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Determination of Monitoring Control Value for Concrete Gravity Dam Spatial Deformation Based on POT Model
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作者 Zhiwen Xie Tiantang Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2119-2135,共17页
Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring c... Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring control value only considers the single measuring point.In order to overcome the limitation,this paper presents a new method to determine the monitoring control value for concrete gravity dam based on the deformations of multi-measuring points.A dam’s comprehensive deformation displacement is determined by the measured values at different measuring points on the positive inverted vertical line and the corresponding weight of eachmeasuring point.The projection pursuit method(PPM)combined with the grey wolf optimization(GWO)algorithm is used to determine the weight of each measuring point according to the spatial correlation distribution characteristics of dam deformation.The peaks over threshold(POT)model based on the extreme value theory is adopted to determine the monitoring control value with the obtained dam comprehensive deformation displacement.In addition,the POTmodel is improved with the automatic threshold determinationmethod based on the 3σcriterion in probability theory and the GWO algorithm,which can avoid subjectivity and randomness in determining the threshold.The results of the engineering application show the feasibility and applicability of the proposed method. 展开更多
关键词 Concrete gravity dam DEFORMATION monitoring control value PPM GWO POT
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The value of abnormal muscle response monitoring during microvascular decomprssion surgery for hemifacial spasm
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作者 应婷婷 《外科研究与新技术》 2011年第3期218-218,共1页
Objective Abnormal muscle response (AMR) to the electrical stimulation of a branch of facial nerve is a specific electrophysiological feature of primary hemifacial spasm (HFS) . Although the correlation between intrao... Objective Abnormal muscle response (AMR) to the electrical stimulation of a branch of facial nerve is a specific electrophysiological feature of primary hemifacial spasm (HFS) . Although the correlation between intraoperative AMR findings and postoperative results in patients with HFS were investigated before, 展开更多
关键词 AMR HFS The value of abnormal muscle response monitoring during microvascular decomprssion surgery for hemifacial spasm MVD
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CLINICAL VALUE OF URINARY AND SERUM PSEUDOURIDINE IN DIAGNOSIS AND MONITORING OF PRIMARY LIVER CANCER 被引量:1
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作者 屠振兴 许圣献 吴孟超 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第3期46-50,共5页
Urinary and serum pseudouridine concentrations were determined by high-performance liquid chromatography in 80 patients with primary liver cancer, 32 with benign space occupying lesions of the liver, 42 with liver cir... Urinary and serum pseudouridine concentrations were determined by high-performance liquid chromatography in 80 patients with primary liver cancer, 32 with benign space occupying lesions of the liver, 42 with liver cirrhosis and 40 healthy subjects. Their mean urinary and serum pseudouridine levels were 39.2=11.5 nmol / /μmol creatinine and 3.4 ± 1.3 μmol / L, 24.5 = 5.4 nmol / μmol creatinine and 2.5 = 0.5 μmol / L, 22.8 ± 7.8 nmol / μmol creatinine and 2.3 = 0.4 μmol / L, 26.4 ± 4.6 nmol / μmol creatinine and 2.3 = 0.4 μmol / L, respectively. Exceeding the mean plus 2SD of pseudouridine of healthy control was considered as positive value for the diagnosis of primary liver cancer. Thus the positivity of urinary and serum pseudouridine in hepatoma was 71.3% and 70.0%, respectively. The positive rate of combined pseudouridine and alpha-fetoprotein assay was 91.3% in patients with hepatoma. Besides, pseudouridine levels could elevate before positive localization and reduce to normal levels after tumor resection. The results showed that the determination of pseudouridine is of clinical significance in the diagnosis and monitoring of primary liver cancer. 展开更多
关键词 CLINICAL value OF URINARY AND SERUM PSEUDOURIDINE IN DIAGNOSIS AND monitoring OF PRIMARY LIVER CANCER than
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Appraisal of arid land status:a holistic assessment pertains to bio-physical indicators and ecosystem values
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作者 Manish Mathur S.Sundaramoorthy 《Ecological Processes》 SCIE EI 2018年第1期487-501,共15页
Background:Appraisal of arid land status is very crucial one to know the extent and factors associated with their degradation.Previous studies from arid regions are mostly qualitative in nature(indicator assessment li... Background:Appraisal of arid land status is very crucial one to know the extent and factors associated with their degradation.Previous studies from arid regions are mostly qualitative in nature(indicator assessment like good,moderate,severe,and very severe)and generally overlooked the significance of temporal fluctuation.Methods:In this study,the temporal status of 12 Indian arid lands was accessed by using a new integrated approach that includes attributes like relative converge score(RCS),herbaceous component score(HCS),soil quality indexModified(SQI),ecosystem monitoring value(EMV),and a modified bare patch index.From each land,data were collected during three seasonal events(pulse,inter-pulse,and non-pulse),and thus,status was evaluated with 36 observations.Data were analyzed by using frequency distribution,principal component analysis(PCA),student t test,and regression technique.Results:RCS and HCS were recorded minimum(0.005,0.65)during non-pulse event and maximum(0.36,1.79)during pulse event respectively.With this approach,multi-directional temporal status of lands identified that were grouped into lower(7),moderate(14),high(12),and very high(3)quality lands.Conclusion:This integrated study suggested that in arid regions,although rainfall triggers plant community composition,however,sole utilization of this parameter is unable to portray the true status of lands,and other physical(soil)and biotic(livestock and other anthropogenic)parameters are equally important and influential during other events. 展开更多
关键词 Vegetation status Relative coverage score Soil quality Land status Ecosystem monitoring value
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Influences of the Three Gorges Project on seismic activities in the reservoir area 被引量:11
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作者 Yun-Sheng Yao Qiu-Liang Wang +5 位作者 Wu-Lin Liao Li-Fen Zhang Jun-Hua Chen Jing-Gang Li Li Yuan Yan-Nan Zhao 《Science Bulletin》 SCIE EI CAS CSCD 2017年第15期1089-1098,共10页
Reservoir-induced earthquakes related with the construction of the Three Gorges Project have attracted great concerns of the public. Since the first water impoundment on May 25, 2003, a number of earthquakes have occu... Reservoir-induced earthquakes related with the construction of the Three Gorges Project have attracted great concerns of the public. Since the first water impoundment on May 25, 2003, a number of earthquakes have occurred during the water storage stages, in which the largest was the Badong M5.1 earthquake on December 16, 2013. In this paper, the relationships between seismic activities, b value, seismic parameters, and reservoir water level fluctuations are studied. In addition, based on the digital seismic waveform data obtained since 2000, the focal depth changes and focal mechanism characteristics before and after the water impoundment are studied as well. These provide us important information to understand the earthquake mechanisms. The results show that these earthquakes are typical reservoir-induced earthquakes, which are closely related to water infiltration, pore pressure, and water level fluctuations.The majority of the micro and small earthquakes are caused by karst collapse, mine collapse, bank reformation, superficial unloading, and so on. The larger earthquakes are related to the fault structures to some extent. Due to the persistent effects of water impoundment on the seismic and geological environments around the reservoir and water infiltration into the rocks, the influences on the crustal deformation field, gravity field, seepage field, and fault medium-softening action may vary gradually from a higher strength to a weaker one. Therefore, it is possible that small earthquakes and few medium earthquakes(M≤5.5) will occur in the reservoir area in the future. 展开更多
关键词 Three Gorges Project Earthquake monitoring network Reservoir-induced earthquake Seismic activity b value Focal mechanism
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