirimana Irene Irakoze 《Open Journal of Optimization》 2021年第4期101-125,共25页
The mathematical and statistical modeling of the problem of poverty is a major challenge given Burundi’s economic development. Innovative economic optimization systems are widely needed to face the problem of the dyn... The mathematical and statistical modeling of the problem of poverty is a major challenge given Burundi’s economic development. Innovative economic optimization systems are widely needed to face the problem of the dynamic of the poverty in Burundi. The Burundian economy shows an inflation rate of -1.5% in 2018 for the Gross Domestic Product growth real rate of 2.8% in 2016. In this research, the aim is to find a model that contributes to solving the problem of poverty in Burundi. The results of this research fill the knowledge gap in the modeling and optimization of the Burundian economic system. The aim of this model is to solve an optimization problem combining the variables of production, consumption, budget, human resources and available raw materials. Scientific modeling and optimal solving of the poverty problem show the tools for measuring poverty rate and determining various countries’ poverty levels when considering advanced knowledge. In addition, investigating the aspects of poverty will properly orient development aid to developing countries and thus, achieve their objectives of growth and the fight against poverty. This paper provides a new and innovative framework for global scientific research regarding the multiple facets of this problem. An estimate of the poverty rate allows good progress with the theory and optimization methods in measuring the poverty rate and achieving sustainable development goals. By comparing the annual food production and the required annual consumption, there is an imbalance between different types of food. Proteins, minerals and vitamins produced in Burundi are sufficient when considering their consumption as required by the entire Burundian population. This positive contribution for the latter comes from the fact that some cows, goats, fishes, ···, slaughtered in Burundi come from neighboring countries. Real production remains in deficit. The lipids, acids, calcium, fibers and carbohydrates produced in Burundi are insufficient for consumption. This negative contribution proves a Burundian food deficit. It is a decision-making indicator for the design and updating of agricultural policy and implementation programs as well as projects. Investment and economic growth are only possible when food security is mastered. The capital allocated to food investment must be revised upwards. Demographic control is also a relevant indicator to push forward Burundi among the emerging countries in 2040. Meanwhile, better understanding of the determinants of poverty by taking cultural and organizational aspects into account guides managers for poverty reduction projects and programs. 展开更多
关键词 Poverty Problem Mathematical Modeling Applied Statistics Operational Research Symplectic Partitioned Runge Kutta Algorithm Dynamic Programming Matlab and Simulink AMPL KNITRO Gurobi Economic Optimization Technology Transfer Incubation of Results Sustainable development Goals
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Urban water system theory and its model development and application 被引量:1
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作者 Jun XIA Yongyong ZHANG +7 位作者 Dunxian SHE Shiyan ZHANG Jun YANG Mingquan LV Xiang ZHANG Anqi LUO Shengjun WU Yang LIU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第3期704-724,共21页
The urban water system theory is an extension of the basin water system science on an urban scale, providing a new systematic solution for the unbalanced human-water relationship and severe water challenges, such as w... The urban water system theory is an extension of the basin water system science on an urban scale, providing a new systematic solution for the unbalanced human-water relationship and severe water challenges, such as waterlogging, black and odorous water, and ecological degradation caused by urbanization. Most existing studies on urban water systems have focused on individual water cycle processes linked with water supply and sewage treatment plants, but mutual feedback between the water cycle and its associated material circulation and water ecology, as well as human processes, still needs further exploration. In this paper, the concept, theory, and technical methodology of the urban water system were developed based on the water cycle and basin water system science. The Urban Water System 5.0(UWS 5.0) model was developed by integrating the Time Variant Gain rainfall-runoff Model with Urban water system(TVGM_Urban) in different underlying surface conditions for analyzing the natural-social water cycle processes and their associated water environmental and ecological processes and the influence of multiscale sponge measures. Herein, five major simulation functions were realized: rainfall-runoff-nonpoint source pollutant load,water and pollutant transportations through the drainage network system, terminal regulation and purification, socioeconomic water cycle, and water system assessment and regulation. The location for the case study used in this paper was Wuhan City. The findings showed that the entire urban water system should consider the built-up area and its associated rivers and lakes as the research object and explore the integrations among the urban natural-social water cycle and river regulations inside and outside of the city as well as the effects of socioeconomic development and sponge measures on the water quantity-quality-ecology processes. The UWS 5.0 model efficiently simulated the urban rainfall-runoff process, total nitrogen(TN) and total phosphorus(TP) concentrations in water bodies, and characteristic indicators of socioeconomic development. For the rainfall-runoff simulations, the correlation coefficient and Nash-Sutcliffe efficiency(NSE) fall under the excellent and good classes, respectively. For the TN and TP concentration simulations, results exhibited good bias and the correlation coefficients exceeded 0.90 for 78.1% of the sampled sites. The simulation of 18 socioeconomic indicators provided excellent bias, correlation coefficient, and NSE values of 100%, 83.3%, and 69.4% to total indicators, respectively. Based on the well-calibrated UWS 5.0 model, the source sponge,artificial enhancement, and source reduction-path interception-terminal treatment measures were optimized, which considerably mitigated waterlogging, black and odorous water, and lake eutrophication, respectively. The mitigation performance revealed that the maximum inundated area for a once-in-10-year rainfall event was reduced by 32.6%, the removal ratio of the black and odorous water area was 65%, the comprehensive trophic state index of water bodies was reduced by 37%, and the green development level of Wuhan City in 2020 increased from 0.56 to 0.67. This study is expected to advance the intersection and development of multidisciplinary fields(e.g., urban hydrology, environmental science, and ecology) and offer an important theoretical and technical basis for solving urban complex water issues and promoting green development of cities. 展开更多
关键词 Urban water system Human-water relationship Water issue Green development theoretical basis Mathematical model
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Effect of Development of Caofeidian Harbor Area in Bohai Bay on Hydrodynamic Sediment Environment 被引量:8
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作者 陆永军 左利钦 +2 位作者 季荣耀 徐啸 黄建维 《China Ocean Engineering》 SCIE EI 2008年第1期97-112,共16页
Based on the characteristics of waves, tidal currents, sediment and seabed evolution in the Caofeidian sea area in the Bohai Bay, a 2D sediment mathematical model of waves and tidal currents is employed to study the d... Based on the characteristics of waves, tidal currents, sediment and seabed evolution in the Caofeidian sea area in the Bohai Bay, a 2D sediment mathematical model of waves and tidal currents is employed to study the development schemes of the harbor. Verification of spring and neap tidal currents and sediment in the winter and summer of 2006 shows that the calculated values of tidal stages as well as flow velocities, flow directions and sediment concentration of 15 synchronous vertical lines are in good agreement with the measured data. Also, deposition and erosion of the sea area in front of Caofeidian ore terminal induced by suspended load under tidal currents and waves are verified; it shows that the calculated values of depth of deposition and erosion as well as their distribution are close to the measured data. Furthermore, effects of reclamation scheme of island in front of the land behind Caofeidian harbor on the hydrodynamic environment are studied, including changes of flow velocities in the deep channels at the south side of Caofeidian foreland and Laolonggou and in various harbor basins, as well as changes of deposition and erosion of seabed induced by the project. 展开更多
关键词 WAVE tidal current SEDIMENT mathematical model development of harbor area Caofeidian
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COMPARISON OF THE STRUCTURAL CHARACTERISTICS OF DEVELOPED VERSUS UNDEVELOPED MID-LEVEL VORTEXES 被引量:1
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作者 黄辉军 袁金南 +1 位作者 李春晖 毛伟康 《Journal of Tropical Meteorology》 SCIE 2014年第1期57-65,共9页
Using the NCEP 1°×1°reanalysis data,several obvious differences of the structural characteristics of developed versus undeveloped mid-level vortexes are studied.First,the central vorticity of the develo... Using the NCEP 1°×1°reanalysis data,several obvious differences of the structural characteristics of developed versus undeveloped mid-level vortexes are studied.First,the central vorticity of the developed mid-level vortex increases towards higher levels while the undeveloped one decreases.The low-level convergence structure maintains well in the developed mid-level vortex whereas the undeveloped one does badly.Second,on the one hand,according to the symmetric analysis,the horizontal wind field and wind vertical section of the developed mid-level vortex are well symmetric while those of the undeveloped one are less symmetric.Meanwhile,weak wind vertical shear help the developed mid-level vortex to establish a warm core in upper-and mid-levels of the troposphere.On the other hand,according to the balance analysis,better balance between wind and pressure is shown in the mid-and lower-levels of the troposphere of the developed mid-level vortex than in those of the undeveloped vortex.Third,positive anomaly of potential vorticity is enhanced and developed in the vertical direction of the developed vortex.However,the undeveloped vortex weakens with a weak positive anomaly. 展开更多
关键词 South China Sea area tropical cyclone genesis and development mid-level vortex structural characteristics
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Does the McNeill Alexander model accurately predict maximum walking speed in novice and experienced race walkers?
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作者 Andrew J.Harrison Patrick G.Molloy Laura-Anne M.Furlong 《Journal of Sport and Health Science》 SCIE 2018年第3期372-377,共6页
Background:Mathematical models propose leg length as a limiting factor in determining the maximum walking velocity.This study evaluated the effectiveness of a leg length-based model in predicting maximum walking veloc... Background:Mathematical models propose leg length as a limiting factor in determining the maximum walking velocity.This study evaluated the effectiveness of a leg length-based model in predicting maximum walking velocity in an applied race walking situation,by comparing experienced and novice race walkers during conditions where strictly no flight time(FT)was permitted and in simulated competition conditions(i.e.,FT<40 ms).Methods:Thirty-four participants(18 experienced and l6 novice race walkers)were recruited for this investigation.An Optojump Next system(8 m)was used to determine walking velocity,step frequency,step length,ground contact time,and FT during race walking over a range of velocities.Comparisons were made between novice and experienced participants in predicted maximum velocity and actual velocities achieved with no flight and velocities with FT<40 ms.The technical effectiveness of the participants was assessed using the ratio of maximum velocity to predicted velocity.Results:In novices,no significant difference was found between predicted and maximum walking speeds without FT but there was a small 5.8%gain in maximum speed when FT≤40 ms.In experienced race walkers,there was a significant reduction in maximum walking speed compared with predicted maximum(p<0.01)and a 11.7%gain in maximum walking speed with FT<40 ms.Conclusion:Leg length was a good predictor of maximal walking velocity in novice walkers but not a good predictor of maximum walking speed in well-trained walkers who appear to have optimised their walking technique to make use of non-visible flight periods of less than 40 ms.The gain in velocity above predicted maximum may be a useful index of race walking proficiency. 展开更多
关键词 BIOMECHANICS GAIT Mathematical modelling RACE walking Sports TECHNIQUE TECHNIQUE development
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Mathematical Model of the Geothermal Water Resources in the South Hot Spring System in Chongqing
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作者 Liu Dongyan Luo Yunju Liu Xinrong 《Journal of China University of Geosciences》 SCIE CSCD 2005年第3期262-267,共6页
The geothermal waters of south hot spring, small hot spring and Qiaokouba in Chongqing, are all part of the south hot spring geothermal water system. Exploitation has caused a decline in the water levels of the south ... The geothermal waters of south hot spring, small hot spring and Qiaokouba in Chongqing, are all part of the south hot spring geothermal water system. Exploitation has caused a decline in the water levels of the south and small hot springs, which have not flowed naturally for 15 years. Now, bores pump geothermal water to the springs. If the water level drops below the elevation of the rivers, river-water will replenish the geothermal water, destroying this resource. It is therefore an urgent task to model the geothermal water system, to enable sustainable development and continued use of the geothermal water in Qiaokouba. A numerical simulation of the geothermal water system was adopted and a quantitative study on the planning scheme was carried out. A mathematical model was set up to simulate the whole geothermal water system, based on data from the research sites. The model determined the maximum sustainable water yield in Qiaokouba and the two hot springs, and the south hot spring and small hot spring sustainable yields are 1 100 m^3/d and 700 m^3/d from 2006 to 2010, 1 300 m^3/d and 1 000 m^3/d from 2011 to 2015, and 1 500 m^3/d and 1 200 m^3/d from 2016 to 2036. The maximum exploitable yield is 3 300 m^3/d from 2006 to 2036 in Qiaokouba. The model supplies a basis to adequately exploit and effectively protect the geothermal water resources, and to continue to develop the geothermal water as a tourist attraction in Chongqing. 展开更多
关键词 south hot spring geothermal water system geothermal water resources mathematical model sustainable development YIELD
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新疆煤层气大规模高效勘探开发关键技术领域研究进展与突破方向 被引量:5
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作者 桑树勋 李瑞明 +10 位作者 刘世奇 周效志 韦波 韩思杰 郑司建 皇凡生 刘统 王月江 杨曙光 秦大鹏 周梓欣 《煤炭学报》 EI CAS CSCD 北大核心 2024年第1期563-585,共23页
新疆煤层气资源量7.5万亿m^(3)(2000 m以浅),已施工煤层气井450口,年产气量达到0.8亿m^(3),新疆维吾尔自治区提出了2025年实现煤层气产量25亿m^(3)的目标,煤层气大规模高效开发成为紧迫的重大需求。从煤层气富集模式与选区技术、“甜点... 新疆煤层气资源量7.5万亿m^(3)(2000 m以浅),已施工煤层气井450口,年产气量达到0.8亿m^(3),新疆维吾尔自治区提出了2025年实现煤层气产量25亿m^(3)的目标,煤层气大规模高效开发成为紧迫的重大需求。从煤层气富集模式与选区技术、“甜点”预测探测技术、加速滚动开发与快速增储上产策略、地质适配性开发技术、煤层气与煤炭、油气协同开发技术5个关键技术领域,系统梳理了新疆煤层气勘探开发已取得的主要研究进展,分析提出了可能突破方向。研究表明:新疆煤储层具有多-厚煤层普遍、低阶煤发育、急倾斜煤层多见、煤体变形与构造控制显著、水文条件和露头条件复杂,和三“低”(含气量低、甲烷体积分数低、含气饱和度低)五“高”(高含气强度、高孔隙度、高地应力变化、高储层压力变化、高渗透率变化)的含气性及物性等煤层气地质独特性;煤层气成因与富集模式具有多样性,包括生物成因气、热成因气或生物-热复合成因及其相应富集模式,生物成因气藏或生物成因气贡献普遍;煤层气分布赋存规律呈现前陆盆地、山间盆地显著差异性;创新形成基于“两”分开(浅部与深部,低阶煤与中高阶煤)“两”结合(地质评价与工程评价,多元数据)的科学评价与基于“机器学习+三维地质建模”的精准选区技术是第1个突破方向。深部煤层气/煤系气“甜点”发育区域主要为盆内坳陷的凸起、盆内隆起的凹陷、盆缘斜坡,高产井位多为构造高点,发育层位为割理裂隙发育的原生结构煤层或孔裂隙发育的煤系砂砾岩储层;基于“地球物理+岩石物理+岩石力学地层新方法”和“地质甜点+工程甜点新理念”的深部煤层气/煤系气“甜点”预测探测技术是第2个突破方向。低风险、短周期、高效率、多批次工程部署是加速滚动开发的基本原则;中浅部煤层气快速增储上产技术策略是在优选新区块布井建井、对老区块煤层气井进行增产改造;深部煤层气快速增储上产技术策略是在大型盆地缓坡深部和盆内凸起“甜点”区优先部署开发;科学加速滚动开发与高效快速增储上产的工程部署方法与技术策略是第3个突破方向。在井网井型差异性优化部署、低储层伤害钻井固井、高可靠性录井测井试井、多井型高效分段压裂、低套压-控压排采管控等工程技术取得重要进展;发展构建新疆煤层气大规模高效勘探开发地质适配性技术体系是第4个突破方向。开展先采气后采煤、煤层气与煤共采、煤层气与原位富油煤共采,推动中浅部煤层气与煤炭协同勘探开发;开展煤系叠合型气藏开发、煤层气与煤系气共探共采、煤系全油气系统勘探开发,推动深部煤层气与油气协同勘探开发,已有关注和探索;煤层气与煤、油气共探共采是第5个突破方向。成果试图为新疆煤层气大规模高效勘探开发提供技术支持和工程决策参考。 展开更多
关键词 地质独特性 成因与成藏模式 工程部署方法 地质适配性技术 协同勘探开发 新疆煤层气
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关于超前谋划天然氢开发利用的思考与建议
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作者 张运东 孙乃达 +2 位作者 杨艳 刘帅奇 张珈铭 《国际石油经济》 2024年第S01期84-91,共8页
在能源转型的大背景下,氢作为清洁高效、资源丰富的新型能源被寄予厚望,其中被称为“金氢”的天然氢的勘探开发已经悄然兴起,引发全球关注。一些国家已经制定了天然氢开发利用计划,并取得较大进展。我国完全具备开发利用天然氢资源的地... 在能源转型的大背景下,氢作为清洁高效、资源丰富的新型能源被寄予厚望,其中被称为“金氢”的天然氢的勘探开发已经悄然兴起,引发全球关注。一些国家已经制定了天然氢开发利用计划,并取得较大进展。我国完全具备开发利用天然氢资源的地质条件,但针对天然氢的研究仍处于探索起步阶段。建议积极开展天然氢普查,用“超级盆地”理念勘探开发天然氢,深化天然氢成藏过程研究和潜力评价,加快相关技术研发,前瞻性布局氢能产业,为构建清洁低碳的新型能源体系做出贡献。 展开更多
关键词 天然氢 一次能源 成因 开发利用
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数学师范生数学核心素养模型建构与发展路径研究
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作者 刘喆 《教师教育论坛》 2024年第1期28-38,共11页
关注数学师范生的数学核心素养,就是关注“数学教师教育要培养什么样的人”的根本教育问题。为解决这一问题,本研究以扎根理论为方法论指导,对14位大学数学教师进行深度访谈,利用MAXQDA20软件对访谈资料进行整理、编码和统计分析,构建... 关注数学师范生的数学核心素养,就是关注“数学教师教育要培养什么样的人”的根本教育问题。为解决这一问题,本研究以扎根理论为方法论指导,对14位大学数学教师进行深度访谈,利用MAXQDA20软件对访谈资料进行整理、编码和统计分析,构建起数学师范生数学核心素养模型。该模型包括数学核心知识、数学关键能力和数学价值观念3个核心要素,以及数学学科知识、数学教学知识、数学学科能力、数学教学能力、数学信念、数学价值观6个子要素。高师院校应将发展数学核心素养作为数学人才培养的根本目标,发展路径包括:基于数学教学知识理论开发素养为本的整合课程、基于协同创新理论建立导向素养发展的教学方式、基于设计思维理论形成促进素养转化的学习过程。 展开更多
关键词 数学专业 核心素养 师范生 模型构建
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非对称变位斜齿轮参数化建模和接触应力分析
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作者 林家祥 招远聪 +1 位作者 付学中 徐海军 《机械传动》 北大核心 2024年第6期117-123,共7页
为构建非对称渐开线变位斜齿轮精确模型并分析压力角对其接触应力的影响,根据齿轮啮合原理以及C#对SolidWorks二次开发,建立了从齿条刀具展成非对称渐开线变位斜齿轮的数学模型以及精确的实体模型;同时,采用有限元法分析其齿面接触应力... 为构建非对称渐开线变位斜齿轮精确模型并分析压力角对其接触应力的影响,根据齿轮啮合原理以及C#对SolidWorks二次开发,建立了从齿条刀具展成非对称渐开线变位斜齿轮的数学模型以及精确的实体模型;同时,采用有限元法分析其齿面接触应力,并与传统公式法计算的对称变位斜齿轮齿面接触应力进行了比较。研究表明,当一侧齿面压力角相同时,非对称变位斜齿轮一侧齿面接触应力与对称变位斜齿轮十分接近,接触应力随压力角变化的增减趋势基本一致,说明了非工作侧齿面压力角的变化对工作侧齿面接触应力的影响并不明显。因此,用来计算对称变位斜齿轮齿面接触应力的传统公式法同样可以近似计算非对称变位斜齿轮的齿面接触应力。该方法可为非对称渐开线变位斜齿轮的设计提供参考。 展开更多
关键词 非对称齿轮 变位齿轮 数学模型 SOLIDWORKS二次开发 接触应力分析
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数学史如何影响教师的数学观——基于两种理论视角的案例研究 被引量:1
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作者 孙丹丹 汪晓勤 孙思雨 《数学教育学报》 CSSCI 北大核心 2024年第2期77-83,共7页
有关数学的信念、观点、规则、心理意象等统称数学观,教师认为数学是什么的观念深深影响了其认为数学应该怎样教学的观念,进而影响具体教学实践.结合数学观分类及反思性数学观模型两种理论视角,借助案例研究法,深入刻画了3位在职教师数... 有关数学的信念、观点、规则、心理意象等统称数学观,教师认为数学是什么的观念深深影响了其认为数学应该怎样教学的观念,进而影响具体教学实践.结合数学观分类及反思性数学观模型两种理论视角,借助案例研究法,深入刻画了3位在职教师数学史学习过程中数学观的变化及影响因素.研究发现:演进史—历史背景可增强教师问题解决倾向,促使教师认识到数学的动态性、人文性等;演进史—数学内容促使教师关注知识联系,增强柏拉图主义倾向,关注知识缘由,弱化工具主义倾向;枚举史—数学内容促使教师认可数学的灵活性及本质性,弱化工具主义倾向. 展开更多
关键词 数学教师 数学观 观念发展
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