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Simulation of the Accumulation Process of Biogenic Gas Hydrates in the Shenhu Area of Northern South China Sea 被引量:3
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作者 LIAO Jing GONG Jianming +4 位作者 Lü Wanjun WU Nengyou YUE Baojing LUAN Xiwu HU Gaowei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2285-2286,共2页
Previous work has largely discussed the relations between sediment structures and accumulation of gas hydrates in the Shenhu area of South China Sea, but has not documented why the gas hydrates occurred at the seafloo... Previous work has largely discussed the relations between sediment structures and accumulation of gas hydrates in the Shenhu area of South China Sea, but has not documented why the gas hydrates occurred at the seafloor topographic highs. Many gas hydrate exploration examples abroad also indicate that the saturation of gas hydrates was higher at seafloor topographic highs. This work aims to understand why gas hydrates accumulated at topographic highs and why their saturation is higher. 展开更多
关键词 area Simulation of the Accumulation process of Biogenic Gas Hydrates in the Shenhu area of Northern South China Sea THAN
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Analysis on the Heavy Snow Weather Process in Benxi Area 被引量:1
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作者 KOU Si-cong CAO Wen 《Meteorological and Environmental Research》 CAS 2011年第1期24-27,共4页
[Objective] The aim was to study the formation and development of a heavy snow in Benxi area. [Method] Based on conventional meteorological data, the formation and development of a heavy snow in Benxi area from Decemb... [Objective] The aim was to study the formation and development of a heavy snow in Benxi area. [Method] Based on conventional meteorological data, the formation and development of a heavy snow in Benxi area from December 4th to 5th in 2009 were analyzed from the aspects of weather situation evolution and physical quantity field feature. [Result] The heavy snow was caused by upper trough and North China cyclone. In this process, there was upper level divergence and lower level convergence over Benxi area, and it was warm at low attitude and cold at high attitude; southwest jet at low attitude transported water vapor from Bohai Sea to eastern Liaoning, which provided good water vapor condition for snow, but it didn’t reach heavy snow due to inadequate ascending force. The development of Ural Mountains high ridge played an important role in the snow process and the strengthened high ridge moving northward was beneficial to the southward movement of cold air and deepening of upper trough. Analysis on physical quantity field could provide reference for predicting beginning and ending time and strength of heavy snow. [Conclusion] The study could provide basis for the forecast of heavy snow. 展开更多
关键词 Heavy snow Weather situation Physical quantity process analysis Benxi area China
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Evaluation of Rainwater Harvesting Methods and Structures Using Analytical Hierarchy Process for a Large Scale Industrial Area 被引量:1
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作者 V. JOTHIPRAKASH Mandar V. SATHE 《Journal of Water Resource and Protection》 2009年第6期427-438,共12页
In India, with ever increasing population and stress on natural resources, especially water, rejuvenation of rainwater harvesting (RWH) technique which was forgotten over the days is becoming very essential. Large num... In India, with ever increasing population and stress on natural resources, especially water, rejuvenation of rainwater harvesting (RWH) technique which was forgotten over the days is becoming very essential. Large number of RWH methods that are available in the literature are demand specific and site specific, since RWH system depends on the topography, land use, land cover, rainfall and demand pattern. Thus for each and every case, a detailed evaluation of RWH structures is required for implementation, including the analy-sis of hydrology, topography and other aspects like site availability and economics, however a common methodology could be evolved. The present study was aimed at evaluation of various RWH techniques in order to identify the most appropriate technique suitable for a large scale industrial area to meet its daily wa-ter demand. An attempt is made to determine the volume of water to be stored using mass balance method, Ripple diagram method, analytical method, and sequent peak algorithm method. Based on various satisfying criteria, analytical hierarchy process (AHP) is employed to determine the most appropriate type of RWH method and required number of RWH structures in the study area. If economy alone is considered along with hydrological and site specific parameters, recharging the aquifer has resulted as a better choice. However other criteria namely risk, satisfaction in obtaining required volume of water for immediate utilization etc. has resulted in opting for concrete storage structures method. From the results it is found that AHP, if used with all possible criteria can result in a better tool for evaluation of RWH methods and structures. This RWH structures not only meets the demand but saves transportation cost of water and reduces the dependability of the industry on irrigation reservoir. Besides monetary benefits it is hoped that the micro environment inside the industry will improve due to the cooling effect of the stored water. 展开更多
关键词 RAIN Water HARVESTING ANALYTICAL HIERARCHY process Large SCALE Industrial area AQUIFER
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A Study on Law of Change of Real Contact Area of Friction during Transition Process
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作者 金长善 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第1期7-10,共4页
AStudyonLawofChangeofRealContactAreaofFrictionduringTransitionProcess(金长善)¥JINChangshan(金长善)(Dept.ofControland... AStudyonLawofChangeofRealContactAreaofFrictionduringTransitionProcess(金长善)¥JINChangshan(金长善)(Dept.ofControlandAutomationintheMe... 展开更多
关键词 ss: TRANSITION process FRICTION REAL area of CONTACT
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Study on Winter Operation Process of the Surface Flow Constructed Wetland in Tianjin Area
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作者 Xiaodan Qin Yichao Sun +5 位作者 Li Li Xiaolong Shao Dan Yu Qiongqiong Liu Honglei Liu Lin Han 《Meteorological and Environmental Research》 CAS 2013年第7期43-46,共4页
[Objective] The research aimed to study winter operation process of the surface flow constructed wetland in "rianjin area. [Method] In view of climate characteristics in Tianjin, by the way of running under the ice, ... [Objective] The research aimed to study winter operation process of the surface flow constructed wetland in "rianjin area. [Method] In view of climate characteristics in Tianjin, by the way of running under the ice, winter operation experiment of the surface flow constructed wetland in Tianjin was conducted, with the expectation to get some useful process parameters to run such systems in North China in winter. [ Result] Although purification effect of the sewage by surface flow constructed wetland in winter was worse than that in other seasons ( average reduction of about 20%), surface flow constructed wetland running under the ice was feasible in Tianjin area. When surface flow constructed wetland in North China ran under ice in winter, it was suggested that the outlet must be located in a low position to prevent to be completely frozen, and running water depth should not be less than 50 -60 cm. The hydraulic load could be raised on the basis of reflux, and hydraulic retention time should maintain less than 4 d to keep water-soil interface not freezing. Inlet water depth should be increased as much as possible to improve temperature in the system. V Conclusion1 The research could provide reference for promotion and application of the surface flow constructed wetland in North China. 展开更多
关键词 Surface flow constructed wetland Operation process WINTER Tianjin area China
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FE Study for Reducing Forming Forces and Flat End Areas of Cylindrical Shapes Obtained by the Roll-Bending Process
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作者 Quan Hoang Tran Henri Champliaud Zhengkun Feng Thien My Dao 《Journal of Mechanics Engineering and Automation》 2014年第6期467-475,共9页
关键词 弯曲过程 FE 形状 成形力 LS-DYNA软件 圆柱 ANSYS 敏感性分析
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Hydrocarbon Accumulation Process in the Marine Strata in Jianghan Plain Area, Middle China
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作者 XU Guosheng ZHANG Lijun +4 位作者 GONG Deyu WANG Guozhi YUAN Haifeng LI Changhong HU Xiaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第3期878-893,共16页
Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z-C2, C2-O, S, D--C, P and T1, c... Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z-C2, C2-O, S, D--C, P and T1, can be identified with each epoch. The geology, stratigraphy, drilling, oil testing and other basic data as well as the measured inclusion and strontium isotope data in the study area are used in the analysis of the formation and evolution process of marine petroliferous reservoirs in the Jianghan Plain area. This study aims to provide a scientific basis for the further exploration of hydrocarbons in the Jianghan Plain and reduce the risks by analyzing the key factors for hydrocarbon accumulation in the marine strata. Our findings show that in the Lower Palaeozoic hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the early period of the Early Yanshanian, and the hydrocarbon reservoir was destroyed in the middle-late period of the Early Yanshanian. In the Lower Triassic-Carboniferous hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the Early Yanshanian, and the hydrocarbon reservoir suffered destruction from the Late Yanshanian to the Early Himalayanian. The preservation conditions of the marine strata in the Jianghan Plain area have been improved since the Late Himalayanian. However, because all source beds have missed the oil/gas generation fastigium and lost the capacity to generate secondary hydrocarbon, no reaccumulation of hydrocarbons can be detected in the study area's marine strata. No industrially exploitable oil/gas reservoir has been discovered in the marine strata of Jianghan Plain area since exploration began in 1958. This study confirms that petroliferous reservoirs in the marine strata have been completely destroyed, and that poor preservation conditions are the primary factor leading to unsuccessful hydrocarbon exploration. It is safely concluded that hydrocarbon exploration in the marine strata of the study area is quite risky. 展开更多
关键词 marine strata reservoir caprock unithydrocarbon accumulation process reservoirevolution Jianghan Plain area Middle China
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喀什地区复播小米的品质评价
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作者 高强 杨艳 +6 位作者 路子峰 严青青 张龑 徐麟 陈润峰 郑立鹏 周伟 《山西农业科学》 2024年第3期9-14,共6页
为探究喀什地区复播的不同品种谷子小米营养品质的差异,试验以不同来源的4个谷子品种作为分析对象,对小米中的9种矿质元素Na、Mg、K、Ca、Mn、Fe、Cu、Zn、Se含量进行检测,并对其4种营养指标脂肪酸、粗蛋白、粗脂肪、淀粉含量进行检测分... 为探究喀什地区复播的不同品种谷子小米营养品质的差异,试验以不同来源的4个谷子品种作为分析对象,对小米中的9种矿质元素Na、Mg、K、Ca、Mn、Fe、Cu、Zn、Se含量进行检测,并对其4种营养指标脂肪酸、粗蛋白、粗脂肪、淀粉含量进行检测分析,最后对其生产加工方向进行综合预测。结果表明,各元素含量在不同品种谷子间差异显著,其中Na含量为8.24~31.18μg/g,Mg含量为869.42~1 580.23μg/g,K含量为2 326.80~5 033.01μg/g,Ca含量为110.64~395.88μg/g,Mn含量为11.39~21.11μg/g,Fe含量为15.94~57.46μg/g,Cu含量为0~7.51μg/g,Zn含量为15.10~35.94μg/g,Se含量为0.070 7~0.176 8μg/g。小米矿质元素总量范围为3 365.10~6 874.92μg/g,变异系数为25.95%;不饱和脂肪酸含量丰富而且在不同品种间差异显著;粗蛋白、粗脂肪、淀粉的含量范围分别是12.9%~13.69%、4.54%~6.02%、68.8%~76.76%,变异系数分别为5.00%,11.42%和4.91%。不同品种谷子小米直链淀粉含量差异不大,对其糊化温度与胶稠度分析后发现,陇谷29易蒸煮、适口性更好。不同品种谷子小米的营养品质存在差异性,陇谷29总体表现优异,晋谷21次之,二者均可作为企业生产的储备品种。 展开更多
关键词 复播 小米 营养指标 生产加工 喀什地区
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Modeling of Deposition Process of Particulate Organic Matter (POM) with Sand on Vegetated Area in a River
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作者 Makiko Obana Ho-Seong Jeon Tetsuro Tsujimoto 《Journal of Water Resource and Protection》 2014年第14期1290-1296,共7页
The transport and deposition of particulate organic matter (POM) in river streams has recently received much attention as one of important ecological processes in rivers. We focused on interacted behaviors of sand par... The transport and deposition of particulate organic matter (POM) in river streams has recently received much attention as one of important ecological processes in rivers. We focused on interacted behaviors of sand particles in bed load and POM in vegetated area on sand bars. The purpose of this study is to clarify the characteristics of deposition of POM with bed load on sandbars with the riparian vegetation. A basic experiment on POM transport and deposition with vegetation is conducted in a laboratory flume. It demonstrates that several issues still remain to be future investigated. In particular, the shear due to the bed roughness in the vegetated area and the transport and deposition process of sand particles and POM are required to be described by the proper modeling which will be introduced into a simulation model of various fluvial processes. The main results of this study are that ripples are formed by bed load in riparian vegetation and POM deposition is promoted by ripple behavior. Based on these results, the POM deposition with ripples in vegetated area is described by a conceptual model which will affect various aspects in ecosystem management based on fluvial processes. 展开更多
关键词 Modeling DEPOSITION process PARTICULATE ORGANIC MATTER (POM) SAND Vegetated area
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黔西南雄武地区铀矿化与有机流体的成因联系
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作者 邱林飞 吴玉 +8 位作者 李子颖 蒋宏 徐伟 韩文文 解波 郭建 孙祥 黎丕林 邱锦鸿 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第2期352-367,共16页
在黔西南地区,前人针对构造演化、油气流体、金矿床成矿流体和成矿模式等方面开展了大量的研究,但铀矿床研究方面还十分薄弱,尤其针对有机流体与铀成矿的关系还未开展研究。本次研究在野外地质调查基础上,对黔西南雄武地区大际山铀矿床... 在黔西南地区,前人针对构造演化、油气流体、金矿床成矿流体和成矿模式等方面开展了大量的研究,但铀矿床研究方面还十分薄弱,尤其针对有机流体与铀成矿的关系还未开展研究。本次研究在野外地质调查基础上,对黔西南雄武地区大际山铀矿床及大梨树铀矿床中典型的矿石与蚀变围岩样品开展了显微岩相学、扫描电镜‒能谱分析、电子探针、流体包裹体、激光拉曼、稳定同位素等方面研究。宏观上,铀矿体的中心部位往往呈黑色,矿体两侧呈灰色、灰褐色,矿体中心向两侧颜色逐渐变浅。镜下研究发现,铀矿物、黄铁矿等金属矿物与黑色的有机质紧密共生。激光拉曼分析指示,这些有机质经历的最高温度为185~237℃,等效镜质体反射率指示有机质处于高成熟‒过成熟阶段,具有焦沥青的特征。铀矿体外围蚀变带中饱含显示强浅蓝色荧光的轻质油,指示富烃类有机流体与成矿物质可能为同一来源,均为含铀有机流体演化而成。铀矿石中黑色有机质的^(13)C值与其赋矿碳酸盐岩表现出明显的异源特征,且与当地古油藏的C同位素具有相似性,指示焦沥青可能来源于深部侵位的古油藏。铀矿物微区年代学与有机质Re-Os年代学的研究结果在误差范围内基本一致,均为喜山期,进一步指示铀矿物和有机质是同时代地质作用的产物。黔西南雄武地区铀的沉淀应该与油气裂解‒分异作用相关,其铀矿成矿作用既不是以往认为的沉积成岩型,也不是沉积成岩叠加淋积‒热液改造型,而应该是构造作用下、深部渗出含铀富有机质成矿流体形成的渗出碳酸盐岩型铀矿床。成矿过程中,铀钼等多金属可能以微纳米超显微结构的形式随有机流体共同迁移,在温压条件变化的情况下,含矿的富烃类有机流体发生裂解‒分异作用,致使铀、黄铁矿等金属物质与重质组分(沥青)残留于破碎带或构造裂隙中而发生铀矿化,而轻质组分(轻质油)发生逃逸,部分以包裹体或孔隙流体的形式捕获于构造带或上覆地层中。 展开更多
关键词 烃类流体 裂解‒分异作用 大际山铀矿床 雄武地区 黔西南
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基于图像处理的水培生菜冠层图像叶面积估测研究
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作者 杨娟 赵汗青 +3 位作者 马新明 钱婷婷 张滢钰 王宁 《上海农业学报》 2024年第1期116-124,共9页
为实现精准、高效、无损地获取植物工厂环境下水培生菜相关长势参数叶面积(Leaf area,LA),基于数字图像处理和机器学习回归方法建立单株水培生菜冠层图像LA估测模型。首先,通过智能手机获取2个生菜品种不同生长期的冠层可见光图像,利用P... 为实现精准、高效、无损地获取植物工厂环境下水培生菜相关长势参数叶面积(Leaf area,LA),基于数字图像处理和机器学习回归方法建立单株水培生菜冠层图像LA估测模型。首先,通过智能手机获取2个生菜品种不同生长期的冠层可见光图像,利用Photoshop图像处理软件将原始图像统一剪裁为900像素×900像素大小,采用中值滤波(MedianBlur)法对剪裁后的图像进行去噪运算,将RGB图像转化为HSV颜色空间,再采用mask掩膜法分割彩色图像;然后,利用图像法获取单株生菜LA实测值,构建以LA实测值为因变量,以生菜冠层投影面积(Projected leaf area,PLA)为自变量的线性回归(Linear regression,LR)模型和以全局图像特征(颜色、形状、纹理等)为自变量的支持向量回归(Support vector regression,SVR)、多元线性回归(Multiple linear regression,MLR)和随机森林(Random forest,RF)等LA估测模型进行对比分析;最后,采用决定系数(Coefficient of determination,R^(2))和均方根误差(Root mean square error,RMSE)评估模型的准确性。结果表明:RF模型估测效果最好,对于生菜品种‘绿萝’单株LA估测结果的R^(2)为0.9714、RMSE为8.89 cm2,对于品种‘碧霄’估测结果的R^(2)为0.9201、RMSE为23.34 cm2。本研究验证了RF回归模型能够较准确地估测生菜单株叶面积,可为植物工厂水培生菜LA无损估测提供新的解决方案和研究基础。 展开更多
关键词 生菜 植物工厂 叶面积 图像处理 多元线性回归 支持向量回归 随机森林
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长江口横沙地区演化过程及保护利用思考
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作者 郭兴杰 《上海国土资源》 2024年第1期16-20,26,共6页
长江口横沙地区的保护和利用一直是近年来的热门话题。本文对横沙岛、横沙新洲的成陆过程以及浅滩的近期演化特征进行了总结和回顾,基于国家战略和前人的利用设想,提出了横沙地区目前面临的灾害和未来利用需要论证的制约因素。横沙岛于1... 长江口横沙地区的保护和利用一直是近年来的热门话题。本文对横沙岛、横沙新洲的成陆过程以及浅滩的近期演化特征进行了总结和回顾,基于国家战略和前人的利用设想,提出了横沙地区目前面临的灾害和未来利用需要论证的制约因素。横沙岛于1958年定界成陆,横沙新洲(东滩)在历史大洪水切割以及航道工程和促淤圈围等作用下于2021年成陆,横沙浅滩目前“长高不长大”,处于萎缩性演化态势。文章基于“长江大保护”国家战略,总结了前人提出的一些利用设想,认为需要综合研判横沙地区的保护利用模式。目前横沙地区主要面临流域输沙偏低和海平面上升带来的浅滩侵蚀问题,建议结合固沙保滩工程利用周围航道的疏浚土资源,未来利用也需要深入研究横沙地区生态保护、基底稳定、航道冲淤、盐水入侵以及极端气候等承载力问题。 展开更多
关键词 长江口 横沙地区 演化过程 保滩工程 利用思考
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基于改进方法的承德地表水环境质量评价
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作者 张胜 张涛 +4 位作者 段雯瑜 徐利 顾金洋 张炜 李思敏 《干旱区研究》 CSCD 北大核心 2024年第1期50-59,共10页
为客观反映地表水水质状况,采用层次分析法和熵权法组合赋权以及加权平均综合评价原则改进模糊综合评价法,并与单因子评价法、内梅罗指数法、传统模糊综合评价法进行比较,评价承德地区地表水环境质量。结果表明:2021年承德地区地表水水... 为客观反映地表水水质状况,采用层次分析法和熵权法组合赋权以及加权平均综合评价原则改进模糊综合评价法,并与单因子评价法、内梅罗指数法、传统模糊综合评价法进行比较,评价承德地区地表水环境质量。结果表明:2021年承德地区地表水水质有明显的时空差异性,除7—9月的部分断面水质为较差外,其余断面水质均在Ⅰ~Ⅲ类;影响承德地区地表水水质的主要因子为COD_(Mn)和TP;单因子评价法和内梅罗指数法无法反映整体水质状况,改进的模糊综合评价法相较于传统模糊综合评价法兼顾了各污染因子间相互作用,并弱化了个别水质指标对评价结果的影响,且能够对同一类别水质进行排序,更适用于承德地区地表水环境质量评价。 展开更多
关键词 水质评价 改进的模糊综合评价法 层次分析法 熵权法 承德地区
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滇龙胆的本草考证
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作者 杨雁 金航 +4 位作者 杨斌 王馨 马维思 金鹏程 李林玉 《中国民族民间医药》 2024年第1期55-61,83,共8页
目的:研究历代典籍对滇龙胆的文献记载,对滇龙胆进行本草考证,以期为滇龙胆的开发利用提供参考。方法:通过查阅历代本草典籍,结合现代研究文献,对滇龙胆的名称、基原、产地变迁、采收加工以及品质评价进行系统的梳理、考证。结果:经考证... 目的:研究历代典籍对滇龙胆的文献记载,对滇龙胆进行本草考证,以期为滇龙胆的开发利用提供参考。方法:通过查阅历代本草典籍,结合现代研究文献,对滇龙胆的名称、基原、产地变迁、采收加工以及品质评价进行系统的梳理、考证。结果:经考证,滇龙胆始载于《滇南本草》,别名坚龙胆、龙胆草、苦草等,为龙胆科龙胆属植物,基原植物为滇龙胆,是《中华人民共和国药典》龙胆药材的基原植物之一;主产于云南,临沧是其道地产区;滇龙胆一般于秋冬两季采收;加工多以产地初加工为主,即将滇龙胆清洗后阴干或晒干;历代本草典籍中对其质量评价的记载非常少,以“形如枯骨”“根肥长”“脂润”“味苦”“粘牙”作为质量好坏的评价标准,现代主要以龙胆苦苷含量作为龙胆药材质量评价的主要手段之一,辅助以外观性状等的观测。结论:考证结果将为今后滇龙胆的开发利用提供参考。 展开更多
关键词 滇龙胆 本草考证 名称 基原 产地 采收加工 品质评价
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百年中国现代化进程的历史反思与时代性超越——兼论“三农”问题的历史累积与乡村振兴的实现
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作者 王先明 《理论与现代化》 2024年第1期65-75,共11页
以洋务运动为始,中国走上以工业化为主导的现代化道路。但是,中国传统文明与西方式现代化取向之间形成历史“悖论”,这种悖论关系更突出体现在城乡背离化发展态势上。如何走出具有中国特色的现代化道路,并从根本上摆脱这一困境,一直是... 以洋务运动为始,中国走上以工业化为主导的现代化道路。但是,中国传统文明与西方式现代化取向之间形成历史“悖论”,这种悖论关系更突出体现在城乡背离化发展态势上。如何走出具有中国特色的现代化道路,并从根本上摆脱这一困境,一直是中国共产党的历史使命之一。在总结和汲取近代以来中国现代化发展经验和教训的基础上,中国共产党领导人民成功走出中国式现代化道路。中国共产党通过乡村振兴战略的全面实施,从根本上突破近代以来百余年的“三农”困境,从而解决了中国现代化发展中的“悖论”问题。 展开更多
关键词 现代化进程 “三农”问题 城乡背离化 乡村振兴
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煤矿采动稳定区煤层气开发区块经济评价技术
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作者 李日富 刘佩 戴林超 《煤炭技术》 CAS 2024年第1期273-276,共4页
针对我国煤矿采动稳定区煤层气开发区块评价技术缺乏,难以有效指导经济开发应用这一问题,基于煤层气开发效果与综合效益,分析了采动稳定区煤层气开发区块评价关键参数,构建了考虑技术进步等动态影响因素的煤层气开发区块经济评价指标体... 针对我国煤矿采动稳定区煤层气开发区块评价技术缺乏,难以有效指导经济开发应用这一问题,基于煤层气开发效果与综合效益,分析了采动稳定区煤层气开发区块评价关键参数,构建了考虑技术进步等动态影响因素的煤层气开发区块经济评价指标体系,采用层次分析方法获得了各单项指标的相对权重,并提出了开发区块最大隶属原则经济评价方法。应用试验表明,该经济评价方法可为煤矿采动稳定区煤层气开发决策提供可靠指导。 展开更多
关键词 采动稳定区 煤层气开发 层次分析法 经济评价技术 区块评价模型
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基于图像形态学的焊缝区域提取与对比度提升技术
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作者 刘欢 刘骁佳 +3 位作者 赵耀邦 王宁 罗志强 危荃 《中国材料进展》 CAS CSCD 北大核心 2024年第2期175-180,共6页
铝板焊接后可使用X射线进行焊缝内部缺陷检测,由于X射线成像存在噪声多、对比度低、焊缝区域边缘模糊、焊缝区域与背景区域灰度分布较为相似等问题,使用传统边缘检测方法效果欠佳。提出了一种自动提取焊缝区域并提高其对比度的方法,通... 铝板焊接后可使用X射线进行焊缝内部缺陷检测,由于X射线成像存在噪声多、对比度低、焊缝区域边缘模糊、焊缝区域与背景区域灰度分布较为相似等问题,使用传统边缘检测方法效果欠佳。提出了一种自动提取焊缝区域并提高其对比度的方法,通过去噪处理、边缘检测、形态学操作等步骤,最终确定焊缝区域位置,并对焊缝区域内像素值进行线性变换,提高了焊缝区域的对比度。实验结果表明,该方法针对大批量的铝板X射线图片,都能够自动提高焊缝区域的对比度,具有良好的鲁棒性和准确性。 展开更多
关键词 图像处理 X射线 焊缝区域 梯度 对比度
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卷烟滤棒成型加工区域集控系统实现
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作者 段青娜 沙利波 +3 位作者 罗运河 邱潇 高阔 杨四林 《机械工程与自动化》 2024年第3期147-149,共3页
针对滤棒成型作业区分散、设备种类多、制造厂家和数量多、接口协议复杂且不统一以及海量数据变量难识别等问题,设计并开发了基于OPC UA架构和实时内存数据库的就地滤棒加工区数采和监控系统。自主开发OPC服务器,实现了滤棒成型主、辅... 针对滤棒成型作业区分散、设备种类多、制造厂家和数量多、接口协议复杂且不统一以及海量数据变量难识别等问题,设计并开发了基于OPC UA架构和实时内存数据库的就地滤棒加工区数采和监控系统。自主开发OPC服务器,实现了滤棒成型主、辅设备的实时数据采集,并通过高效内存数据库服务器对生产及设备信息进行海量存储,进而实现了对滤棒成型车间生产过程信息的全面、准确迁移集成,以及对滤棒生产、产量、质量、机台效率、设备状态等信息的可视化区域集控。 展开更多
关键词 滤棒成型加工 区域集控 OPC UA 实时内存数据库
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火焰相对面积估算方法的研究及实现
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作者 林晓燕 邱天 +2 位作者 张昕 吴建邦 宁洪龙 《电子设计工程》 2024年第3期190-195,共6页
为配合自动灭火装置的喷水定位,研究并实现了一种基于双目相机的火焰相对面积估算方法。通过YOLOv5s检测火焰并利用双目摄像头获得火焰区域的深度,根据火焰深度与火焰像素占比估算得到火焰相对面积。基于该方法得到的火焰深度误差小于1... 为配合自动灭火装置的喷水定位,研究并实现了一种基于双目相机的火焰相对面积估算方法。通过YOLOv5s检测火焰并利用双目摄像头获得火焰区域的深度,根据火焰深度与火焰像素占比估算得到火焰相对面积。基于该方法得到的火焰深度误差小于10%,估算的火焰相对面积平均误差为12.2%。所提方法在准确提取图像中火焰区域的同时可以较为准确地估算火焰面积,能够为室内火灾实时检测及灭火技术的发展提供一定参考。 展开更多
关键词 图像处理 火焰相对面积 双目测距 YOLOv5s
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基于机器学习的西南岩溶泉流量模拟研究
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作者 马从文 张志才 +3 位作者 陈喜 程勤波 彭韬 张林 《中国岩溶》 CAS CSCD 北大核心 2024年第1期48-56,共9页
岩溶泉对西南岩溶区生态系统稳定和经济社会发展具有重要意义。受岩溶区独特水文地质结构与多重水流过程控制,岩溶泉流量具有复杂的动态变化特征,机器学习模型为其模拟和预测提供了有效手段。然而,岩溶泉域降雨−泉流量过程及其时空变异... 岩溶泉对西南岩溶区生态系统稳定和经济社会发展具有重要意义。受岩溶区独特水文地质结构与多重水流过程控制,岩溶泉流量具有复杂的动态变化特征,机器学习模型为其模拟和预测提供了有效手段。然而,岩溶泉域降雨−泉流量过程及其时空变异特征对机器学习模型结构与模拟精度的影响仍不明晰。本文选取西南典型岩溶泉,基于长短期记忆网络(LSTM)建立岩溶泉流量模拟模型,利用泉域实测逐小时降雨与泉流量序列进行模型训练与验证。在此基础上,分析了不同降雨−泉流量过程对岩溶泉流量模拟精度的影响,以及岩溶水文地质结构对降雨−泉流量响应滞时的控制作用。研究结果显示,山坡岩溶泉与流域出口岩溶泉训练期纳什效率系数(NSE)分别为0.942与0.951,验证期分别为0.831与0.834。对于山坡岩溶泉与流域出口岩溶泉,利用全年实测序列训练的模型预测雨季泉流量存在较大偏差,NSE分别为0.793与0.798,而利用雨季实测序列训练的模型预测雨季泉流量,精度显著提升,NSE分别为0.956与0.962,且此差异在暴雨频繁的5、6、7月尤为显著。受浅薄土壤与表层岩溶带分布影响,山坡岩溶泉LSTM模型时序步长显著小于流域出口岩溶泉。 展开更多
关键词 机器学习 LSTM 岩溶泉流量 响应滞时 岩溶降雨−泉流量过程
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