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Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines
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作者 Chengkai Fan Na Zhang +1 位作者 Bei Jiang Wei Victor Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期727-740,共14页
Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challe... Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challenging when training data(e.g.truck haulage information and weather conditions)are massive.In machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden layers.This study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training data.Before the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input variables.To verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark models.The DNN model with multiple hidden layers performed better than the ANN models with a single hidden layer.The DNN model outperformed the extensively applied benchmark models in predicting ore production.This can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines. 展开更多
关键词 Oil sands production open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering
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Solution to the Horizontal Crossing Problem of Transportation System at Key Points in Open-Pit Mines
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作者 Tao DONG Ling LIU 《Asian Agricultural Research》 2024年第7期36-38,47,共4页
In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production... In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production,the separate transportation mode of underpass bridge and overpass steel trestle is proposed to optimize the open pit development transportation system,so as to solve the practical problems that the horizontal cross of transport vehicles causes vehicle blockage,affects production schedule and production safety.The results show that the horizontal crossing road can be changed into a separate type of overpass steel trestle,which can realize the classified transportation of large and small vehicles,reduce the traffic density,make vehicles with different functions go their own way,eliminate the hidden danger of traffic accidents,and improve the production efficiency. 展开更多
关键词 open-pit mines Cross-transport Underpass bridge Overpass steel trestle Production efficiency
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Study on the Application of Real-Time Drone Monitoring in Ordos Open-Pit Coal Mine
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作者 Junyi Wu Weizheng Wang Xuesong Ni 《Open Journal of Applied Sciences》 CAS 2023年第4期483-495,共13页
In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detecti... In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detection by existing conventional monitoring methods, this paper establishes an open-pit mine monitoring data set, and proposes a real-time intelligent monitoring model based on UAV. The reasoning component with strong computing power and low power consumption is selected, and the lightweight object detection model is selected for the experiment. A quantitative standard of dynamic energy consumption detection by evaluation algorithm is proposed. Through experimental comparison, it is found that YOLOv4-tiny has the highest comprehensive grade in detection accuracy, speed, energy consumption and other aspects, which is suitable for application in the above model. 展开更多
关键词 open-pit Mine Safety Monitoring UAV Object Detection
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2013-2022年北京市朝阳区HIV确证实验结果分析
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作者 黄平 孙灵利 +2 位作者 李崇 李丽 刘洁 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第5期478-482,共5页
目的分析2013-2022年北京市朝阳区筛查结果为阳性的HIV(艾滋病)病毒确证实验结果,了解辖区内HIV检测工作情况。方法辖区内58家筛查实验室上送的13128份HIV筛查阳性样本,通过免疫印迹实验(Western blot,WB)进行确证实验,应用SPSS22.0对... 目的分析2013-2022年北京市朝阳区筛查结果为阳性的HIV(艾滋病)病毒确证实验结果,了解辖区内HIV检测工作情况。方法辖区内58家筛查实验室上送的13128份HIV筛查阳性样本,通过免疫印迹实验(Western blot,WB)进行确证实验,应用SPSS22.0对实验结果进行统计学分析。结果2013-2022年本确证实验室检出HIV-1抗体阳性样本8417件,HIV-2阳性样本未检出,不确定样本1263份,阴性样本3448份。HIV-1抗体阳性中,男性占94.32%,性别差异有统计学意义;年龄在19~30岁组占48.65%;WB条带中全条带和次全带占96.92%,其中gp160检出率为99.94%,gp120检出率为99.67%。结论2013-2022年北京市朝阳区HIV-1抗体阳性以男性为主,年龄主要分布在19到30岁。不同年龄、性别、职业和送检人群的HIV-1抗体不确定的构成比差异不大。HIV-1抗体阳性样本的WB条带显示全条带和次全带占比最高。 展开更多
关键词 朝阳区 HIV 确证实验 条带
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2023年北京市朝阳区5家哨点医院呼吸道多病原监测分析
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作者 张士尧 路冉 +3 位作者 王媛杰 王海滨 赵剑虹 孙灵利 《实用医技杂志》 2024年第8期533-538,共6页
目的分析2023年北京市朝阳区5家哨点医院呼吸道多病原监测结果,及时掌握朝阳区呼吸道感染性疾病的流行特征。方法收集2023年1月至12月北京市朝阳区5家哨点医院1321例呼吸道患者,所有患者均采集咽拭子,使用多重荧光定量聚合酶链反应(PCR... 目的分析2023年北京市朝阳区5家哨点医院呼吸道多病原监测结果,及时掌握朝阳区呼吸道感染性疾病的流行特征。方法收集2023年1月至12月北京市朝阳区5家哨点医院1321例呼吸道患者,所有患者均采集咽拭子,使用多重荧光定量聚合酶链反应(PCR)进行检测甲型流感病毒、季节性甲3型流感病毒、新型甲型H1N1流感病毒、乙型流感病毒、乙型流感病毒BV系、乙型流感病毒BY系、新冠病毒N基因、新冠病毒ORF1ab基因、肺炎支原体、呼吸道合胞病毒、腺病毒、鼻病毒、副流感1型、副流感2型、副流感3型、副流感4型、人偏肺病毒、肠道病毒、冠状病毒HKU1、冠状病毒229E、冠状病毒OC43、冠状病毒NL63和肺炎衣原体。结果多病原检查结果显示,单一病原检测阳性标本633例,复合感染(≥2种病原体)检出76例。不同性别患者病原检出率相比较差异均无统计学意义(P>0.05);不同年龄患者腺病毒、呼吸道合胞病毒、肺炎支原体、新型冠状病毒、乙型流感病毒BV系、季节性甲3型流感病毒和人偏肺病毒相比较差异有统计学意义(P<0.05);不同季度鼻病毒、人偏肺病毒、肠道病毒和副流感2型检出率相比较差异无统计学意义(P>0.05),其他病原检出率相比较差异有统计学意义(P<0.05)。不同季节间年龄构成比相比较差异有统计学意义(P<0.05)。不同病例类型冠状病毒229E、季节性甲3型流感病毒、乙型流感病毒BV系和腺病毒检出率相比较差异有统计学意义(P<0.05),均容易引发急性上呼吸道感染。结论2023年北京市朝阳区呼吸道感染患者,病原检出率前5位是季节性甲3型流感病毒、肺炎支原体、呼吸道合胞病毒、新冠病毒和腺病毒,性别对病原检出率无显著影响,病原检出具有明显的年龄、季度和病例类型等相关特征。 展开更多
关键词 呼吸道感染 哨点监测 病原菌 北京市朝阳区
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国土空间背景下的朝阳市生态安全格局规划
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作者 付士磊 罗重骥 《沈阳建筑大学学报(社会科学版)》 2024年第2期179-184,共6页
构建生态安全格局可为国土空间规划提供全域生态问题分析和解决对策,弥补现有国土空间生态规划的不足。以朝阳市为例,在国土空间规划的大背景下,基于景观联通性理论、最小累计阻力模型及电路理论等相关理论模型提取生态源地、生态阻力... 构建生态安全格局可为国土空间规划提供全域生态问题分析和解决对策,弥补现有国土空间生态规划的不足。以朝阳市为例,在国土空间规划的大背景下,基于景观联通性理论、最小累计阻力模型及电路理论等相关理论模型提取生态源地、生态阻力面、生态廊道和生态夹点,构建了朝阳市“一轴两带、东西两屏、五心多点”总体生态安全格局。通过对朝阳市生态安全格局的构建,体现了山水林田湖草生命共同体思想,突出了不同生态要素之间的联系,为同类城市的国土空间规划提供了支撑。 展开更多
关键词 生态安全格局 国土空间 生态规划 朝阳市
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朝阳地区玉米机械化耕种模式效益分析
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作者 吕东山 《农业科技与装备》 2024年第2期36-37,共2页
为了适应朝阳市保护性耕作的发展需要,针对朝阳地区的玉米机械化耕种模式进行了效益分析。结果表明,保护性耕作模式平均增产64.5 kg/667 m^(2),单位面积节约成本34.71元/667 m^(2),推广应用保护性耕作机械化技术对扭转半干旱地区旱灾频... 为了适应朝阳市保护性耕作的发展需要,针对朝阳地区的玉米机械化耕种模式进行了效益分析。结果表明,保护性耕作模式平均增产64.5 kg/667 m^(2),单位面积节约成本34.71元/667 m^(2),推广应用保护性耕作机械化技术对扭转半干旱地区旱灾频繁、水土流失严重、生态环境恶化等不利局面具有重要意义。 展开更多
关键词 朝阳地区 保护性耕作 免耕 深松 效益分析
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Optimization model of GNSS/pseudolites structure design for open-pit mine positioning 被引量:4
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作者 单正英 韩厚增 姜昆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2201-2208,共8页
A new pseudolites (PLs) structure optimization model of global navigation satellite system (GNSS)/PLs integration positioning system used in deep open-pit mine was presented. Position dilution of precision (Pdop... A new pseudolites (PLs) structure optimization model of global navigation satellite system (GNSS)/PLs integration positioning system used in deep open-pit mine was presented. Position dilution of precision (Pdop) and reliability were selected as the optimization indicators to build a multi-objective optimization model to decide the optimum PLs location. A scheme was designed by establishing a four-dimensional model taking azimuth (a), elevation angle (e) and epoch (t) of satellites as the input independent variables and Pdop as the dependent variable to calculate the optimum PLs location zone considering the real circumstances. And then the ultimate PLs location can be fixed by testing the curves of Pdop along time. A field collected Trimble R8 GPS data set in China University of Mining and Technology (CUMT) campus was used for the model test to show the effectiveness, and the proposed PLs optimum design scheme was used at the west open-pit mine of Fushun mining group Co., Ltd., in China, better Pdop and reliability have been achieved for the integration system. Both experiments show that the proposed scheme is excellent in designing GNSS/PLs system which is helpful for improving the performance of the positioning system and reducing the cost. 展开更多
关键词 open-pit mine dilution of precision RELIABILITY GNSS/PLs system OPTIMIZATION
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Modified algorithm of combined GPS/GLONASS precise point positioning for applications in open-pit mines 被引量:2
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作者 蔡昌盛 罗小敏 朱建军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1547-1553,共7页
A modified algorithm of combined GPS/GLONASS precise point positioning (GG-PPP) was developed by decreasing the number of unknowns to be estimated so that accurate position solutions can be achieved in the case of l... A modified algorithm of combined GPS/GLONASS precise point positioning (GG-PPP) was developed by decreasing the number of unknowns to be estimated so that accurate position solutions can be achieved in the case of less number of visible satellites. The system time difference between GPS and GLONASS (STDGG) and zenith tropospheric delay (ZTD) values were firstly estimated in an open sky condition using the traditional GG-PPP algorithm. Then, they were used as a priori known values in the modified algorithm instead of estimating them as unknowns. The proposed algorithm was tested using observations collected at BJFS station in a simulated open-pit mine environment. The results show that the position filter converges much faster to a stable value in all three coordinate components using the modified algorithm than using the traditional algorithm. The modified algorithm achieves higher positioning accuracy as well. The accuracy improvement in the horizontal direction and vertical direction reaches 69% and 95% at a satellite elevation mask angle of 50°, respectively. 展开更多
关键词 GPS GLONASS precise point positioning elevation mask angle open-pit mine
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Influence of Global Warming on High-active Agricultural Development in Chaoyang Area 被引量:1
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作者 周广学 李普庆 周晓东 《Meteorological and Environmental Research》 CAS 2010年第3期42-44,共3页
The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in... The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in protective field,gross agricultural output value.The results showed that climate warming had a very significant positive effect on the development of high-active agriculture in Chaoyang. 展开更多
关键词 chaoyang area INFLUENCE High-active agriculture China
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新水情背景下北京平原朝阳—通州沉降区地面沉降特征及其影响
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作者 韩红闪 朱琳 +2 位作者 郭高轩 李炳华 卢灿 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第4期1326-1338,共13页
地面沉降是北京地区突出的地质灾害,严重威胁经济、环境和社会的可持续发展。为了研究地面沉降的时空特征及其影响,本文以北京平原朝阳—通州沉降区为研究对象,先基于Sentinel-1 A/B卫星降轨数据,利用PS-InSAR(persistent scatters InS... 地面沉降是北京地区突出的地质灾害,严重威胁经济、环境和社会的可持续发展。为了研究地面沉降的时空特征及其影响,本文以北京平原朝阳—通州沉降区为研究对象,先基于Sentinel-1 A/B卫星降轨数据,利用PS-InSAR(persistent scatters InSAR)技术获取了研究区2019年1月—2021年12月地面沉降特征,再采用动态时间规整(DTW)算法定量分析了地面沉降与不同层位地下水位之间的响应关系,并进一步量化了不同深度地下水抽取诱发地面沉降的贡献率。结果表明:1)2019—2021年朝阳—通州地区地面沉降连片发展,年均沉降速率超过50 mm/a的沉降严重地区主要分布在朝阳区东部和通州区北部,其中最大沉降速率达到91 mm/a。2)朝阳—通州地区可压缩层厚度区域分布差异,为地面沉降的发生与发展提供了有利的地质条件。整体上来看可压缩层厚度大小与地面沉降速率成正比,研究区地面沉降速率大于80 mm/a的永久散射体(PS)点所在位置处的可压缩层厚度均大于180 m,且主要处于可压缩层厚度200~220 m的地区。3)地面沉降与不同层位地下水位时间序列响应不同,埋深为50~180 m的承压含水层水位与地面沉降响应程度相对较高,其中92.00和121.42 m深度下地下水位与地面沉降时序的响应程度最高,反映出该层位的地下水位变化是造成沉降的主要诱发因素。 展开更多
关键词 地面沉降 PS-INSAR DTW 朝阳—通州 地下水位 影响因素 北京
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朝阳盆地白垩系九佛堂组火山沉积作用及其对有机质富集的影响
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作者 张家志 姜在兴 +7 位作者 徐杰 魏思源 宋立舟 刘桐 沈志晗 姜晓龙 李永飞 张玺 《地学前缘》 EI CAS CSCD 北大核心 2024年第3期284-297,共14页
辽西朝阳盆地位于燕山构造带东段,属于松辽外围中生代的断陷盆地,勘探认识程度不高。前人研究认为,朝阳盆地下白垩统九佛堂组为湖相沉积,而忽略了火山事件对于湖盆沉积的重要影响。对此笔者通过区域地质资料调查、钻井岩心描述、岩心薄... 辽西朝阳盆地位于燕山构造带东段,属于松辽外围中生代的断陷盆地,勘探认识程度不高。前人研究认为,朝阳盆地下白垩统九佛堂组为湖相沉积,而忽略了火山事件对于湖盆沉积的重要影响。对此笔者通过区域地质资料调查、钻井岩心描述、岩心薄片资料观察以及分析测试资料等手段,在火山碎屑岩分类基础上,根据火山碎屑含量划分出沉积火山碎屑岩以及火山碎屑沉积岩,并结合粒度、组分、沉积构造等特征细分出11种岩相类型以及9种岩相组合,进而提出火山碎屑流、火山异重流、火山灰异轻流、热液侵入和微生物诱导5种成因机制。结合钻井岩心观察识别出火山沉积序列及沉积特征,建立了朝阳盆地九佛堂组火山湖泊沉积模式,为研究区油气资源的勘探开发提供理论依据。研究发现,火山物质对湖盆内有机质富集起到积极的影响。朝阳盆地九佛堂组烃源岩地化测试显示:含有火山细粒物质参与沉积的样品有机质丰度指标更好,有机质更富集。由于燕山构造带内其他盆地同样具有相似的火山活动地质背景,研究结果也为这些地区沉积学及油气资源研究起到良好的对比参照作用。 展开更多
关键词 朝阳盆地 九佛堂组 岩相类型及组合 成因机制 有机质富集
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Failure characteristics and its influencing factors of talus-derived rock mass during open-pit mining 被引量:1
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作者 王贵和 杨宇友 +1 位作者 张辉 张子新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期462-471,共10页
The failure characteristic of talus-derived rock mass continues to challenge quantitative hazard assessments in open-pit mining. Physical model test was used to assess the failure modes and mechanisms on talus-derived... The failure characteristic of talus-derived rock mass continues to challenge quantitative hazard assessments in open-pit mining. Physical model test was used to assess the failure modes and mechanisms on talus-derived rock mass. The different types of failure modes of the talus-derived rock mass were introduced and a possible failure mechanism relation between the failure zone and the structure of the talus-derived rock mass was also shown. The physical model test results indicate that the rainfall has significant influence on the stability and failure modes of talus-derived rock mass during open-pit mining. The development of the seepage area caused by rainfall initiates the localized failure in that particular area, and the initiation of localized instability is mainly induced by stress changes concentrated in the seepage area. 展开更多
关键词 talus-derived rock mass model test failure mode RAINFALL open-pit mining
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Slope stability of reclaimed coal mines through a new water filling index
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作者 Antonios Mikroutsikos Alexandros I.Theocharis +1 位作者 Nikolaos C.Koukouzas Ioannis E.Zevgolis 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期828-839,共12页
A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding ... A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding slopes.The present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s influence.The assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is identified.Furthermore,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical use.During the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial one.Overall,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect. 展开更多
关键词 Post-coal era open-pit flooding Stability charts Critical level
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Comprehensive analysis of multiple machine learning techniques for rock slope failure prediction
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作者 Arsalan Mahmoodzadeh Abed Alanazi +4 位作者 Adil Hussein Mohammed Hawkar Hashim Ibrahim Abdullah Alqahtani Shtwai Alsubai Ahmed Babeker Elhag 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4386-4398,共13页
In this study,twelve machine learning(ML)techniques are used to accurately estimate the safety factor of rock slopes(SFRS).The dataset used for developing these models consists of 344 rock slopes from various open-pit... In this study,twelve machine learning(ML)techniques are used to accurately estimate the safety factor of rock slopes(SFRS).The dataset used for developing these models consists of 344 rock slopes from various open-pit mines around Iran,evenly distributed between the training(80%)and testing(20%)datasets.The models are evaluated for accuracy using Janbu's limit equilibrium method(LEM)and commercial tool GeoStudio methods.Statistical assessment metrics show that the random forest model is the most accurate in estimating the SFRS(MSE=0.0182,R2=0.8319)and shows high agreement with the results from the LEM method.The results from the long-short-term memory(LSTM)model are the least accurate(MSE=0.037,R2=0.6618)of all the models tested.However,only the null space support vector regression(NuSVR)model performs accurately compared to the practice mode by altering the value of one parameter while maintaining the other parameters constant.It is suggested that this model would be the best one to use to calculate the SFRS.A graphical user interface for the proposed models is developed to further assist in the calculation of the SFRS for engineering difficulties.In this study,we attempt to bridge the gap between modern slope stability evaluation techniques and more conventional analysis methods. 展开更多
关键词 Rock slope stability open-pit mines Machine learning(ML) Limit equilibrium method(LEM)
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潮阳(金灶)方言的话题标记“个”
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作者 张沐舒 《汉语学报》 CSSCI 北大核心 2024年第4期117-128,共12页
广东潮阳(金灶)方言的“个”[kai^(55-22)]所标记的话题句,从形式上看,包括同一性(拷贝式)话题句和论元共指性话题句;从语义和语用上看,这些话题句主要有对比(包括极性对比和让步转折)、强调、反预期感叹和总括性评价等功能。“个”在... 广东潮阳(金灶)方言的“个”[kai^(55-22)]所标记的话题句,从形式上看,包括同一性(拷贝式)话题句和论元共指性话题句;从语义和语用上看,这些话题句主要有对比(包括极性对比和让步转折)、强调、反预期感叹和总括性评价等功能。“个”在金灶方言中可用于谓词性和体词性话题成分之后,是较成熟的话题标记。“个”有强调话题对比性的作用,是标示金灶方言对比性话题的主要形式手段。 展开更多
关键词 潮阳(金灶)方言 话题标记 “个” 对比话题
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天津蓟州区朝阳洞遗址2号地点发掘简报
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作者 魏天旭 王春雪 +2 位作者 张雪微 王家琪 盛立双 《人类学学报》 CSSCI CSCD 北大核心 2024年第2期314-320,共7页
朝阳洞遗址是天津市首个发掘的旧石器时代洞穴遗址。该遗址在2015年旧石器专项调查中发现。2019年7-9月,天津市文化遗产保护中心联合吉林大学考古学院对其进行发掘。该遗址由1号地点和2号地点组成,1号地点出土了陶器、石制品和动物化石,... 朝阳洞遗址是天津市首个发掘的旧石器时代洞穴遗址。该遗址在2015年旧石器专项调查中发现。2019年7-9月,天津市文化遗产保护中心联合吉林大学考古学院对其进行发掘。该遗址由1号地点和2号地点组成,1号地点出土了陶器、石制品和动物化石,2号地点仅出土了石制品。本文只研究2号地点出土的石制品,包括石片和石器。从石片特征判断,2号地点剥片技术为直接锤击法。石器的类型简单,只有刮削器和凹缺器两类,均以石片为毛坯。通过地质地层对比以及石器工业面貌,推测其年代应为旧石器时代晚期。朝阳洞遗址的发现不仅为构建天津地区旧石器时代的年代序列增添了新材料,而且对揭示该地区的早期人类行为具有重要意义。 展开更多
关键词 晚更新世 石制品 天津蓟州区 朝阳洞遗址
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新时代首都老年教育实践与思考——以北京市朝阳区为例
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作者 陈琢 齐媛 《继续教育研究》 2024年第7期39-44,共6页
发展新时代首都老年教育,是全面贯彻落实党中央关于应对人口老龄化一系列决策部署的必然要求,更是北京探索特大型城市人口老龄化和养老工作创新发展的现实需要。近年来,北京市进行了积极的实践,以朝阳区为代表形成了独具特色的老年教育... 发展新时代首都老年教育,是全面贯彻落实党中央关于应对人口老龄化一系列决策部署的必然要求,更是北京探索特大型城市人口老龄化和养老工作创新发展的现实需要。近年来,北京市进行了积极的实践,以朝阳区为代表形成了独具特色的老年教育理论实践体系、资源整合机制和优质品牌,但同时也面临管理机制尚未理顺、经费投入尚不充足、资源供给尚不充分等普遍性发展困境。需从顶层设计、资源供给、平台载体、氛围营造等方面系统发力,以首善标准推动首都老年教育工作高质量发展。 展开更多
关键词 老年教育 首都 北京市朝阳区 养教结合 首善标准
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朝阳市生猪生产形势分析及应对策略
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作者 王久媛 常志宏 《饲料博览》 CAS 2024年第1期30-34,共5页
我国是猪肉生产大国,也是消费大国。生猪产业是我国畜牧业的重要支柱产业,与百姓生活密切相关。但当前我国生猪产业正处于低谷修复阶段,面对产能过剩、生猪市场行情低迷的现状,如何有效破解养猪业短板获取收益成为研究热点。文章以辽宁... 我国是猪肉生产大国,也是消费大国。生猪产业是我国畜牧业的重要支柱产业,与百姓生活密切相关。但当前我国生猪产业正处于低谷修复阶段,面对产能过剩、生猪市场行情低迷的现状,如何有效破解养猪业短板获取收益成为研究热点。文章以辽宁省朝阳市生猪生产现状为例,主要阐述了近年来辽宁省朝阳市生猪生产形势,并进行了原因剖析,针对目前生猪养殖现状,提出切实可行的建议,为生猪生产持续健康发展提供相关参考。 展开更多
关键词 朝阳市 生猪 生产形势 市场行情 价格
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不同降雨工况下地质灾害综合评价--以汕头市潮阳区金灶镇重点调查区为例
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作者 李建颖 蔡文权 +2 位作者 张国沅 纪振付 张明亮 《中国资源综合利用》 2024年第10期81-87,92,共8页
汕头市潮阳区地处广东省东部,人口密度大,地质环境条件复杂。以汕头市潮阳区金灶镇重点调查区为例,选取斜坡坡度、地形起伏度、工程地质岩组和土地利用类型等指标,运用ArcGIS软件开展地质灾害易发性评价,然后结合不同降雨工况下历史日... 汕头市潮阳区地处广东省东部,人口密度大,地质环境条件复杂。以汕头市潮阳区金灶镇重点调查区为例,选取斜坡坡度、地形起伏度、工程地质岩组和土地利用类型等指标,运用ArcGIS软件开展地质灾害易发性评价,然后结合不同降雨工况下历史日降雨量数据(10年、20年、50年和100年),采用ArcGIS软件进行地质灾害危险性评价,并以斜坡单元为评价单元,使用ArcGIS软件开展区域地质灾害风险评价,得到4种降雨工况的风险分区。研究表明,随着降雨重现期的延长,低风险区逐渐减少,高风险区和极高风险区逐渐增加。研究成果可指导各级地方政府防灾减灾,为汕头市潮阳区国土空间规划和地质灾害风险管控提供科学依据。 展开更多
关键词 重点调查区 地质灾害 风险评价 降雨 ArcGIS软件 汕头市潮阳区
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