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基于半监督学习的糖尿病视网膜病变自动评级和分割

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建模与仿真 2024年第3期13卷 3828-3841页

作者：居逸文上海理工大学光电信息与计算机工程学院上海

糖尿病视网膜病变(DR)是导致永久性失明的主要原因之一,尤其是在中老年人中。早期发现DR对于预防视力丧失至关重要。疾病严重程度分级可以看作是一个分类问题,只需要图像级的标注,而病变分割则需要更强的像素级标注。然而逐像素数据标... 详细信息

糖尿病视网膜病变(DR)是导致永久性失明的主要原因之一,尤其是在中老年人中。早期发现DR对于预防视力丧失至关重要。疾病严重程度分级可以看作是一个分类问题,只需要图像级的标注,而病变分割则需要更强的像素级标注。然而逐像素数据标注非常耗时,需要专家。本文提出了一种协同学习的方法来联结优化DR评级和病灶检测。首先利于小部分逐像素数据标注数据训练一个多病变标签语义分割模型,接着基于最初对大量图像级注释数据预测的病变图,设计了一个疾病注意力评级模型。同时,疾病注意力模型可以利用特定类的信息对病灶图进行细化,以半监督的方式对分割模型进行微调。生成对抗性架构也被应用在训练过程中。接着在三个公共数据集上对本文的方法进行验证,并与一些先进的模型进行对比,取得较好的性能。

关键词：糖尿病视网膜病变评级分割生成对抗半监督疾病注意力

Human Health Risk Assessment Model of Organic Pollution in Groundwater:Shijiazhuang Industrial Zone

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1508-1517页

作者： YANG Mei FEI Yuhong ju yiwen LI Huaqi Key Laboratory of Computational Geodynamics of Chinese Academy of Sciences College of Earth Science Graduate University of Chinese Academy Sciences Beijing 100049 China The Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences （CAGS） Shijiazhuang 050061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 10003 7 China

In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds （VOC） after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that：（1） Compared with these permissible level standards in China （GB 3838-2002） and National Primary Drinking Water Regulations of the United States, the residents＇ daily life had not been affected by the groundwater in this area （except for relative bad water quality of HB3-4 and HB3-6）; （2） The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; （3） As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; （4） Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents＇ in study areas; （5） In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was： drinking water pathway 〉 dermal contact pathway.

关键词： groundwater pollution organic contaminants residual rate assessment model human health risk

Response of Macromolecular Structure to Deformation in Tectonically Deformed Coal

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 82-90页

作者： LI Xiaoshi ju yiwen HOU Quanlin FAN junjia Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences PetroChina Research Institute of Petroleum Exploration and Development Key Laboratory of Basin Structure and Petroleum Accumulation

The structural evolution of tectonically deformed coals （TDC） with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction （XRD） analysis on 31 samples of different metamorphic grades （R ： 0.7%-3.1%） collected from the Huaibei coalfield. The results indicated that there are different evolution characteristics between the ductile and brittle deformational coals with increasing of metamorphism and deformation. On the one hand, with the increase of metamorphism, the atomic plane spacing （d002） is decreasing at step velocity, the stacking of the BSU layer （Lc） is increasing at first and then decreasing, but the extension of the BSU layer （La） and the ratio of La/Lc are decreasing initially and then increasing. On the other hand, for the brittle deformational coal, d002 is increasing initially and then decreasing, which causes an inversion of the variation of Lc and La under the lower-middle or higher-middle metamorphism grade when the deformational intensity was increasing. In contrast, in the ductile deformational coals, d002 decreased initially and then increased, and the value of L~ decreased with the increase of deformational intensity. But the value of La increased under the lower-middle metamorphism grade and increased at first and then decreased under the higher-middle metamorphism grade. We conclude that the degradation and polycondensation of TDC macromolecular structure can be obviously impacted during the ductile deformational process, because the increase and accumulation of unit dislocation perhaps transforms the stress into strain energy. Meanwhile, the brittle deformation can transform the stress into frictional heat energy, and promote the metamorphism and degradation as well. It can be concluded that deformation is more important than metamorphism to the differential evolution of the ductile and brittle deformational coals.

关键词： tectonically deformed coal X-ray diffraction deformational mechanism deformationalintensity macromolecular structure

Fracability Evaluation of Shale of the Wufeng-Longmaxi Formation in the Changning Area, Sichuan Basin

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 996-1004页

作者： HUANG Cheng XU Tianyang ju yiwen ZHU Hongjian ju Liting LI Wuyang Key Laboratory of Computational Geodynamics Chinese Academy of SciencesCollege of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

The fracturing technology for shale gas reservoir is the key to the development of shale gas *** makes much sense to study the mechanical properties and deformation characteristics of shale,due to its close relationship with the fracability of shale gas *** paper took marine shale in the Changning area,southern Sichuan Basin of China as the research *** on field profile and hand specimen observation,we analyzed the development of natural fractures and collected samples from Wufeng Formation and Longmaxi *** with the indoor experiment,we investigated the macroscopic and microscopic structural features and the remarkable heterogeneity of shale *** we illustrated the mechanics and deformation characteristics of shale,through uniaxial compression test and direct shear *** shale has two types of fracture modes,which depend on the angular relation between loading direction and the bedding ***,the Wufeng shale has a higher value of brittleness index than the Longmaxi shale,which was calculated using two methods,mechanical parameters and mineral *** the above results,we proposed a fracability evaluation model for shale gas reservoir using the analytic hierarchy *** influence factors,brittleness index,fracture toughness,natural fractures and cohesive force,are ***,under the control of normalized value and weight coefficient of each influence factor,the calculations results indicate that the fracability index of the Wufeng Formation is higher than that of the Longmaxi Formation in Changning area,southern Sichuan Basin.

关键词： marine shale mechanical properties fracability evaluation analytic hierarchy process Sichuan Basin

Relationship between nano-scale deformation of coal structure and metamorphic-deformed environments

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Chinese Science Bulletin 2005年第16期50卷 1784-1795页

作者： ju yiwen JIANG Bo HOU Quanlin WANG Guiliang College of Mineral Resource and Geosciences China University of Mining and Technology Xuzhou 221008 China Laboratory of Computational Geodynamics College of Geosciences Graduate University of Chinese Academy of Sciences Beijing 100049. China

There is a more consanguineous relation be-tween nano-scale deformation of coal structure and meta-morphic-deformed environment. In different metamor-phic-deformed environments, deformation in the coal struc-ture can occur not only at micro-scale, but also at nano-scale, and even leads to the change of molecular structure and nano-scale pore (<100 nm) structure. The latter is the main space absorbing coalbed methane. Through X-ray diffraction (XRD) and liquid–nitrogen absorption methods, the charac-teristics of macromolecular and nano-scale pore structures of coals in different metamorphic-deformed environments and deformational series of coals have been studied. By combin-ing with high-resolution transmission electron microcopy (HRTEM), the macromolecular and nano-scale pore struc-tures are also directly observed. These results demonstrate that the stacking Lc of the macromolecular BSU in tectonic coals increases quickly from the metamorphic-deformed environment of low rank coals to that of high rank coals. For different deformed tectonic coals, in the same metamor-phic-deformed environment, the difference of Lc is obvious. These changes reflect chiefly the difference of different tem-perature and stress effect of nano-scale deformation in tec-tonic coals. The factor of temperature plays a greater role in the increase of macromolecular structure parameters Lc, the influence of stress factor is also important. With the stress strengthening, Lc shows an increasing trend, and La /Lc shows a decreasing trend. Therefore, Lc and La /Lc can be used as the indicator of nano-scale deformation degree of tectonic coals. With increasing temperature and pressure, especially oriented stress, the orientation of molecular structure be-comes stronger, and ordering degree of C-nets and the ar-rangement of BSU are obviously enhanced. For the deforma-tion of nano-scale pore structure, in the same metamor-phic-deformed environment, along with the strengthening of stress, the ratio of m

关键词：煤结构纳米变形大分子结构地质环境

Improved geologic surface approximation using a multiquadric method with additional constraints

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Mining Science and Technology 2010年第4期20卷 600-606页

作者： SONG Xianfeng RUI Xiaoping ju yiwen YANG Yongguo Laboratory of Computing Geodynamics Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Resource and Geoscience China University of Mining & Technology Xuzhou 221116 China

Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when reconstructing a surface. This paper presents an improved geologic surface approximation method using a multiquadric function and borehole data. Additional information, i.e., inequality elevation and dip-strikes data extracted from outcrops or mining faces, is introduced in the form of physical constraints that control local changes in the estimated surface. Commonly accepted hypothesis states that geologic surfaces can be approximated to any desired degree of exactness by the summation of regular, mathematically defined, surfaces: in particular displaced quadric forms. The coefficients of the multiquadric functions are traditionally found by a least squares method. The addition of physical constraints in this work makes such an approach into a non-deterministic polynomial time problem. Hence we propose an objective function that represents the quality of the estimated surface and that includes the additional constraints by incorporation of a penalty function. Maximizing the smoothness of the estimated surface and its fitness to the additional constraints then allows the coefficients of the multiquadric function to be obtained by iterative methods. This method was implemented and demonstrated using data collected from the 81'st coal mining area of the Huaibei Coal Group.

关键词： geologic surface spatial interpolation multiquadric function exterior penalty function physical constraints

An improved method of rendering oil extraction contour under constrained conditions

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Mining Science and Technology 2011年第3期21卷 337-342页

作者： Rui Xiaoping Song Xianfeng Yang Yongguo ju yiwen Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Resource and Geoscience China University of Mining ＆ Technology Xuzhou 221116 China

Aiming at the issue of oil extraction data analysis and data display, this paper introduces an effective contour map rendering method considering constrained factors of the distribution of oil reservoir and geological conditions. The constraints such as faults, ridges, scarps and island areas are first classified into two categories of geometries, namely, polylines and polygons. Then, a Triangulated Irregular Network (TIN) is constructed based on the geo-locations of oil wells and further refined with local constraints of polylines and polygons. Finally, the intersections of line segments between a specified equivalent surface and the triangles in TIN are calculated and the contours are thus formed by connecting these intersection line segments. The approach is well demonstrated with the oil extraction data of Xinjiang oil field in China.

关键词： Contour mapConstrained conditionsTINInterpolationSmooth

Heat flow and its coalbed gas effects in the central-south area of the Huaibei coalfield, eastern China

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Science China Earth Sciences 2010年第5期53卷 672-682页

作者： TAN JingQiang ju yiwen ZHANG WenYong HOU QuanLin TAN YongJie College of Earth Science Graduate University of Chinese Academy of SciencesBeijing 100049China No.3 Exploration Party of Anhui Bureau of Coal Geology Suzhou 234000China Development and Research Center China Geological SurveyBeijing 100083China

Based on an analysis of the present geo-temperature field and the thermal conductivity (K) of 62 samples from the central-south area of the Huaibei coalfield in eastern China, we calculated the heat flow and plotted its distribution map. The results show that the average heat flow in the research area is about 60 mW/m2. It is different from other major energy basins in the North China Plate, but has close relationship with the regional geology and the deep geological setting. The heat flow is comparatively higher in the southeastern, central, and northwestern areas than in the northeastern and southwestern areas. The geo-temperature distribution map of the bottom interface of the Permian coal measure was drawn by calculating its embedding depth and geo-temperature gradients. Finally, the present gas generation condition of the Permian coal measure is discussed by associating with the temperature condition, the vitrinite reflectance (Ro), the metamorphism of coal and tectonic-burial evolution. The study indicates all present characters of the Permian coal measure, such as lower present temperature, higher Ro value, middle-high rank coals, and uplift and extension events after the coal measure sediment, are favorable for the generation of secondary biogenic gas, but not thermogenic gas or primary biogenic gas.

关键词： present geo-temperature thermal conductivity heat flow coalbed gas resource effect coal measure Huaibei coalfield

Comparison of coalbed gas generation between Huaibei-Huainan coalfields and Qinshui coal basin based on the tectono-thermal modeling

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Science China Earth Sciences 2011年第7期54卷 1069-1077页

作者： WU YuDong ju yiwen HOU QuanLin HU ShengBiao PAN JieNan FAN junJia College of Earth Science Graduate University of the Chinese Academy of Sciences Beijing 100049 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Resources & Environment Henan Polytechnic University Henan 454000 China

The geothermal history and the tectonic subsidence history of the Huaibei-Huainan coalfields were reconstructed by using the vitrinite reflectance data, and their correlative restriction on coalbed gas generation of Huaibei-Huainan coalfields and Qinshui coal basin was discussed. The burial, thermal, and maturity histories of are similar between Huaibei coalfield and Huainan coalfield, obviously different from those of Qinshui coal basin. Based on the tectono-thermal evolution characters of Huaibei-Huainan coalfields and Qinshui basin, the process of coalbed gas generation can be divided into three stages：（1） Dur- ing Early Mesozoic, both in Huaibei-Huainan and Qinshui, the buried depth of Permian coal seams increased rapidly, which resulted in strong metamorphism and high burial temperature of coal seams. At this stage, the coal rank was mainly fat coal, and locally reached coking coal. These created an environment favoring the generation of thermogenic gas. （2） From Late ju- rassic to Cretaceous, in the areas of Huaibei-Hualnan, the strata suffered from erosion and the crust became thinning, and the Permian coal-bearing strata were uplifted to surface. At this stage, the thermogenic gas mostly escaped. Conversely, in Qinshui basin, the cover strata of coal seams kept intact during this stage, and the thermogenic gas were mostly preserved. Furthermore, with the interaction of magmatism, the burial temperature of coal seams reached higher peak value, and it was suitable for the secondary generation of thermogenic gas. （3） From Paleogene onward, in area of Huainan-Huaibei, the maturity of coal and burial temperature were propitious to the generation of secondary biogenic gases. However, in Qinshui basin, the maturity of coal went against genesis of second biogenic gas or thermogenic gas. By comparison, Huaibei-Huainan coalfields are dominated by thermogenic gas with a significant biogenic gas and hydrodynamic overprint, whereas Qinshui basin is dominated mainly by t

关键词： HuaiBei coalfield Huainan coalfield Qinshui coal basin tectono-thermal modeling coalbed gas generation