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基于PIT技术的老口航运枢纽鱼道通行效率及鱼类行为分析
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作者 宋韵涛 曾令锋 +5 位作者 谭细畅 吴志强 闭增钊 衷英杰 孙扬言 乔梁 《农业工程学报》 EI CAS CSCD 北大核心 2024年第8期216-222,共7页
PIT(passive integrated transponder)射频芯片跟踪作为一种监测方法,被广泛应用于鱼类洄游行为监测及评估鱼道过鱼效率。为了解鱼类在郁江老口航运枢纽鱼道的上溯速度、昼夜特征行为及鱼道通行效率等情况,从而为鱼道设计提供更多参考,... PIT(passive integrated transponder)射频芯片跟踪作为一种监测方法,被广泛应用于鱼类洄游行为监测及评估鱼道过鱼效率。为了解鱼类在郁江老口航运枢纽鱼道的上溯速度、昼夜特征行为及鱼道通行效率等情况,从而为鱼道设计提供更多参考,该研究以优势种鲮(Cirrhinus molitorella)为试验对象,搭半双工(half duplex,HDX)PIT标记射频芯片跟踪系统,在鱼道中设置了5个监测断面。有效试验鱼共63尾,全部为野生个体,全长范围为16.00~23.50 cm,均值为(19.05±1.49)cm。试验发现,试验鱼在白天活动较为活跃,夜晚则处于休息状态;多数个体在标记放流后上行至第一个天线所需时间超过10 h;标记试验鱼通过整个鱼道的历时为648~5359 min,总通行效率为50.79%。研究可为国内过鱼设施通行效率量化及鱼道中鱼类上溯行为特征研究提供参考。 展开更多
关键词 鱼道 监测 pit标记 过鱼效率 行为模式
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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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PIT标志技术在鱼类资源保护中的应用研究
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作者 王宇亮 谢意军 +3 位作者 黄晋 袁劲松 姜昊 徐珊霞 《安徽农业科学》 CAS 2024年第17期1-5,26,共6页
PIT(passive integrated transponder)标记因其具有储存的信息量大、持久可靠、识别迅速、性能稳定、唯一性、体积小等优点,被广泛用于鱼类种群动态、增殖放流、生境选择和过鱼设施等研究领域,成为鱼类资源保护研究的重要手段之一。介绍... PIT(passive integrated transponder)标记因其具有储存的信息量大、持久可靠、识别迅速、性能稳定、唯一性、体积小等优点,被广泛用于鱼类种群动态、增殖放流、生境选择和过鱼设施等研究领域,成为鱼类资源保护研究的重要手段之一。介绍了PIT标志技术的工作原理,梳理了1991—2020年国内外PIT标志技术在鱼类资源保护中的应用研究,探讨了PIT标志技术在鱼类种群动态、过鱼设施、增殖放流以及生境选择等研究中的成效。通过对比国内外PIT标志技术的应用研究情况,结合国内鱼类资源保护工作的实际需求与研究现状,分析了国外PIT标志技术应用研究对我国开展相关工作的指导作用,指出PIT标志技术在我国应用研究的发展方向,提出加强PIT标志技术在过鱼设施的长期监测、鱼类增殖放流、鱼类种群动态与鱼类生境选择等方面的应用研究,提升PIT标志技术在鱼类资源保护研究中的技术水平,制定PIT标记应用的技术规范,建立我国PIT标记监测网络平台等建议,以满足鱼类科研、保护和管理的需要。 展开更多
关键词 pit标志 检测技术 鱼类资源 保护 应用研究
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Rockburst criterion and evaluation method for potential rockburst pit depth considering excavation damage effect 被引量:1
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作者 Jinhao Dai Fengqiang Gong Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1649-1666,共18页
Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Ta... Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth. 展开更多
关键词 Deep tunnel ROCKBURST Rockburst pit Excavation damage effect Hoek-Brown criterion
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pit分型联合jnet分型在结直肠息肉病理分类诊断中的应用价值
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作者 齐军 方新鑫 韩怡 《川北医学院学报》 CAS 2024年第6期771-774,共4页
目的:探究pit分型联合jnet分型在结直肠息肉病理分类判断中的应用价值。方法:选取102例结直肠息肉患者(共134个病灶)为研究对象,所有患者均接受内镜及病理检查。以病理诊断结果为金标准,比较pit分型、jnet分型对各病理分类结直肠息肉的... 目的:探究pit分型联合jnet分型在结直肠息肉病理分类判断中的应用价值。方法:选取102例结直肠息肉患者(共134个病灶)为研究对象,所有患者均接受内镜及病理检查。以病理诊断结果为金标准,比较pit分型、jnet分型对各病理分类结直肠息肉的诊断符合率。采用Kappa检验分析pit分型、jnet分型单独及联合诊断结直肠息肉性质的结果与病理诊断结果的一致性。结果:pit分型II型与病理诊断为非肿瘤性息肉的符合率为88.00%(22/25);IIIL型与病理诊断为管状腺瘤的符合率为91.38%(53/58);Ⅳ型与病理诊断为绒毛状腺瘤的符合率为80.00%(16/20);Ⅵ型与病理诊断为高级别上皮内瘤变(HGIN)/粘膜下浅层浸润癌(SM-s)的符合率为85.19%(23/27);VN型与病理诊断粘膜下深层浸润癌(SM-d)的符合率为50.00%(2/4)。jnet分型1型与病理诊断为非肿瘤性息肉的符合率为80.00%(20/25);2A型与病理诊断为腺瘤性息肉的符合率为84.62%(66/78);2B型与病理诊断为HGIN/SM-s的符合率为92.59%(25/27);3型与病理诊断为SM-d的符合率为100.00%(4/4)。pit分型、jnet分型及pit分型联合jnet分型诊断肿瘤性结直肠息肉的Kappa值分别为0.809、0.714、0.925。pit分型、jnet分型单独及联合诊断结直肠息肉的敏感度分别为88.00%、80.00%、92.00%,特异度分别为95.41%、93.58%、99.08%,阳性预测值分别为81.46%、74.07%、95.83%,阴性预测值分别为97.20%、95.33%、98.18%,准确度分别为94.03%、91.04%、97.76%。结论:pit分型联合jnet分型在结直肠息肉病理分类诊断中,可提高诊断结直肠息肉性质的准确性,为临床治疗决策提供指导。 展开更多
关键词 pit分型 jnet分型 结直肠息肉 病理分类 应用价值
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Pit density reduction for AlN epilayers grown by molecular beam epitaxy using Al modulation method
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作者 Huan Liu Peng-Fei Shao +8 位作者 Song-Lin Chen Tao Tao Yu Yan Zi-Li Xie Bin Liu Dun-Jun Chen Hai Lu Rong Zhang Ke Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期95-101,共7页
We have investigated homoepitaxy of AlN films grown by molecular beam epitaxy on AlN/sapphire templates byadopting both the continuous growth method and the Al modulation epitaxy(AME)growth method.The continuous growt... We have investigated homoepitaxy of AlN films grown by molecular beam epitaxy on AlN/sapphire templates byadopting both the continuous growth method and the Al modulation epitaxy(AME)growth method.The continuous growthmethod encounters significant challenges in controlling the growth mode.As the precise Al/N=1.0 ratio is difficult toachieve,either the excessive Al-rich or N-rich growth mode occurs.In contrast,by adopting the AME growth method,sucha difficulty has been effectively overcome.By manipulating the supply time of the Al and nitrogen sources,we were able toproduce AlN films with much improved surface morphology.The first step of the AME method,only supplying Al atoms,is important to wet the surface and the Al adatoms can act as a surfactant.Optimization of the initial Al supply time caneffectively reduce the pit density on the grown AlN surface.The pits density dropped from 12 pits/μm^(2)to 1 pit/μm^(2)andthe surface roughness reduced from 0.72 nm to 0.3 nm in a 2×2μm^(2)area for the AME AlN film homoepitaxially grownon an AlN template. 展开更多
关键词 Al modulation epitaxy molecular beam epitaxy ALN pitS
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The role of the auxin-response genes MdGH3.1 and MdSAUR36 in bitter pit formation in apple
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作者 Daqing Huang Wen Peng +3 位作者 Na Gong Lina Qiu Yongzhang Wang Haiyong Qu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1085-1098,共14页
Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome anal... Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome analyses were performed to investigate BP pulp of 'Fuji'. Two auxin-response genes, MdGH3.1 and MdSAUR36, were screened. Their expression as well as the auxin content in BP pulp were found to be higher than those in healthy pulp(P < 0.01). In the field, excess CO(NH2)2increased the incidence of BP. Moreover, the auxin content and MdGH3.1 expression increased in apples after nitrogen fertilization. On Day 30 before harvest, the two genes were transiently transferred to the fruit, and 20.69% and 23.21% of BP fruits were harvested. After 10 μmol·L-1auxin was infiltrated at low pressure into postharvest fruit, the increase in MdGH3.1 expression occurred earlier than that in MdSAUR36. MdGH3.1 increased the expression of MdSAUR36, but MdSAUR36 did not increase expression of MdGH3.1. Therefore, we suggest that MdGH3.1 acts upstream of MdSAUR36 during BP formation and that these genes induce BP formation by regulating auxin and phenylpropanoid biosynthesis. 展开更多
关键词 APPLE Malusdomestica AUXIN Bitter pit FLAVONOIDS Nitrogen fertilizer Widely targeted metabolomics
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The Importance of Stakeholder Engagement in Progressive Rehabilitation of Large-Scale Open Pit Mines—A Case Study of Lumwana Mine
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作者 Mususu Kosta Mpongo Kaonda Baxter Nsontaulwa 《Journal of Environmental Protection》 2024年第10期963-974,共12页
Mining globally contributes to the growth of many economies of the world. Since its inception, the Zambian mining industry has contributed largely to the country’s economy. The various developments both in technology... Mining globally contributes to the growth of many economies of the world. Since its inception, the Zambian mining industry has contributed largely to the country’s economy. The various developments both in technology and knowledge have contributed to the scale at which mining is being done. Challenges in such a setting arise due to the socio-economic and environmental impacts of mining, which create multidimensional problems. The study investigated the importance of engaging stakeholders in progressive rehabilitation programs for large-scale open pit mines, using a case study of the Lumwana Mine and its host community, Manyama. A qualitative approach was used, and data was collected through one-on-one interviews. A combination of convenient and quota sampling was used to engage with host community leaders, professionals and academicians from various fields and institutions. Results showed that most participants had agreed that stakeholder engagement is important for progressive rehabilitation, but the challenge was that the host community and municipal council representatives were not aware of any progressive rehabilitation efforts at Lumwana Mine. This was attributed to a lack of stakeholder engagement and communication of mitigation progress activities by the Lumwana Mine. Results also revealed that the lack of environmental impact assessment regulations to compel companies to involve stakeholders throughout the entire life of the mine other than just at the pre-mining stage led to a lack of compliance and accountability in rehabilitation. 展开更多
关键词 Progressive Rehabilitation Stakeholder Engagement Open pit Environmental Impact
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Response and assembly of abundant and rare taxa in Zaopei under different combination patterns of Daqu and pit mud:from microbial ecology to Baijiu brewing microecosystem
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作者 Yu Mu Jun Huang +5 位作者 Rongqing Zhou Suyi Zhang Hui Qin Hanlan Tang Qianglin Pan Huifang Tang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1439-1452,共14页
The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Z... The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Zaopei,especially the metabolic function of rare taxa.Here,an experiment on industrial size was designed to assess the effects of 6 combinations(3 kinds of Daqu×2 kinds of PM)on the composition and assembly of different taxa,as well as the flavor profile.The results showed that Zaopei's microbiota was composed of a few abundant taxa and enormous rare taxa,and rare bacterial and abundant fungal subcommunities were significantly affected by combination patterns.The assembly processes of abundant/rare taxa and bacterial/fungal communities were distinct,and environmental changes mediated the balance between stochastic and deterministic processes in rare bacteria assembly.Furthermore,specific combination patterns improved the flavor quality of Zaopei by enhancing the interspecies interaction,which was closely related to rare taxa,especially rare bacteria.These findings highlighted that rare bacteria might be the keystone in involving community interaction and maintaining metabolic function,which provided a scientific foundation for better understanding and regulating the brewing microbiota from the viewpoint of microbial ecology. 展开更多
关键词 Bioaugmented Daqu Artificial pit mud Abundant and rare taxa Community assembly Metabolic function
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Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining
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作者 Jianhua Yan Xiansen Xing +4 位作者 Zhihai Li Weida Ni Liuyuan Zhao Chun Zhu Yuanyuan He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3047-3062,共16页
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ... In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities. 展开更多
关键词 Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope
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Numerical Analysis of Cold-Formed Thin-Walled Steel Short Columns with Pitting Corrosion during Bridge Construction
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作者 Hongzhang Wang Jing Guo +3 位作者 Shanjun Yang Chaoheng Cheng Jing Chen Zhihao Chen 《Structural Durability & Health Monitoring》 EI 2024年第2期181-196,共16页
Pitting corrosion is harmful during bridge construction,which will lead to uneven roughness of steel surfaces and reduce the thickness of steel.Hence,the effect of pitting corrosion on the mechanical properties of col... Pitting corrosion is harmful during bridge construction,which will lead to uneven roughness of steel surfaces and reduce the thickness of steel.Hence,the effect of pitting corrosion on the mechanical properties of cold-formed thin-walled steel stub columns is studied,and the empirical formulas are established through regression fitting to predict the ultimate load of web and flange under pitting corrosion.In detail,the failure modes and load-displacement curves of specimens with different locations,area ratios,and depths are obtained through a large number of non-linear finite element analysis.As for the specimens with pitting corrosion on the web,all the specimens are subject to local buckling failure,and the failure mode will not change with pitting corrosion,but the failure location will change with pitting corrosion location;the size,location,and area ratio of pitting corrosion have little influence on the ultimate load of cold-formed thin-walled steel short columns,but the loss rate of pitting corrosion section area has a greater impact on the ultimate bearing capacity.As for the specimen with flange pitting corrosion,the location and area ratio of pitting corrosion have less influence on the ultimate load of cold-formed thin-walled steel short columns,and the section area loss rate has greater influence on the ultimate bearing capacity;the impact of web pitting corrosion on the ultimate load is greater than that of flange pitting corrosion under the same condition of pitting corrosion section area.The prediction formulas of limit load which are suitable for pitting corrosion of web and flange are established,which can provide a reference for performance evaluation of corroded cold-formed thin-walled steel. 展开更多
关键词 pitting corrosion cold-formed thin-walled steel ultimate load prediction formula short columns
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醋酸靛胭脂混合三明治染色法联合智能分光比色技术结肠镜下Pit pattern分型对结直肠病变的诊断价值
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作者 陆军平 李煜熙 +3 位作者 刘秋贤 李淑明 吴爱华 曲召福 《中国内镜杂志》 2024年第9期61-70,共10页
目的 探讨醋酸靛胭脂混合(AIM)三明治染色法联合智能分光比色技术(FICE)结肠镜下Pit pattern分型对结直肠病变的诊断价值。方法 选择2022年6月-2023年10月该院收治的100例结直肠病变患者作为研究对象,共222处病灶;分别采用普通内镜、FIC... 目的 探讨醋酸靛胭脂混合(AIM)三明治染色法联合智能分光比色技术(FICE)结肠镜下Pit pattern分型对结直肠病变的诊断价值。方法 选择2022年6月-2023年10月该院收治的100例结直肠病变患者作为研究对象,共222处病灶;分别采用普通内镜、FICE和AIM三明治染色+FICE进行检查,并记录Pit pattern分型的检出情况、病理学类型;计算不同模式下Pit pattern分型诊断的敏感度、特异度、阳性预测值(PPV)、阴性预测值(NPV)和准确度,采用Kappa检验评估不同模式下Pit pattern分型诊断与病理学检查的一致性,采用受试者操作特征曲线(ROC curve)评估诊断效能。结果 与普通内镜(74.32%)相比,FICE(92.34%)和AIM三明治染色+FICE (97.30%) Pit pattern分型检出与病理结果符合率更高,且AIM三明治染色+FICE高于FICE,差异均有统计学意义(P <0.05);与普通内镜相比,FICE和AIM三明治染色+FICE诊断结直肠肿瘤性病变的准确度更高,且AIM三明治染色+FICE高于FICE,差异均有统计学意义(P <0.05);与普通内镜相比,FICE和AIM三明治染色+FICE诊断早期结直肠癌的准确度更高,差异均有统计学意义(P <0.05);普通内镜、FICE和AIM三明治染色+FICE预测结直肠肿瘤性病变的曲线下面积(AUC)分别为0.815 (95%CI:0.711~0.859)、0.881 (95%CI:0.752~0.904)和0.933 (95%CI:0.793~0.961);普通内镜、FICE和AIM三明治染色+FICE预测早期结直肠癌的AUC分别为0.850 (95%CI:0.720~0.866)、0.938(95%CI:0.764~0.951)和0.947 (95%CI:0.803~0.972);AIM三明治染色+FICE预测结直肠肿瘤性病变和早期结直肠癌的Youden指数最大,分别为0.955和0.968。结论 AIM三明治染色+FICE下Pit pattern分型诊断结直肠肿瘤性病变和早期结直肠癌的准确度较高,可有效提高内镜的诊治质量。 展开更多
关键词 醋酸靛胭脂混合(AIM)三明治染色 智能分光比色技术(FICE) pit pattern分型 结直肠肿瘤 早期结直肠癌
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Coordinated Mining Procedures of Open Pit Mines Based on River Management
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作者 Baoyu CAO Zhiyong ZHANG +2 位作者 Bo WANG Ruirong DONG Hongjian WANG 《Asian Agricultural Research》 2024年第5期11-14,19,共5页
This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify... This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify a viable approach for ensuring rational and efficient development of open pit mineral resources while simultaneously protecting and restoring the ecological environment of the river.This approach should facilitate the realization of a harmonious symbiosis between mining and river management.The intricate mutual influence relationship between river management and open pit mining is first analyzed in depth,which provides a solid foundation for the subsequent coordination strategy development.In light of the aforementioned considerations,a set of coordination procedures for open pit mining based on river management conditions is proposed.These procedures emphasize the integration of river protection into the overall layout of mining at the planning stage.The implementation of scientific mining schemes,accompanied by rigorous control of the scope and depth of mining operations,has proven to be an effective means of reducing the impact of mining activities on river environments.This approach has also facilitated the achievement of a balance and coordination between mining and river management. 展开更多
关键词 River management Open pit mine Mining procedure Coordinated mining
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JNET分型与Pit Pattern分型对结直肠肿瘤性病变的诊断价值比较研究 被引量:1
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作者 赵倩 杨爱华 +1 位作者 苗向阳 薛会光 《临床医学进展》 2023年第3期3682-3689,共8页
目的:评估并比较窄带成像放大内镜(ME-NBI)下应用JNET分型与Pit pattern分型对结直肠肿瘤性病变的诊断价值,更好地指导内镜下诊治。方法:收集2019.01.01至2021.12.31接受ME-NBI模式结肠镜检查并行病理检查的201例患者,共216处病变,将依... 目的:评估并比较窄带成像放大内镜(ME-NBI)下应用JNET分型与Pit pattern分型对结直肠肿瘤性病变的诊断价值,更好地指导内镜下诊治。方法:收集2019.01.01至2021.12.31接受ME-NBI模式结肠镜检查并行病理检查的201例患者,共216处病变,将依据JNET分型与Pit pattern分型的内镜诊断结果与病理分型结果进行比较。结果:在ME-NBI下JNET分型与Pit pattern分型诊断结直肠肿瘤性病变的敏感度、特异度、阳性预测值、阴性预测值分别为100%、20.83%、90.05%、100%、91.20%和98.96%、54.17%、94.53%、86.67%、93.98%,两者在诊断准确性上差异具有统计学意义(χ2 = 99.116, P < 0.001)。同时,在诊断具有内镜治疗指征的早期结直肠癌时JNET分型、Pit pattern分型的敏感度、特异度、阳性预测值、阴性预测值分别为71.43%、76.05%、46.67%、90.07%、75.00%和81.63%、93.41%、78.43%、94.55%、90.74%,两者在诊断准确性上差异具有统计学意义(χ2 = 14.400, P < 0.001)。结论:ME-NBI下先采用JNET分型可发现更多的肿瘤性病变,再利用Pit pattern提高诊断肿瘤性病变的准确性,提升内镜诊治质量。 展开更多
关键词 结直肠肿瘤 结肠镜检查 窄带成像放大内镜 pit Pattern分型 JNET分型
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Application of open-pit and underground mining technology for residual coal of end slopes 被引量:9
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作者 CHE, Zhaoxue YANG, Hong 《Mining Science and Technology》 EI CAS 2010年第2期266-270,共5页
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining tech... Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized. 展开更多
关键词 integrated open-pit and underground mining end-slope resource recovery economic benefit surface coal mine
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Optimization model of truck flow at open-pit mines and standards for feasibility test 被引量:2
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作者 YingZhang YongZhao QiweiLu WenliXu 《Journal of University of Science and Technology Beijing》 CSCD 2004年第5期389-393,共5页
In order to increase production efficiency at open-pit mines, on the basis oflinear programming, a practical mathematical model for optimizing truck flow was developed, whichimproved the traditional fixed manual sched... In order to increase production efficiency at open-pit mines, on the basis oflinear programming, a practical mathematical model for optimizing truck flow was developed, whichimproved the traditional fixed manual schedule method. The model has advantages from linearprogramming and objective programming, makes most handling points working at full capacity and keepsan optimized ratio between trucks and excavators. For ensuring feasibility of the model inpractical production, four standards for feasibility test were proposed. The model satisfied all thestandards. The application in a large scale open-pit iron mine indicated that the model reduced thenumber of required trucks by 10 percent compared with the fixed manual schedule method. 展开更多
关键词 open-pit mine truck flow linear programming mathematical model FEASIBILITY
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Stability analysis of the sliding process of the west slope in Buzhaoba Open-Pit Mine 被引量:1
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作者 Ning Fang Ji Changsheng Garmondyu E.Crusoe Jr. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期869-875,共7页
To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of th... To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of the 34,600 profile are obtained on the basis of hydrology, geology, and monitoring data.The residual thrust method is utilized to calculate the stability coefficients, which are 1.225 and 1.00 under sound and transfixion conditions, respectively. According to the rock damage and fragmentation and the principle of mechanical parameter degradation, the mechanical models of the slide mass development of the hard and soft rock slopes are established. An integrated model for calculating the slope stability coefficient is built considering water, vibration, and other external factors that pertain to the structural plane damage mechanism and the generating mechanism of the sliding mass. The change curve of the stability coefficient in the slide mass development is obtained from the relevant analyses,and afterwards, the stability control measures are proposed. The analysis results indicate that in the cracking stage of the hard rock, the slope stability coefficient decreases linearly with the increase in the length Lbof the hard rock crack zone. The linear slope is positively correlated to rock cohesion c. In the transfixion stage of the soft rock, the decrease speed of the stability coefficient is positively correlated to the residual strength of the soft rock. When the slope is stable, the stability coefficient is in a quadratic-linear relationship with the decreased height Dh of the side slope and in a linear relationship with anchoring force P. 展开更多
关键词 open-pit mine Side slope Sliding process Aging stability Crack zone
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Monitoring and Assessing Method for Blasting Vibration on Open-pit Slope in Hainan Iron Mine 被引量:3
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作者 SONG Guang ming 1,SHI Xiu zhi 1,ZHOU Zhi guo 1,CHEN Shou ru 1,XIAO Qing hua 2 (1 College of Resources, Environment and Civil Engineering, Central South University of Technology, Changsha 410083, China 2 Production and Technology Departmen 《Journal of Central South University》 SCIE EI CAS 2000年第2期72-74,共3页
A type of velocity sensor CD 1, an auto recording instrument on blasting vibration YBJ 1 and a random signal and vibration analysis system (CRAS) were used to monitor the particle vibration induced by blasting at open... A type of velocity sensor CD 1, an auto recording instrument on blasting vibration YBJ 1 and a random signal and vibration analysis system (CRAS) were used to monitor the particle vibration induced by blasting at open pit slope in Hainan Iron Mine. The attenuating rules of blasting ground vibration on slope were developed. By means of the analysis and calculation of the blasting vibration data at open pit slope and the vertical particle vibration velocity assessment method based on the concept of vibration strength, the empirical attenuating equations which can be used for predicting and estimating the damage of slope were derived. 展开更多
关键词 blasting vibration OPEN pit slope MONITORING ASSESSING
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Charging for the waste dumping of open-pit metal mines 被引量:1
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作者 Yunbing Hou Zhaoxiang Zhang Haifeng Duan Liming Xue 《Journal of University of Science and Technology Beijing》 CSCD 2006年第6期481-485,共5页
Based on the externality theory and the environmental value theory, the hypothesis of charging for waste dumping of open-pit metal mines was put forth. The charging methods were designed according to the characteristi... Based on the externality theory and the environmental value theory, the hypothesis of charging for waste dumping of open-pit metal mines was put forth. The charging methods were designed according to the characteristics of waste dumping of openpit metal mines, including charging based on the dumping amount of the total waste, multi-charging factors, exceeding standard punishment charging, and so on. The main charging parameter is based on the dumping area rather than the total amount of waste dumping. The charging model of waste dumping of open-pit mines was formulated, and the charging rate was divided into two parts, i.e., the standard charging rate and the differential charging rate. The standard charging rate was derived using the equilibrium dynamic model, whereas the differential one was obtained by establishing the fuzzy synthesized evaluation model. 展开更多
关键词 open-pit metal mine waste dumping charging pattern basic charging rate differential charging rate
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Cut slope reinforcement technique in open-pit mines 被引量:3
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作者 YongtaoGao JianboSun +1 位作者 ShunchuanWu AibingJin 《Journal of University of Science and Technology Beijing》 CSCD 2004年第4期289-292,共4页
The design and practice in supporting the cut slope of an open-pit mine wereintroduced, in which the high pressure grouting method was used in reinforcing the weak formation inthe slopes. Based on a detailed geologica... The design and practice in supporting the cut slope of an open-pit mine wereintroduced, in which the high pressure grouting method was used in reinforcing the weak formation inthe slopes. Based on a detailed geological survey of the slope, a theoretical analysis was carriedout, and the design parameters were proposed, where the Tresca or Mohr-Coulomb yield criteria wasemployed. A patent technology, named 'Technology of high pressure and multiple grouting in differentlevels within a single hole', was employed in the construction. Anchor bars were also installed asgrouting proceeds. This method combines anchoring and grouting comprehensively and was foundsuccessful in practice. 展开更多
关键词 mining engineering open-pit slope weak formation SUPPORTING high pressuregrouting
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