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进展期胃癌胃壁浸润CT“分层征”的病理学基础 被引量:17
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作者 陈棣华 张洁 +1 位作者 蒋光愉 陈金城 《中国医学影像技术》 CSCD 2001年第9期905-907,共3页
目的 探讨进展期胃癌胃壁浸润CT分层征象的病理学基础。方法  31例病理证实的进展期胃癌 ,均作了胃肠造影及螺旋CT扫描。术后胃标本牵拉固定后 ,放射状象限取材 ,作病理对照观察。结果 动脉期、非平衡期及平衡期可见病灶分层情况分别... 目的 探讨进展期胃癌胃壁浸润CT分层征象的病理学基础。方法  31例病理证实的进展期胃癌 ,均作了胃肠造影及螺旋CT扫描。术后胃标本牵拉固定后 ,放射状象限取材 ,作病理对照观察。结果 动脉期、非平衡期及平衡期可见病灶分层情况分别为 35 .5 %、19.4%及 12 .9%。①病灶分两层 ,其低密带清晰 ,密度均一者有 11例 ,系黏膜下层癌细胞浸润及纤维组织广泛增生 ,使黏膜下层致密、增厚 ,肌层结构完整 ,仅在肌束间有癌巢形成。②病灶虽分两层 ,但其低密带不均 ,内可见条索影者 7例 ,为黏膜下层坏死、肿瘤细胞分泌的黏液及少量纤维组织增生构成。③病灶分三层者 2例 ,分四层者 1例 ,CT表现为“靶征” ,是癌组织树根状从黏膜下层浸润至肌层的肌纤维束之间所致。结论 进展期胃癌螺旋CT三期扫描可清楚地观察病灶分层 ,与病理对照 。 展开更多
关键词 进展期胃癌 浸润 分层征 病理学基础 螺旋CT
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驻波场中非均匀手征分层粒子的辐射力特性
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作者 白靖 马文浩 +2 位作者 葛城显 吴振森 许彤 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第18期145-161,共17页
随着光学技术的发展,人们对光场与微粒相互作用的研究越来越深入.通过研究驻波场中非均匀手性粒子的辐射力特性,可以深入了解光场对微粒的影响机制,为微纳米尺度下分层手征粒子的操控和应用提供新思路.本文对双高斯波束照射下非均匀手... 随着光学技术的发展,人们对光场与微粒相互作用的研究越来越深入.通过研究驻波场中非均匀手性粒子的辐射力特性,可以深入了解光场对微粒的影响机制,为微纳米尺度下分层手征粒子的操控和应用提供新思路.本文对双高斯波束照射下非均匀手征分层粒子的辐射力展开研究.从广义洛伦兹-米氏理论(generalized Lorentz-Mie theory,GLMT)和球矢量波函数(spherical vector wave functions,SVWFs)出发,推导了双高斯波束(double Gaussian beams,DGBS)的总入射场展开系数.基于边界连续条件和电磁动量守恒定理,得到双高斯波对粒子的辐射力表达式.通过与现有文献进行比较,证明了理论和程序的正确性.详细分析了各种参数对辐射力的影响,如束腰宽度、偏振形式、粒子半径、内外手征参数、折射率、最外层厚度等.研究表明,与单个高斯束相比,反向传播的高斯驻波在捕获或限制非均匀手性分层粒子方面表现出显著优势,提供了更强的粒子操控能力.此外,通过选择合适的偏振态入射,可以在这些参数之间实现微妙的平衡,从而有效地稳定俘获非均匀手性粒子.这些研究对于分析和理解形状复杂多层生物细胞的光学特性具有重要意义,并在多层生物结构微操控方面具有重要应用价值. 展开更多
关键词 双高斯波束 辐射力 非均匀手分层粒子
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分层有耗手征介质中斜入射电磁波的传播矩阵 被引量:5
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作者 王飞 魏兵 《物理学报》 SCIE EI CAS CSCD 北大核心 2017年第6期78-87,共10页
根据相位匹配条件,推导了平面电磁波斜入射情形下分层有耗手征介质中本征波复数波矢量的实部和虚部,二者方向不同使得在介质中传播的本征波为非均匀平面波.然后通过波矢量实部确定了介质中本征波的折射角.最后根据边界条件和本征波场方... 根据相位匹配条件,推导了平面电磁波斜入射情形下分层有耗手征介质中本征波复数波矢量的实部和虚部,二者方向不同使得在介质中传播的本征波为非均匀平面波.然后通过波矢量实部确定了介质中本征波的折射角.最后根据边界条件和本征波场方程给出了分层有耗手征介质中斜入射电磁波的传播矩阵,该传播矩阵可用于解析分析任意入射角情形下分层手征介质的反射透射和电波传播特性. 展开更多
关键词 分层有耗手介质 斜入射 传播矩阵
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椭圆波束对非均匀手征分层粒子的俘获特性研究
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作者 白靖 葛城显 +2 位作者 何浪 刘轩 吴振森 《物理学报》 SCIE EI CAS CSCD 北大核心 2022年第10期152-164,共13页
非均匀手征分层粒子的俘获特性研究在化学工程、生物医药、光镊、微纳米加工等领域都有着重要的应用.为了有效地俘获及操控手征分层球形粒子,本文对椭圆高斯波束照射下手征分层球形粒子的辐射俘获力展开研究.从广义米理论出发,将入射椭... 非均匀手征分层粒子的俘获特性研究在化学工程、生物医药、光镊、微纳米加工等领域都有着重要的应用.为了有效地俘获及操控手征分层球形粒子,本文对椭圆高斯波束照射下手征分层球形粒子的辐射俘获力展开研究.从广义米理论出发,将入射椭圆高斯波束用矢量球谐函数展开,根据波束散射理论及电磁场动量守恒定理,得出椭圆高斯波束对手征分层球形粒子辐射俘获力的级数表达式,并对椭圆高斯波束入射分层手征细胞时的轴向及横向俘获力进行了数值模拟,讨论了手征参数、极化状态、束腰宽度、损耗以及最外层厚度对俘获情况的影响.研究表明:手征参数的引入会降低非均匀手征粒子的轴向俘获特性,但是选择合适的极化态入射时,可以有效地实现对非均匀手征粒子的稳定俘获.对于内层损耗小的手征多层球形粒子,当内层折射率大于最外层时,最外层厚度大的非均匀手征粒子在光轴上更容易俘获;反之内层折射率小于最外层时,最外层厚度小的粒子在光轴上有更强的束缚;同时与传统圆高斯波束相比,椭圆高斯波束的强会聚性更容易实现对非均匀手征分层细胞的三维俘获,具有良好的应用前景. 展开更多
关键词 辐射俘获力 椭圆波束 分层细胞 光镊
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A Feature Definition Hierarchy for Supporting Design Process
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作者 孙正兴 张福炎 蔡士杰 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期55-62,共8页
The adaptability of features definition to applications is an essential condition for implementing feature based design. This paper makes attempt to present a hierarchical definition structure of features. The propos... The adaptability of features definition to applications is an essential condition for implementing feature based design. This paper makes attempt to present a hierarchical definition structure of features. The proposed scheme divides feature definition into application level, form level and geometric level, and provides links between different levels with feature semantics interpretation and enhanced geometric face adjacent graph. respectively. The results not only enable feature definition to abate from the specific dependence and become more extensive, but also provide a theoretical foundation for establishing the concurrent feature based design process model. 展开更多
关键词 design process feature based modeling feature definition hierarchical construction
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Pre-stack-texture-based reservoir characteristics and seismic facies analysis 被引量:3
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作者 宋承云 刘致宁 +2 位作者 蔡涵鹏 钱峰 胡光岷 《Applied Geophysics》 SCIE CSCD 2016年第1期69-79,219,共12页
Seismic texture attributes are closely related to seismic facies and reservoir characteristics and are thus widely used in seismic data interpretation.However,information is mislaid in the stacking process when tradit... Seismic texture attributes are closely related to seismic facies and reservoir characteristics and are thus widely used in seismic data interpretation.However,information is mislaid in the stacking process when traditional texture attributes are extracted from poststack data,which is detrimental to complex reservoir description.In this study,pre-stack texture attributes are introduced,these attributes can not only capable of precisely depicting the lateral continuity of waveforms between different reflection points but also reflect amplitude versus offset,anisotropy,and heterogeneity in the medium.Due to its strong ability to represent stratigraphies,a pre-stack-data-based seismic facies analysis method is proposed using the selforganizing map algorithm.This method is tested on wide azimuth seismic data from China,and the advantages of pre-stack texture attributes in the description of stratum lateral changes are verified,in addition to the method's ability to reveal anisotropy and heterogeneity characteristics.The pre-stack texture classification results effectively distinguish different seismic reflection patterns,thereby providing reliable evidence for use in seismic facies analysis. 展开更多
关键词 Pre-stack texture attributes reservoir characteristic seismic facies analysis SOM clustering gray level co-occurrence matrix
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Neighborhood fusion-based hierarchical parallel feature pyramid network for object detection 被引量:3
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作者 Mo Lingfei Hu Shuming 《Journal of Southeast University(English Edition)》 EI CAS 2020年第3期252-263,共12页
In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid... In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid network(FPN)and deconvolutional single shot detector(DSSD),where the bottom layer of the feature pyramid network relies on the top layer,NFPN builds the feature pyramid network with no connections between the upper and lower layers.That is,it only fuses shallow features on similar scales.NFPN is highly portable and can be embedded in many models to further boost performance.Extensive experiments on PASCAL VOC 2007,2012,and COCO datasets demonstrate that the NFPN-based SSD without intricate tricks can exceed the DSSD model in terms of detection accuracy and inference speed,especially for small objects,e.g.,4%to 5%higher mAP(mean average precision)than SSD,and 2%to 3%higher mAP than DSSD.On VOC 2007 test set,the NFPN-based SSD with 300×300 input reaches 79.4%mAP at 34.6 frame/s,and the mAP can raise to 82.9%after using the multi-scale testing strategy. 展开更多
关键词 computer vision deep convolutional neural network object detection hierarchical parallel feature pyramid network multi-scale feature fusion
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Dynamic distribution and stem cell characteristics of Sox1-expressing cells in the cerebellar cortex 被引量:1
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作者 Joelle Alcock Virginie Sottile 《Cell Research》 SCIE CAS CSCD 2009年第12期1324-1333,共10页
Bergmann glia cells are a discrete radial glia population surrounding Purkinje cells in the cerebellar cortex. Although Bergmann glia are essential for the development and correct arborization of Purkinje cells, littl... Bergmann glia cells are a discrete radial glia population surrounding Purkinje cells in the cerebellar cortex. Although Bergmann glia are essential for the development and correct arborization of Purkinje cells, little is known about the regulation of this cell population after the developmental phase. In an effort to characterize this population at the molecular level, we have analyzed marker expression and established that adult Bergmann glia express Soxl, Sox2 and Sox9, a feature otherwise associated with neural stem cells (NSCs). In the present study, we have further analyzed the developmental pattern of Soxl-expressing cells in the developing cerebellum. We report that before becoming restricted to the Purkinje cell layer, Soxl-positive cells are present throughout the immature tissue, and that these cells show characteristics of Bergmann glia progenitors. Our study shows that these progenitors express Soxl, Sox2 and Sox9, a signature maintained throughout cerebellar maturation into adulthood. When isolated in culture, the Soxl-expressing cerebellar population exhibited neurosphere-forming ability, NSC-marker characteristics, and demonstrated multipotency at the clonal level. Our results show that the Bergmann glia population expresses Soxl during cerebellar development, and that these cells can be isolated and show stem cell characteristics in vitro, suggesting that they could hold a broader potential than previously thought. 展开更多
关键词 CEREBELLUM Sox genes stem cell
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Paleogeomorphy,provenance system and sedimentary system of the Dongying formation in the Qikou sag 被引量:5
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作者 WANG Hua HUANG Chuan-yan +6 位作者 ZHAO Shu-e YAN De-tian BAI Yun-feng XIANG Xue-mei CHEN Si XIA Cun-yin LIAO Ji-hua 《Mining Science and Technology》 EI CAS 2009年第6期800-806,共7页
Reconstructed synsedimentary paleogeomorpholgy is an effective method in predicting the distribution of sandbodies and can provide valid evidence in the search for reservoirs. Based on a synsedimentary paleogeomorphol... Reconstructed synsedimentary paleogeomorpholgy is an effective method in predicting the distribution of sandbodies and can provide valid evidence in the search for reservoirs. Based on a synsedimentary paleogeomorpholgy reconstruction of the third member of the Dongying formation (Ed3) in the Qikou sag,the basic paleogeomorphic characteristics of Ed3 are described and the spatial distributions of denudation and subsidence areas are discussed. Key boundary faults controlling the deposition of important sediment bodies are proposed and the interrelations among faulted slope-break belts or flexure belts,intra-depression uplifts and sags,sediment sources and sediments input points have been investigated. 展开更多
关键词 paleogeomorphology provenance system sedimentary system Dongying formation Qikou sag
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Reservoir characteristics of Donghe well No.1 in Tarim Basin 被引量:1
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作者 Liao Taiping Hu Jingjing +1 位作者 Lai Fuqiang Duan Yonggang 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期719-724,共6页
Based on the techniques of X-ray diffraction analysis, identification of the thin sections of core cast, phys- ical analysis and scanning electron microscopy analysis, this paper studied the reservoir characteristics ... Based on the techniques of X-ray diffraction analysis, identification of the thin sections of core cast, phys- ical analysis and scanning electron microscopy analysis, this paper studied the reservoir characteristics of the Carboniferous strata in Donghe well No.1 of Tarim region. The results show that the reservoir lithology is mainly the fine-grained quartz sandstone with ferrocalcite and pyrite, mud cement-based, the permeability concentrated in 5-40 × 10-3 μm2, a small part of the high permeability up to 150-327 ×10-3 μm2 and porosity ranged from 10% to 20%. The most part of the reservoirs is low perme- ability with a small part of the layer in moderate-high permeability. The types of reservoir space include intergranular pores, intra particle-molding pores, micro-pores and cracks, which mainly are intergranular pores with the pore diameter of 15-200 μm, 95.5μm on average. And the types of the throats are comolex with the main tvne of constricted l:hroats in this area and large contribution to the permeability. 展开更多
关键词 Tarim Basin Carboniferous system Sandstone reservoir Physical characteristics Features of pore throats
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Gustiness and coherent structure under weak wind period in atmospheric boundary layer 被引量:2
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作者 Li Qi-Long Cheng Xue-Ling Zeng Qing-Cun 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第1期52-59,共8页
Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-th... Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-thermometers at 47 m,120 m,and 280 m levels on Beijing 325 m meteorological tower.The time series of 3D atmospheric velocity were analyzed by using conventional Fourier spectral analysis and decompose into three parts:basic mean flow(period > 10 min),gusty disturbances(1 min < period < 10 min)and turbulence fluctuations(period < 1 min).The results show that under weak mean wind condition:1)the gusty disturbances are the most strong fluctuations,contribute about 60% kinetic energy of eddy kinetic energy and 80% downward flux of momentum,although both the eddy kinetic energy and momentum transport are small in comparison with those in strong mean wind condition;2)the gusty wind disturbances are anisotropic;3)the gusty wind disturbances have obviously coherent structure,and their horizontal and vertical component are negatively correlated and make downward transport of momentum more effectively;4)the friction velocities related to turbulence and gusty wind are approximately constant with height in the surface layer. 展开更多
关键词 Atmospheric boundary layer gusty wind coherent structure weak wind downward flux of momentum
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Analysis of geological conditions and thermal reservoir characteristics of Guantao Formation in new coastal region 被引量:1
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作者 JIANG Guosheng HUANG Xianlong +3 位作者 HU Liangjun ZHANG Liandi LIU Zan LU Bao 《Global Geology》 2013年第4期201-206,共6页
Geothermal resources is one of the most practical and competitive new energy at present,and there is abundant geothermal resources in the new coastal region.The article get the three following conclusion through the g... Geothermal resources is one of the most practical and competitive new energy at present,and there is abundant geothermal resources in the new coastal region.The article get the three following conclusion through the geothermal geological condition by the drilling strata and the condition of the reducing test:stratigraphic division is done by the analysis of formation lithology and the drilling aging;the water yield is higher than 100m3/h,the flow temperature is 67℃--71℃;the average geothermal gradient of the overlying strata is 3.08℃--3.33℃/100 m. 展开更多
关键词 the new coastal region geothermal well Guantao Formation drilling time aging
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Multifractal Characteristics of Intermittent Turbulence in the Urban Canopy Layer 被引量:1
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作者 XU Jing-Jing HU Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第2期72-77,共6页
The multifractality of energy and thermal dissipation of fully developed intermittent turbulence is investigated in the urban canopy layer under unstable conditions by the singularity spectrum for the fractal dimensio... The multifractality of energy and thermal dissipation of fully developed intermittent turbulence is investigated in the urban canopy layer under unstable conditions by the singularity spectrum for the fractal dimensions of sets of singularities characterizing multifractals. In order to obtain high-order moment properties of smallscale turbulent dissipation in the inertial range, an ultrasonic anemometer with a high sampling frequency of 100 Hz was used. The authors found that the turbulent signal could be singular everywhere. Moreover, the singular exponents of energy and thermal dissipation rates are most frequently encountered at around 0.2, which is significantly smaller than the singular exponents for a wind tunnel at a moderate Reynolds number. The evidence indicates a higher intermittency of turbulence in the urban canopy layer at a high Reynolds number, which is demonstrated by the data with high temporal resolution. Furthermore, the temperature field is more intermittent than the velocity field. In addition, a large amount of samples could be used for verification of the results. 展开更多
关键词 urban canopy layer intermittent turbulence turbulent dissipation MULTIFRACTALITY singularity spectrum
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Horror Video Recognition Based on Fuzzy Comprehensive Evolution 被引量:2
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作者 SONG Wei YANG Pei +3 位作者 YANG Guosheng MA ChuanLian YU Jing LIMing 《China Communications》 SCIE CSCD 2014年第A02期86-94,共9页
Technique for horror video recognition is important for its application in web content filtering and surveillance, especially for preventing children from being threaten. In this paper, a novel horror video recognitio... Technique for horror video recognition is important for its application in web content filtering and surveillance, especially for preventing children from being threaten. In this paper, a novel horror video recognition algorithm based on fuzzy comprehensive evolution model is proposed. Three low-level video features are extracted as typical features, and they are video key-light, video colour energy and video rhythm. Analytic Hierarchy Process (AHP) is adopted to estimate the weights of extracted features in fuzzy evolution model. Horror evaluation (membership function) is on shot scale and it is constructed based on the knowledge that videos which share the same affective have similar low-level features. K-Means algorithm is implemented to help finding the most representative feature vectors. The experimental results demonstrate that the proposed approach has good performance in recognition precision, recall rate and F1 measure. 展开更多
关键词 horror video recognition videoaffective fuzzy comprehensive evolution K-Meanscluster
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Fractal characterization for the mining crack evolution process of overlying strata based on microseismic monitoring technology 被引量:4
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作者 Liu Chao Xue Junhu +1 位作者 Yu Guofeng Cheng Xiaoyu 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第2期295-299,共5页
In order to study the evolution laws during the development process of the coal face overburden rock mining-induced fissure,we studied the process of evolution of overburden rock mining-induced fissures and dynamicall... In order to study the evolution laws during the development process of the coal face overburden rock mining-induced fissure,we studied the process of evolution of overburden rock mining-induced fissures and dynamically quantitatively described its fractal laws,based on the high-precision microseismic monitoring method and the nonlinear Fractal Geometry Theory.The results show that:the overburden rock mining-induced fissure fractal dimension experiences two periodic change processes with the coal face advance,namely a Small→ Big→ Small process,which tends to be stable;the functional relationship between the extraction step distance and the overburden rock mining-induced fissure fractal dimension is a cubic curve.The results suggest that the fractal dimension reflects the evolution characteristics of the overburden rock mining-induced fissure,which can be used as an evaluation index of the stability of the overburden rock strata,and it provides theoretical guidance for stability analysis of the overburden rock strata,goaf roof control and the support movements in the mining face. 展开更多
关键词 Microseismic monitoring technology Fractal characterization Mining crack Evolution law Overlying strata
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Optimum mining method selection using fuzzy analytical hierarchy process–Qapiliq salt mine,Iran 被引量:7
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作者 Karimnia Hamed Bagloo Heydar 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期225-230,共6页
Mining method selection is the first and the most critical problem in mine design and depends on some parameters such as geotechnical and geological features and economic and geographic factors. In this paper, the fac... Mining method selection is the first and the most critical problem in mine design and depends on some parameters such as geotechnical and geological features and economic and geographic factors. In this paper, the factors affecting mining method selection are determined. These factors include shape, thick- ness, depth, slope, RMR and RSS of the orebody, RMR and RSS of the hanging wall and footwall. Then, the priorities of these factors are calculated. In order to calculate the priorities of factors and select the best mining method for Qapiliq salt mine, Iran, based on these priorities, fuzzy analytical hierarchy process (AHP) technique is used. For this purpose, a questionnaire was prepared and was given to the associated experts. Finally, after a comparison carried out based on the effective factors, between the four mining methods including area mining, room and pillar, cut and fill and stope and pillar methods, the stope and nillar mining method was selected as the most suitable method to this mine. 展开更多
关键词 Mining method selection Fuzzy AHP Multiple criteria decision making Salt mine
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Reservoir lithology stochastic simulation based on Markov random fields 被引量:2
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作者 梁玉汝 王志忠 郭建华 《Journal of Central South University》 SCIE EI CAS 2014年第9期3610-3616,共7页
Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass re... Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass relationships. While, many relative studies were based on Markov chain, not MRF, and using Markov chain model for 3D reservoir stochastic simulation has always been the difficulty in reservoir stochastic simulation. MRF was proposed to simulate type variables(for example lithofacies) in this work. Firstly, a Gibbs distribution was proposed to characterize reservoir heterogeneity for building 3-D(three-dimensional) MRF. Secondly, maximum likelihood approaches of model parameters on well data and training image were considered. Compared with the simulation results of MC(Markov chain), the MRF can better reflect the spatial distribution characteristics of sand body. 展开更多
关键词 stochastic modeling Markov random fields training image Monte Carlo simulation
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Emission Characteristics of Volatile Organic Compounds from Automobile Coating Industry in Chongqing City
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作者 Zhou Zhi'en Fang Weikai +2 位作者 Luo Qian Wang Xiaochen Wu Liping 《Journal of Environmental Science and Engineering(B)》 2017年第11期543-552,共10页
To fully analyze emission characteristics of VOCs (Volatile Organic Compounds) from automobile coating industry in Chongqing city, related enterprises in the city were investigated in detail. The results show that t... To fully analyze emission characteristics of VOCs (Volatile Organic Compounds) from automobile coating industry in Chongqing city, related enterprises in the city were investigated in detail. The results show that the emission of VOCs from the automobile industry in Chongqing city was approximately 20,000 t in 2012, and the contribution rate of automobile coating was 83%. Most VOCs discharged from automobile coating industry were mainly from the use of coatings, diluents, curing agents and other materials containing VOCs. During the process of automobile coating, VOCs were mainly produced during the processes of spraying and drying. Besides, VOCs are partly produced during the processes of mixing paint, gluing, waxing and repairing. The major ingredients of VOCs discharged during the process of automobile coating were methylbenzene, dimethylbenzene, trimethylbenzene, cumene, ethyl acetate, butyl alcohol, n-butyl alcohol, isobutyl alcohol, formaldehyde, butanone, acetone, cyclohexanone and methyl ethyl ketone. Besides, the ingredients of naphtha and aromatic hydrocarbon in VOCs need to be determined. The maximum OFP (Ozone Formation Potential) of the above pollutants by the typical enterprises was 900-1,300 mg/m^3. The production of SOA (Secondary Organic Aerosol) was 3,636-11,073 t/a, which didn’t include the contribution of aldehydes, ketones, ethers and esters to SOA. This research could provide scientific reference for the establishment of emission standard, control technology and management methods of VOCs from automobile coating industry that accord with economic and social development in Chongqing city. 展开更多
关键词 Automobile coating VOCs environmental impact OZONE SOA.
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Study on the base-level cycle and the sedimentology of Permian in Jiyang area
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作者 LI Zeng-xue HAN Mei-lian +1 位作者 SONG Ming-shui LU Da-wei 《Journal of Coal Science & Engineering(China)》 2009年第1期7-15,共9页
The identification of sequence boundaries is the key point for sequence stratigraphic classification. Both the higher-order sequences and the units within the sequences are bounded with the key sediments or isochronou... The identification of sequence boundaries is the key point for sequence stratigraphic classification. Both the higher-order sequences and the units within the sequences are bounded with the key sediments or isochronous surfaces. Eight sequences can be divided in the whole Permo-Carboniferous strata (the Shiqianfeng Formation is not included), which is from the Benxi Formation, Taiyuan Formation, Shanxi Formation, Xiashihezi Formation, Wanshan Section, and Kuishan Section to the Xiaofuhe Section. Also, different system tracts (Iowstand system tract, transgression system tract and highstand system tract) and some parasequences can be recognized in each sequence. Parasequence analysis was on the basis of the division of the base-level cycle. The base-level cycle was mainly identified according to the change of the water area, which was reflected by the depositional sequence. The physical characteristic of the strata was reflected by the well log. It was supplied by the test of the minerals and rocks and the analysis of the micro-element in the lab. The paleogeographic characteristic of the Iowstand system tract in the sequence Ⅵ is that the east-north part takes the river system as its feature; the south part is the lake system, the river channel spreads from north to south, and the area of the flooding plain is great. The paleogeographic characteristic of the water-transgressive system tract is that the range of the lake in the south extended distinctively, the range of the river channel in the east reduced. The coastal shallow lake deposit is the main characteristic in the water-transgressive system tract. The paleogeographic characteristic of the highstand system tract is similar to the one of the Iowstand system tract. 展开更多
关键词 Jiyang area base-level PARASEQUENCE the reservoir of the coal-derived gas
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Characterization of Placic Horizons in Ironstone Soils of Louisiana, USA
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作者 D. C. WEINDORF N. BAKR +3 位作者 Y. ZHU B. HAGGARD S. JOHNSON J. DAIGLE 《Pedosphere》 SCIE CAS CSCD 2010年第4期409-418,共10页
Placic horizons, defined as thin, wavy, hardened layers of iron and organic matter, are rare within the United States, occurring only in Washington, Alaska, and Hawaii. While ironstone is common in many soils of the s... Placic horizons, defined as thin, wavy, hardened layers of iron and organic matter, are rare within the United States, occurring only in Washington, Alaska, and Hawaii. While ironstone is common in many soils of the southeastern United States, it is not known to contain appreciable organic matter. As a pilot study evaluating the justification for a larger study on ironstone in Louisiana, a 40 m lateral exposure with suspected placic horizons was evaluated in Vernon Parish, Louisiana. Results of laboratory analysis show elevated levels of iron and organic matter in the suspect horizons that meet the criteria of placic horizons as defined by the Soil Survey Staff. Based on the results of this study, additional evaluation of multiple pedons with similar features is warranted. Should additional pedons demonstrate similar properties, a new great group of 'Petrudepts' would be needed to describe both the placic horizons in the pedon and the udic moisture regime in which they occur. 展开更多
关键词 ortstein pedon petroferric contact Petrudepts
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