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水力渗透型煤矿采空区三维音频大地电磁快速解译

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矿业安全与环保 2024年第1期51卷 70-77页

作者：王楠王子健秦其明孙千惠李树超北京信息科技大学网络文化与数字传播北京市重点实验室北京100192 北京信息科技大学计算机学院北京100192 北京大学遥感与地理信息系统研究所北京100871 中国昆仑工程有限公司北京100037 中国科学院空天信息创新研究院北京100190

煤矿采空区或回采阶段工作面常面临水力渗透威胁,如何快速有效且低成本地预判水力渗透成为难题。提出并系统论述了一种面向水力渗透型采空区的音频大地电磁三维反演及快速解译方案。通过设计采空区理论地电模型,探讨采空区电阻率三维反... 详细信息

煤矿采空区或回采阶段工作面常面临水力渗透威胁,如何快速有效且低成本地预判水力渗透成为难题。提出并系统论述了一种面向水力渗透型采空区的音频大地电磁三维反演及快速解译方案。通过设计采空区理论地电模型,探讨采空区电阻率三维反演可行性。实测数据反演解释结果揭示:采空区巷道顶板区域存在明显低阻分布,部分工作面存在顶板裂隙导水造成的富水低阻区域,局部垮落带与上覆含水层明显连通。为可疑透水位置定位、水位和涌水量监测,以及后续开采规划制订提供了参考。从理论和实证角度,为音频大地电磁法的采空区富水状态分析和动态监控应用提供了新思路,相关方法能够有效提高水力渗透型采空区的解译效果。

关键词：煤矿采空区水力渗透天然源音频大地电磁法三维反演

A Novel Dynamic Stretching Solution to Eliminate Saturation Effect in NDVI and Its Application in Drought Monitoring

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Chinese Geographical Science 2012年第6期22卷 683-694页

作者： LIU Fang qin qiming ZHAN Zhiming School of Earth and Space Science Peking University Beijing 100871 China Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China

The normalized difference vegetation index(NDVI) is one of the key input variables for developing drought ***,the NDVI quickly saturates in high vegetation surfaces,and thus,the generalization of a drought index over different ecosystems becomes a *** paper presents a novel,dynamic stretching algorithm to overcome the saturation effect in NDVI.A scaling transformation function to eliminate saturation effects when the vegetation fraction(VF) is large is *** range adjustment is conducted using three coefficients,namely,the normalization factor(a),the stretching range controlling factor(m),and the stretching size controlling factor(e).The results show that the stretched NDVI(S-NDVI) is more sensitive to vegetation fraction than NDVI when the VF is large,ranging from 0.75 to ***,the saturation effect in NDVI is effectively removed by using the *** analysis suggests that there is a good linear correlation between the S-NDVI and the leaf area index(LAI).At the same time,the proposed S-NDVI significantly reduces or even eliminates the saturation effect over high biomass.A comparative analysis is performed between drought indices derived from NDVI and S-NDVI,*** the experiment,reflectance data from the moderate resolution imaging spectroradiometer(MODIS) products and in-situ observation data from the meteorological sites at a regional scale are *** this study,the coefficient of determination(R2) of the stretched drought index(S-DI) is above 0.5,indicating the reliability of the proposed algorithm with surface soil moisture ***,the S-DI is suggested to be used as a drought index in extended regions,thus regional heterogeneity should be taken into account when applying stretching method.

关键词： drought monitoring saturation effect scaling transformation NDVI MODIS remote sensing

Passive Super-Low Frequency electromagnetic prospecting technique

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Frontiers of Earth Science 2017年第2期11卷 248-267页

作者： Nan WANG Shanshan ZHAO Jian HUI qiming qin Institute of Remote Sensing and GIS School of Earth and Space Sciences Peking University Beijing 100871 China Key Laboratory of Technology in Geospatial Information Processing and Application System Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

The Super-Low Frequency （SLF） electromag- netic prospecting technique, adopted as a non-imaging remote sensing tool for depth sounding, is systematically proposed for subsurface geological survey. In this paper, we propose and theoretically illustrate natural source magnetic amplitudes as SLF responses for the first step. In order to directly calculate multi-dimensional theoretical SLF responses, modeling algorithms were developed and evaluated using the finite difference method. The theore- tical results of three-dimensional （3-D） models show that the average normalized SLF magnetic amplitude responses were numerically stable and appropriate for practical interpretation. To explore the depth resolution, three-layer models were configured. The modeling results prove that the SLF technique is more sensitive to conductive objective layers than high resistive ones, with the SLF responses of conductive objective layers obviously show- ing uprising amplitudes in the low frequency range. Afterwards, we proposed an improved Frequency-Depth transformation based on Bostick inversion to realize the depth sounding by empirically adjusting two parameters. The SLF technique has already been successfully applied in geothermal exploration and coalbed methane （CBM） reservoir interpretation, which demonstrates that the proposed methodology is effective in revealing low resistive distributions. Furthermore, it siginificantly contributes to reservoir identification with electromagnetic radiation anomaly extraction. Meanwhile, the SLF inter- pretation results are in accordance with dynamic production status of CBM reservoirs, which means it could provide an economical, convenient and promising method for exploring and monitoring subsurface geo-objects.

关键词： Super-Low Frequency (SLF) three-dimen-sional modeling frequency-depth transformation geother-mal exploration coalbed methane (CBM) electromagneticradiation (EMR)

Evaluation of the Visible and Shortwave Infrared Drought Index in China

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International Journal of Disaster Risk Science 2013年第2期4卷 68-76页

作者： Ning Zhang Yang Hong qiming qin Lin Zhu Institute of Remote Sensing and GIS Peking UniversityBeijing 100871China School of Civil Engineering and Environmental Sciences University of OklahomaOK 73072USA National Satellite Meteorological Center of China Meteorological Administration Beijing 100081China

In this article, the performance of the Visible and Shortwave infrared Drought Index(VSDI), a drought index recently developed and validated in Oklahoma, United States, is further explored and validated in China. The in-situ measured soil moisture from 585 weather stations across China are used as ground-truth data, and five commonly used drought indices are compared with VSDI for surface drought monitoring. The results reveal that VSDI is robust and reliable in the estimation of surface dryness—it has the highest correlation with soil moisture among the six indices when computed using both the original and cloud removed data. All six indices show the highest correlation with soil moisture at the 10 cm layer and the averaged 10–50 cm layer. The spatiotemporal patterns of surface moisture indicated by the MODIS-based VSDI are further compared with the precipitation-based drought maps and the Global Land Data Assimilation System(GLDAS) simulated surface soil moisture maps over five provinces located in the Middle-Lower Yangtze Plain of China. The results indicate that despite the difference between the spatial and temporal resolutions of the three products, the VSDI maps still show good agreement with the other two drought products through the rapidly alternating drought and flood events in 2011 in this region. Therefore, VSDI can be used as an effective surface wetness indicator at both the provincial and the national scales in China.

关键词： China. drought moisture

Definitions of Natural-Language Spatial Relations: Combining Topology and Directions

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Geo-Spatial Information Science 2006年第1期9卷 55-64页

作者： DU Shihong WANG Qiao qin qiming Institute of Remote Sensing and GIS Peking University 5 Yiheyuan Road Haidian District Beijing 100871 China

Because SQL for querying data from spatial databa se s is ineffective, the query based on natural or visual language becomes an attra ctive research field gradually. However, how to define and represent natural lan guages related to spatial data are still gigantic problems. Because existing mod els of direction relations can’t describe by use of some common concepts. First of all, detailed direction relations are proposed to describe the directions re lated to the interior of spatial objects, such as "east part of a region","ea st boundary of a region", and so on. Secondly, by integrating the detailed dire ctions with exterior direction relations and topological relations, several NLSR s are defined, such as "a road goes across the east part of a lake", "a river goes along the east boundary of a province", etc. Finally, based on the NLSRs abovementioned, a natural spatial query language (NSQL) is formed to retrieve da ta from spatial databases.

关键词： geographic information system topological relations direction relations detailed direction relations natural-language spatial relations

PBL亚型联合CTC对儿童肝母细胞瘤预后的预测价值

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郑州大学学报（医学版） 2024年第5期59卷 712-715页

作者：张景畅张天佑师文楷秦启明赵永福郑州大学第一附属医院肝胆胰外科郑州450052

目的:探究外周血淋巴细胞(PBL)亚型与循环肿瘤细胞(CTC)联合对儿童肝母细胞瘤(HB)术后生存的预测价值。方法:选取2018年6月至2022年6月于郑州大学第一附属医院接受肿瘤切除术的HB患儿116例,随访并记录患儿术后12个月的生存状态。采集患... 详细信息

目的:探究外周血淋巴细胞(PBL)亚型与循环肿瘤细胞(CTC)联合对儿童肝母细胞瘤(HB)术后生存的预测价值。方法:选取2018年6月至2022年6月于郑州大学第一附属医院接受肿瘤切除术的HB患儿116例,随访并记录患儿术后12个月的生存状态。采集患者术前静脉血,检测PBL亚型及CTC。采用Logistic回归构建PBL亚型联合CTC的预后预测模型。绘制ROC曲线,评价联合预测模型与单一指标对HB患儿预后的预测效能。结果:联合预测模型为Logit(P)=-20.297+0.192×CD3^(+)+1.511×CD4^(+)/CD8^(+)+0.383×CTC。CD3^(+)、CD4^(+)/CD8^(+)、CTC及联合预测模型预测HB患儿术后生存的AUC(95%CI)分别为0.634(0.488~0.780)、0.606(0.487~0.725)、0.822(0.735~0.909)、0.865(0.786~0.944),联合预测模型与单一指标相比具有更好的预测效能。结论:CTC、CD3^(+)、CD4^(+)/CD8^(+)联合预测模型可用于HB患儿术后的生存预测。

关键词：肝母细胞瘤外周血淋巴细胞亚型循环肿瘤细胞

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A new method for the extraction of tailing ponds from very high-resolution remotely sensed images:PSVED

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International Journal of Digital Earth 2023年第1期16卷 2681-2703页

作者： Chengye Zhang Jianghe Xing Jun Li Shouhang Du qiming qin College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijingPeople’s Republic of China Key Laboratory of Coupling Process and Effect of Natural Resources Elements BeijingPeople’s Republic of China Institute of Remote Sensing and Geographic Information System School of Earth and Space SciencesPeking UniversityBeijingPeople’s Republic of China

Automatic extraction of tailing ponds from Very High-Resolution(VHR)remotely sensed images is vital for mineral resource *** study proposes a Pseudo-Siamese Visual Geometry Group Encoder-Decoder network(PSVED)to achieve high accuracy tailing ponds extraction from VHR ***,handcrafted feature(HCF)images are calculated from VHR images based on the index calculation algorithm,highlighting the tailing ponds'***,considering the information gap between VHR images and HCF images,the Pseudo-Siamese Visual Geometry Group(Pseudo-Siamese VGG)is utilized to extract independent and representative deep semantic features from VHR images and HCF images,***,the deep supervision mechanism is attached to handle the optimization problem of gradients vanishing or exploding.A self-made tailing ponds extraction dataset(TPSet)produced with the Gaofen-6 images of part of Hebei province,China,was employed to conduct *** results show that the proposed'method_achieves the best visual performance and accuracy for tailing ponds extraction in all the tested methods,whereas the running time of the proposed method maintains at the same level as other *** study has practical significance in automatically extracting tailing ponds from VHR images which is beneficial to tailing ponds management and monitoring.

关键词： Semantic segmentation tailing storage facilities Pseudo-Siamese network VHR images deep supervision mechanism

Satellite detection of increases in global land surface evapotranspiration during 1984-2007

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International Journal of Digital Earth 2012年第4期5卷 299-318页

作者： Yunjun Yao Shunlin Liang qiming qin Kaicun Wang Shaomin Liu Shaohua Zhao College of Global Change and Earth System Science Beijing Normal UniversityBeijingChina Department of Geography University of MarylandCollege ParkMDUSA Institute of Remote Sensing and GIS Peking UniversityBeijingChina State Key Laboratory of Remote Sensing Science School of GeographyBeijing Normal UniversityBeijingChina Environmental Satellite Center Ministry of Environmental ProtectionBeijingChina

As a key component of digital earth,remotely sensed data provides the compelling evidence that the amount of water vapour transferred from the entire global surface to the atmosphere increased from 1984 to *** validation results from the earlier evapotranspiration(ET)estimation algorithm based on net radiation(Rn),Normalised Difference Vegetation Index(NDVI),air temperature and diurnal air temperature range(DTaR)showed good agreement between estimated monthly ET and ground-measured ET from 20 flux *** analysis indicates that the estimated actual ET has increased on average over the entire global land surface except for Antarctica during 1984***,this increasing trend disappears after 2000 and the reason may be that the decline in net radiation and NDVI during this period depleted surface soil ***,the good correspondence between the precipitation trend and the change in ET in arid and semi-arid regions indicated that surface moisture linked to precipitation affects *** input parameters Rn,Tair,NDVI and DTaR show substantial spatio-temporal variability that is almost consistent with that of actual ET from 1984 to 2007 and contribute most significantly to the variation in actual ET.

关键词： digital earth evapotranspiration global land surface satellite radiation products

肿瘤负荷和炎症指标对接受三联治疗中晚期肝细胞癌预后的预测价值

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肿瘤基础与临床 2024年第5期37卷 522-528页

作者：张天佑赵双强张景畅秦启明师文楷张国坤赵永福郑州大学第一附属医院肝胆胰外科河南郑州450052

目的探究治疗前肿瘤负荷和炎症相关指标对接受经导管肝动脉化疗栓塞(TACE)、酪氨酸激酶抑制剂(TKI)及免疫检查点抑制剂(ICIs)三联治疗的中晚期肝细胞癌(HCC)患者预后的预测价值,并构建相应的预后预测模型。方法回顾性分析2020年1月至202... 详细信息

目的探究治疗前肿瘤负荷和炎症相关指标对接受经导管肝动脉化疗栓塞(TACE)、酪氨酸激酶抑制剂(TKI)及免疫检查点抑制剂(ICIs)三联治疗的中晚期肝细胞癌(HCC)患者预后的预测价值,并构建相应的预后预测模型。方法回顾性分析2020年1月至2021年12月在郑州大学第一附属医院接受TACE、TKI及ICIs三联治疗的114例中晚期HCC患者的临床资料,以疾病无进展生存时间(PFS)为主要研究终点,将患者的肿瘤负荷指标、炎症相关指标以及其他一般临床指标纳入单因素及多因素COX回归分析,筛选出患者PFS的独立危险因素。基于筛选的独立危险因素构建一种新的联合预后预测模型,通过Kaplan-Meier生存分析及受试者工作特征(ROC)曲线对比新模型与单一指标、传统分期法对患者预后的预测价值。结果通过单因素与多因素COX回归分析可知,影响接受TACE、TKI及ICIs三联治疗的中晚期HCC患者PFS的独立危险因素分别包括肿瘤负荷评分(TBS)(临界值7.96)(HR=3.421;95%CI:2.112~5.541;P7.96、NLR>3.10记为1分,根据患者得分情况可分为0分、1分、2分组,即高、中、低敏感组,其中位PFS分别为16.0个月(95%CI:12.359~19.641;P<0.001)、9.0个月(95%CI:7.693~10.307;P<0.001)、5.0个月(95%CI:2.600~7.400;P<0.001)。ROC分析结果显示,TBS-NLR模型在预测ORR和疾病控制率方面优于单一指标TBS、NLR及中国肝癌分期,AUC值最高,分别为0.819和0.803。结论TBS和NLR是接受TACE、TKI及ICIs三联治疗的中晚期HCC患者PFS的独立危险因素。由此构建的TBS-NLR模型比单一指标具有更好的预后预测效能,高敏感组及中敏感组患者更可能在TACE、TKI及ICIs三联治疗中取得生存获益,此可为中晚期HCC患者的治疗提供一定帮助。

关键词：肝细胞癌炎症肿瘤负荷评分联合治疗预后