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A Fast Distributed Algorithm for Association Rule Mining Based on Binary Coding Mapping Relation
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作者 CHEN Geng NI Wei-wei +1 位作者 ZHU Yu-quan SUN Zhi-hui 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期27-30,共4页
Association rule mining is an important issue in data mining. The paper proposed an binary system based method to generate candidate frequent itemsets and corresponding supporting counts efficiently, which needs only ... Association rule mining is an important issue in data mining. The paper proposed an binary system based method to generate candidate frequent itemsets and corresponding supporting counts efficiently, which needs only some operations such as "and", "or" and "xor". Applying this idea in the existed distributed association rule mining al gorithm FDM, the improved algorithm BFDM is proposed. The theoretical analysis and experiment testify that BFDM is effective and efficient. 展开更多
关键词 frequent itemsets distributed association rule mining relation of itemsets-binary data
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Dynamic Field Division of Hydrocarbon Migration,Accumulation and Hydrocarbon Enrichment Rules in Sedimentary Basins 被引量:14
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作者 PANG Xiongqi LIU Keyu +5 位作者 MA Zhongzhen JIANG Zhenxue XIANG Caifu HUO Zhipeng PANG Hong CHEN Junqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1559-1592,共34页
Hydrocarbon distribution rules in the deep and shallow parts of sedimentary basins are considerably different, particularly in the following four aspects. First, the critical porosity for hydrocarbon migration is much... Hydrocarbon distribution rules in the deep and shallow parts of sedimentary basins are considerably different, particularly in the following four aspects. First, the critical porosity for hydrocarbon migration is much lower in the deep parts of basins: at a depth of 7000 m, hydrocarbons can accumulate only in rocks with porosity less than 5%. However, in the shallow parts of basins (i.e., depths of around 1000 m), hydrocarbon can accumulate in rocks only when porosity is over 20%. Second, hydrocarbon reservoirs tend to exhibit negative pressures after hydrocarbon accumulation at depth, with a pressure coefficient less than 0.7. However, hydrocarbon reservoirs at shallow depths tend to exhibit high pressure after hydrocarbon accumulation. Third, deep reservoirs tend to exhibit characteristics of oil (-gas)-water inversion, indicating that the oil (gas) accumulated under the water. However, the oil (gas) tends to accumulate over water in shallow reservoirs. Fourth, continuous unconventional tight hydrocarbon reservoirs are distributed widely in deep reservoirs, where the buoyancy force is not the primary dynamic force and the caprock is not involved during the process of hydrocarbon accumulation. Conversely, the majority of hydrocarbons in shallow regions accumulate in traps with complex structures. The results of this study indicate that two dynamic boundary conditions are primarily responsible for the above phenomena: a lower limit to the buoyancy force and the lower limit of hydrocarbon accumulation overall, corresponding to about 10%-12% porosity and irreducible water saturation of 100%, respectively. These two dynamic boundary conditions were used to divide sedimentary basins into three different dynamic fields of hydrocarbon accumulation: the free fluid dynamic field, limit fluid dynamic field, and restrain fluid dynamic field. The free fluid dynamic field is located between the surface and the lower limit of the buoyancy force, such that hydrocarbons in this field migrate and accumulate under the influence of, for example, the buoyancy force, pressure, hydrodynamic force, and capillary force. The hydrocarbon reservoirs formed are characterized as "four high," indicating that they accumulate in high structures, are sealed in high locations, migrate into areas of high porosity, and are stored in reservoirs at high pressure. The basic features of distribution and accumulation in this case include hydrocarbon migration as a result of the buoyancy force and formation of a reservoir by a caprock. The limit fluid dynamic field is located between the lower limit of the buoyancy force and the lower limit of hydrocarbon accumulation overall; the hydrocarbon migrates and accumulates as a result of, for example, the molecular expansion force and the capillary force. The hydrocarbon reservoirs formed are characterized as "four low," indicating that hydrocarbons accumulate in low structures, migrate into areas of low porosity, and accumulate in reservoirs with low pressure, and that oil(-gas)-water inversion occurs at low locations. Continuous hydrocarbon accumulation over a large area is a basic feature of this field. The restrain fluid dynamic field is located under the bottom of hydrocarbon accumulation, such that the entire pore space is filled with water. Hydrocarbons migrate as a result of the molecular diffusion force only. This field lacks many of the basic conditions required for formation of hydrocarbon reservoirs: there is no effective porosity, movable fluid, or hydrocarbon accumulation, and potential for hydrocarbon exploration is low. Many conventional hydrocarbon resources have been discovered and exploited in the free fluid dynamic field of shallow reservoirs, where exploration potential was previously considered to be low. Continuous unconventional tight hydrocarbon resources have been discovered in the limit fluid dynamic field of deep reservoirs; the exploration potential of this setting is thought to be tremendous, indicating that future exploration should be focused primarily in this direction. 展开更多
关键词 petroliferous basins dynamic force of hydrocarbon accumulation dynamic fields ofhydrocarbon accumulation hydrocarbon accumulation mechanism hydrocarbon distribution rule
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Distribution of ground stress on Puhe Coal Mine 被引量:10
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作者 Guo Zhibiao Jiang Yulin +1 位作者 Pang Jiewen Liu Jiawei 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期139-143,共5页
Puhe Coal Mine is a typical Tertiary coal in Shenbei mining area. With an increase in mining depth, tectonic stress field becomes more complex, leading to increased deformation and failure of the soft rock roadway. St... Puhe Coal Mine is a typical Tertiary coal in Shenbei mining area. With an increase in mining depth, tectonic stress field becomes more complex, leading to increased deformation and failure of the soft rock roadway. Stress becomes an important factor of mine safety and stability. This paper analyzes the distribution of the regional tectonic field, and determines the distribution of situ stress measurement through measuring the ground stress field in the main mining area level of Puhe Coal Mine using stress relief method. The acquired in situ stress data at different locations and depths provide a reference for the rational arrangement of the stop and mine roadway supporting design, which are of great significance for the efficient safety production of the mine. 展开更多
关键词 Coal mine Tertiary Soft rock Stress Distribution rule
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Study on the influencing factors of rock-soil thermophysical parameters in shallow geothermal energy 被引量:2
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作者 ZHU Xi ZHANG Qing-lian +1 位作者 WANG Wan-li LIU Yan-guang 《Journal of Groundwater Science and Engineering》 2015年第3期256-267,共12页
Thermophysical parameters are the main parameters affecting the utilization efficiency of shallow geothermal energy. Based on the research and evaluation data of shallow geothermal energy in capital cities of China, t... Thermophysical parameters are the main parameters affecting the utilization efficiency of shallow geothermal energy. Based on the research and evaluation data of shallow geothermal energy in capital cities of China, this paper analyzes the differences between two testing methods and finds that data measured in in-situ thermal conductivity test is closer to the actual utilization. This paper analyzes the influencing factors of thermophysical parameters from lithology, density, moisture content and porosity: The thermal conductivity coefficient of bedrock is generally higher than Quaternary system loose bed soil; as for the coefficient of bedrock, dolomite, shale and granite are higher while gabbro, sandstone and mudstone are lower; as for the coefficient of loose bed, pebble and gravel are higher while clay and silt are lower. As the particle size of sand decreases, the thermal conductivity coefficient declines accordingly. The thermal conductivity coefficient increases linearly with growing density and decreases in logarithm with growing moisture content as well as porosity; specific heat capacity decreases in logarithm with growing density, increases in power exponent with growing moisture content and decreases linearly with growing porosity. The thermal conductivity coefficient is high when hydrodynamic condition is good and vice versa. The conclusions of this paper have guiding significance for the research, evaluation and development of shallow geothermal energy in other areas. 展开更多
关键词 Shallow geothermal energy Thermophysical property Influencing factor Distribution rule
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Effects of Ultrasonic Field on Microstructures and Properties of Semi-solid AZ91D Magnesium Alloy
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作者 陈国平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期555-560,共6页
The microstructure distribution rule of semi-solid AZ91D alloy treated by ultrasonic was researched, and mechanical properies of specimens before and after ultrasonic treatment were investigated further.Semi-solid AZ9... The microstructure distribution rule of semi-solid AZ91D alloy treated by ultrasonic was researched, and mechanical properies of specimens before and after ultrasonic treatment were investigated further.Semi-solid AZ91D melt specimens were processed by ultrasonic under different powers, and its microstructures and mechanical properties at different sampling points in specimens were obtained. The experimental results show that the microstructure of AZ91D alloy at different sampling points under the same ultrasonic power is different in grain size and shape, and there is also great difference among their microstructures at the same sampling point under different ultrasonic powers. AZ91D alloy treated by ultrasonic can obtain increment in both tensile strength and plasticity. Under same ultrasonic power, mechanical properties of specimen at different sampling points have obvious difference, and regularity for change of mechanical properties everywhere is similar to regularity for change of grain size and shape everywhere. 展开更多
关键词 magnesium alloy AZ91D ultrasonic treatment semi-solid structure distribution rule
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Basic properties of saline soil in Da'an, western Jilin, China
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作者 Xin Zhou Qing Wang +2 位作者 XueFei Zhang TianWen Yu XuDong Zhang 《Research in Cold and Arid Regions》 CSCD 2015年第5期568-572,共5页
This paper studied the basic properties of saline soil at different depths of a sampling site in Da'an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyse... This paper studied the basic properties of saline soil at different depths of a sampling site in Da'an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyses of grain size distribution, mineral composition, soil physical properties, soluble salt concent, pH, organic content and cation exchange capacity were conducted. Through these experiments, the distribution rule of each property and their causes are discussed. These results could provide a fundamental base for the study of moisture migration. 展开更多
关键词 saline soil basic properties distribution rule moisture migration
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PH_3 monitoring in Arctic and Dalian bay areas
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作者 封颖 Wang Qiang +1 位作者 Yao Ziwei Geng Jinju 《High Technology Letters》 EI CAS 2010年第4期437-440,共4页
In this paper, we use pre-column 2 times low-temperature cryo-trap enrichment--gas chromatography(GC) /nitrogen and phosphorus detector(NPD)to detect and analyze phosphine in Arctic pole area for the first time. T... In this paper, we use pre-column 2 times low-temperature cryo-trap enrichment--gas chromatography(GC) /nitrogen and phosphorus detector(NPD)to detect and analyze phosphine in Arctic pole area for the first time. The results show phosphine exists in all of the samples in Arctic pole biosphere and phosphine concentration in Arctic atmosphere is between 18.54- 132.18 ng/m^3, almost the same as that in Antarctic atmosphere; phosphine concentration in Dalian bay sea surface sediments is between 116. 8- 554.3 ng/kg, almost the same as that reported in Jiao-zhou bay. Our research of phosphine will shed new light on the mechanisms showing how the phosphorus supplement influences the biogeochemical cycle and global warming. 展开更多
关键词 PHOSPHINE Arctic pole area Dalian bay area distribution rules DETECT
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Medical Image Analysis Using Deep Learning and Distribution Pattern Matching Algorithm
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作者 Mustafa Musa Jaber Salman Yussof +3 位作者 Amer S.Elameer Leong Yeng Weng Sura Khalil Abd Anand Nayyar 《Computers, Materials & Continua》 SCIE EI 2022年第8期2175-2190,共16页
Artificial intelligence plays an essential role in the medical and health industries.Deep convolution networks offer valuable services and help create automated systems to perform medical image analysis.However,convol... Artificial intelligence plays an essential role in the medical and health industries.Deep convolution networks offer valuable services and help create automated systems to perform medical image analysis.However,convolution networks examine medical images effectively;such systems require high computational complexity when recognizing the same disease-affected region.Therefore,an optimized deep convolution network is utilized for analyzing disease-affected regions in this work.Different disease-relatedmedical images are selected and examined pixel by pixel;this analysis uses the gray wolf optimized deep learning network.This method identifies affected pixels by the gray wolf hunting process.The convolution network uses an automatic learning function that predicts the disease affected by previous imaging analysis.The optimized algorithm-based selected regions are further examined using the distribution pattern-matching rule.The pattern-matching process recognizes the disease effectively,and the system’s efficiency is evaluated using theMATLAB implementation process.This process ensures high accuracy of up to 99.02%to 99.37%and reduces computational complexity. 展开更多
关键词 Artificial intelligence medical field gray wolf-optimized deep convolution networks distribution pattern-matching rule
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Structural bionic design for high-speed machine tool working table based on distribution rules of leaf veins 被引量:7
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作者 XING DengHai CHEN WuYi +1 位作者 ZHAO Ling MA JianFeng 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第8期2091-2098,共8页
High-speed machine tool working table restrains the machining accuracy and machining efficiency,so lightweight design of the table is an important issue.In nature,leaf has developed a plate structure that maximizes th... High-speed machine tool working table restrains the machining accuracy and machining efficiency,so lightweight design of the table is an important issue.In nature,leaf has developed a plate structure that maximizes the surface-to-volume ratio.It can be seen as a plate structure stiffened by veins.Compared with a high-speed machine tool working table,leaf veins play a role of supporting part which is similar to that of stiffening ribs,and they can provide some new design ideas for lightweight design of the table.In this paper,distribution rules of leaf veins were investigated,and a structural bionic design for the table was achieved based on regulation of leaf veins.First,statistical analysis on geometric structure of leaf veins was carried out,and four distribution rules were obtained.Then,relevant mechanical models were developed and analyzed in finite element software.Based on the results from mechanical analysis on those relevant models,the four distribution rules were translated into the design rules and a structural bionic design for the working table was achieved.Both simulation and experimental verifications were carried out,and results showed that the average displacement of the working table was reduced by about 33.9%. 展开更多
关键词 structural bionic design lightweight design distribution rules of leaf veins specific stiffness working table
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A secure and high-performance multi-controller architecture for software-defined networking
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作者 Huan-zhao WANG Peng ZHANG +2 位作者 Lei XIONG Xin LIU Cheng-chen HU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第7期634-646,共13页
Controllers play a critical role in software-defined networking(SDN).However,existing singlecontroller SDN architectures are vulnerable to single-point failures,where a controller's capacity can be saturated by fl... Controllers play a critical role in software-defined networking(SDN).However,existing singlecontroller SDN architectures are vulnerable to single-point failures,where a controller's capacity can be saturated by flooded flow requests.In addition,due to the complicated interactions between applications and controllers,the flow setup latency is relatively large.To address the above security and performance issues of current SDN controllers,we propose distributed rule store(DRS),a new multi-controller architecture for SDNs.In DRS,the controller caches the flow rules calculated by applications,and distributes these rules to multiple controller instances.Each controller instance holds only a subset of all rules,and periodically checks the consistency of flow rules with each other.Requests from switches are distributed among multiple controllers,in order to mitigate controller capacity saturation attack.At the same time,when rules at one controller are maliciously modified,they can be detected and recovered in time.We implement DRS based on Floodlight and evaluate it with extensive emulation.The results show that DRS can effectively maintain a consistently distributed rule store,and at the same time can achieve a shorter flow setup time and a higher processing throughput,compared with ONOS and Floodlight. 展开更多
关键词 Software-defined networking(SDN) Security MULTI-CONTROLLER distributed rule store
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The porosity origin of dolostone reservoirs in the Tarim, Sichuan and Ordos basins and its implication to reservoir prediction 被引量:27
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作者 ZHAO WenZhi SHEN AnJiang +3 位作者 ZHENG JianFeng QIAO ZhanFeng WANG XiaoFang LU JunMing 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2498-2511,共14页
Origin of dolostone remained a controversial subject, although numerous dolomitization models had been proposed to date. Because of the dolomitization's potential to be hydrocarbon reservoirs, one debatable issue was... Origin of dolostone remained a controversial subject, although numerous dolomitization models had been proposed to date. Because of the dolomitization's potential to be hydrocarbon reservoirs, one debatable issue was the role of dolomitization in porosity construction or destruction. Based upon case studies of dolostone reservoirs in various geological settings such as evaporative tidal flat (Ordos Basin, NW China), evaporative platform (Sichuan Basin, SW China), and burial and hydrothermal diagenesis (Tarim Basin, NW China), here we systematically discuss the origin of porosity in dolostone reservoirs. Contrary to traditional concepts, which regarded dolomitization as a significant mechanism for porosity creation, we found two dominant factors controlling reservoir development in dolostones, i.e., porosity inherited from precursor carbonates and porosity resulted from post-dolomitization dissolution. Actually, dolomitization rarely had a notable effect on porosity creation but rather in many cases destroyed pre-existing porosity such as saddle dolostone precipitation in vugs and fractures. Porosity in dolostones associated with evaporative tidal flat or evaporative platform was generally created by subaerial dissolution of evaporites and/or undolomitized components. Porosity in burial dolostones was inherited mostly from precursor carbonates, which could be enlarged due to subsequent dissolution. Intercrystalline porosity in hydrothermal dolostones was either formed during dolo- mitization or inherited from precursor carbonates, whereas dissolution-enlarged intercrystalline pores and/or vugs were usually interpreted to be the result of hydrothermai alteration. These understandings on dolostone porosity shed light on reservoir pre- diction. Dolostone reservoirs associated with evaporative tidal flat were laterally distributed as banded or quasi-stratified shapes in evaporite-bearing dolostones, and vertically presented as multi-interval patterns on tops of shallowing-upward cycles Dolostone reservoirs associated with evaporative platform commonly occurred along epiplatforms or beneath evaporite beds, and vertically presented as multi-interval patterns in dolostones and/or evaporite-bearing dolostones of reef/shoal facies. Con- strained by primary sedimentary facies, burial dolostone reservoirs were distributed in dolomitized, porous sediments of reef/shoal facies, and occurred vertically as multi-intervai patterns in crystalline dolostones on tops of shallowing-upward cy- cles. Hydrothermal dolomitization was obviously controlled by conduits (e.g., faults, unconformities), along which lenticular reservoirs could develop. 展开更多
关键词 dolostone reservoirs DOLOMITIZATION reservoir distribution rule Tarim Basin Sichuan Basin Ordos Basin
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CFD simulation of sucrose flow field in the stem of greenhouse tomato seedling
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作者 Jiheng Ni Jingtao Dong +1 位作者 Ikram Ullah Hanping Mao 《International Journal of Agricultural and Biological Engineering》 SCIE CAS 2022年第1期111-115,共5页
Sucrose is the main constituent of assimilation transport from source to sink.In order to study the transport mechanism of sucrose,the sucrose at stem was taken as a research object and the sucrose flow field in tomat... Sucrose is the main constituent of assimilation transport from source to sink.In order to study the transport mechanism of sucrose,the sucrose at stem was taken as a research object and the sucrose flow field in tomato stem was analyzed using CFD ANSYS FLUENT simulation.The results showed that the sucrose pressure distribution was lower at bottom node and higher at middle node.The velocity of sucrose at different nodes was higher at the bottom node and lower at middle node and assimilation flow direction of the first,second,and third leaf from the bottom was towards the roots.The result of verification experiment showed that sucrose content measured at different nodes was higher at middle node than that of bottom node.Results of this study confirmed that ANASYS FLUENT can better simulate sucrose migration in greenhouse tomato stem.This study provides a new method for studying the partitioning mechanism of tomato assimilates in greenhouse. 展开更多
关键词 greenhouse tomato sucrose flow field computational fluent dynamic rule of distribution
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