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基于开源软件的校园网监控体系 被引量:6
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作者 冷永平 白海 《三峡大学学报(自然科学版)》 CAS 2009年第4期102-105,共4页
快速发现网络故障、定位故障点,需要对接入设备进行管理,了解网络的运行情况,包括端口数据流量、设备运行性能和状况等各项指标.通过开源软件设计了一种利用遵循SNMP协议的高效监控系统,来获取校园网络节点状态信息的有效方法.并将校园... 快速发现网络故障、定位故障点,需要对接入设备进行管理,了解网络的运行情况,包括端口数据流量、设备运行性能和状况等各项指标.通过开源软件设计了一种利用遵循SNMP协议的高效监控系统,来获取校园网络节点状态信息的有效方法.并将校园网接入设备状况以非常直观的形式显示出来,以便有效地提高网络管理水平. 展开更多
关键词 SNMP MID MRTG PERL
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监控量测在大官市隧道中的应用 被引量:3
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作者 张铁柱 刘建彪 《云南交通科技》 2002年第5期67-74,共8页
本文从监控量测的必要性、理论基础、实施方法。
关键词 大官市隧道 监量测 公路隧道
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Annual Monitoring and Evaluation of the Grades of Arable Land Quality——Taking Lingchuan County as an Example 被引量:2
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作者 全坚 谭咪 《Agricultural Science & Technology》 CAS 2017年第6期1112-1119,共8页
With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and developm... With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and development trends of arable land quality. It is also an important measure for protecting the quality of arable land. in the present study, the distribution and changes of arable lands of different gradient types and grades in Lingchuan County, Guangxi Zhuang Autonomous Region in 2015 were monitored and evaluated, to analyze the trends and reasons for the changes in the quality and productivity of arable lands, and to provide references for dynamic monitoring of the quality of arable land. 展开更多
关键词 Arable land grades MONITORING Evaluation Lingchuan County
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Research of Dynamic Monitoring on Arable Land Quality
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作者 何江华 《Agricultural Science & Technology》 CAS 2014年第12期2278-2280,共3页
In China with such a large population and few land, the problem of arable land is particularly prominent. While the amount of arable land per capita is small, the quality of arable land is declining. Compared with the... In China with such a large population and few land, the problem of arable land is particularly prominent. While the amount of arable land per capita is small, the quality of arable land is declining. Compared with the decreasing arable land, the decline in the quality of arable land is invisible and hard to be detected. But the impact is no less than the amount of arable land reduced, and ~;hanges in the quality of arable land pose a serious threat to ecological environment and socio- economic development. Against the background of high-intensity development and the amount of arable land decreasing, the research of monitoring of arable land quality is of great realistic significance. 展开更多
关键词 Standard-plot Arable Land Quality MONITORING
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Real-time Monitoring Scheme of Soil Moisture Content in Paddy Field
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作者 贾宏伟 胡荣祥 刘威琼 《Agricultural Science & Technology》 CAS 2013年第11期1679-1682,共4页
The monitoring of soil moisture content in paddy field is one of important parts and contents of regional soil moisture monitoring. But a good monitoring scheme hasn’t been established. A real-time monitoring scheme ... The monitoring of soil moisture content in paddy field is one of important parts and contents of regional soil moisture monitoring. But a good monitoring scheme hasn’t been established. A real-time monitoring scheme of soil moisture content in paddy field was put forward from two key links of soil moisture content monitoring and field water-layer monitoring. This scheme could meet the alternative monitoring requirements of soil moisture content in water layer and none-water layer. It had a good maneuverability and could provide references for practical work. 展开更多
关键词 Paddy field Moisture content Soil moisture content Field water-layer Real-time monitoring
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An Approach to Unsupervised Character Classification Based on Similarity Measure in Fuzzy Model
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作者 卢达 钱忆平 +1 位作者 谢铭培 浦炜 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期370-376,共7页
This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first ... This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first split into eight typographical categories. The classification scheme uses pattern matching to classify the characters in each category into a set of fuzzy prototypes based on a nonlinear weighted similarity function. The fuzzy unsupervised character classification, which is natural in the repre... 展开更多
关键词 fuzzy model weighted fuzzy similarity measure unsupervised character classification matching algorithm classification hierarchy
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Research on Precise Trigonometric Leveling in Place of First Order Leveling 被引量:7
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作者 ZHANG Zhenglu ZHANG Kun +1 位作者 DENG Yong LUO Changlin 《Geo-Spatial Information Science》 2005年第4期235-239,共5页
Through the analysis of the principle, error sources and precision of trigonometric leveling, this paper points out the key problems about first order leveling replaced by trigonometric leveling; and for the first tim... Through the analysis of the principle, error sources and precision of trigonometric leveling, this paper points out the key problems about first order leveling replaced by trigonometric leveling; and for the first time puts forward that, in some given conditions, it is not only feasible but also valuable to replace first order leveling by precise trigonometric leveling, and proves it by experimentation as well. The content and conclusion of this paper have consulting significance and practicable value for our setting down relational criterion and production practice. 展开更多
关键词 electronic distance measurements trigonometric leveling first order leveling surveying for deformation monitoring
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Monitoring Seasonal Variations of Ionospheric TEC Using GPS Measurements 被引量:3
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作者 CAI Changsheng 《Geo-Spatial Information Science》 2007年第2期96-99,共4页
The regional ionospheric model is adopted to determine satellite-plus-receiver differential delay. The satellite-plus-receiver differential delay is estimated as constant values for each day. Dual-frequency GPS pseudo... The regional ionospheric model is adopted to determine satellite-plus-receiver differential delay. The satellite-plus-receiver differential delay is estimated as constant values for each day. Dual-frequency GPS pseudo-ranges observables are used to compute vertical TEC (VTEC). All the monthly mean VTEC profiles are represented by graphs using GPS data of the Beijing IGS site between 2000 and 2004. The monthly averaged values and amplitudes of VTEC are also represented by graphs. The results indicate that the VTEC has seasonal dependency. The monthly averaged values and amplitudes of VTEC in 2000 are about 2 times larger than that in 2004. The maximum VTEC values are observed in March and April, while the minimum VTEC values are observed in December. The seasonal variations trend is found to be similar after polynomial fitting between 2000 and 2004. 展开更多
关键词 GPS differential delay IONOSPHERE TEC
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Land Quality Assessment and Monitoring:The Next Challenge for Soil Science 被引量:33
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作者 H.ESWARAN J.KIMBLE 《Pedosphere》 SCIE CAS CSCD 2003年第1期1-10,共10页
Sustainable land management (SLM) is the key to harmonizing environmental and ecological concernsof society with the economic realities of producing adequate food and fiber of high quality and ensuring abasic minimal ... Sustainable land management (SLM) is the key to harmonizing environmental and ecological concernsof society with the economic realities of producing adequate food and fiber of high quality and ensuring abasic minimal quality of life. The aim of SLM is to maintain the integrity of the biophysical land resourcebase, but it can only be realized if land users understand the impacts of land management options on theirlands but also on other off-site areas and can optimize the socioeconomic and environmental benefits of theirchoice. To facilitate this, the contribution of soil survey organizations would be through the assessment andmonitoring of land quality. Land quality is a measure of the ability of land to perform specific functions and isderived by an integration of soil survey information with other environmental, and if necessary, socioeconomicinformation. The desired reliability influences the operational scale of the assessment. Such an assessmentwould assist in: 1) locating homologous areas for research sites or for transferring technologies; 2) providingthe geographic basis for systems analysis (e.g. by modeling); 3) serving as a basis for local, national andglobal resource assessment and monitoring; 4) providing an ecosystem context for land use, assessments oftemporal and spatial variability, and impact of human interventions; 5) serving as a framework for moredetailed assessment for all levels of interest; and 6) evaluating global issues such as food security, impacts ofclimate change, biodiversity monitoring, and addressing desertification.Based on an evaluation of the progress made in soil resource inventories and considering the demandsof the environment focused world, the paper considers the need for countries to mount such a program. Theauthors believe that this is the next demand of soil science and that we can fulfill our social contract byperiodically providing such information on the state of a nation's land resource. 展开更多
关键词 degradation land quality monitoring of soils sustainable landmanagement
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Solubility and metastable zone width measurement of 3,4-bis (3-nitrofurazan-4-yl) furoxan (DNTF) in ethanol + water 被引量:9
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作者 Lizhen Chen Liang Song +1 位作者 Guanchao Lan Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第5期646-651,共6页
The solubility and supersolubility of 3,4-bis(3-nitrofurazan-4-yl)furoxan(DNTF) in ethanol + water at different operation were determined by laser monitoring system under atmospheric pressure to study the metastable z... The solubility and supersolubility of 3,4-bis(3-nitrofurazan-4-yl)furoxan(DNTF) in ethanol + water at different operation were determined by laser monitoring system under atmospheric pressure to study the metastable zone width(MSZW). The modified Apelblat equation was adopted to correlate the experimental solubility data, and the correlation result showed perfect consistent with the experimental data. The standard dissolution enthalpy, standard dissolution entropy and Gibbs energy were calculated according to the experimental solubility data. The effect of the cooling rate, stirring rate, temperature and the concentration of ethanol + water on the MSZW was studied. It was found that the MSZW of DNTF increased with the increasing cooling rate, decreasing temperature, decreasing stirring rate and decreasing ratio of water. And the apparent nucleation order of DNTF in ethanol + water was calculated by the relationship between the cooling rate and the MSZW. 展开更多
关键词 3 4-Bis(3-nitrofurazan-4-yl)furoxan SOLUBILITY Metastable zone width Apparent nucleation order
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A new process monitoring method based on noisy time structure independent component analysis 被引量:2
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作者 蔡连芳 田学民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期162-172,共11页
Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the advers... Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the adverse effects of the measurement noises. In this paper, a new process monitoring approach based on noisy time structure ICA(Noisy TSICA) is proposed to solve such problem. A Noisy TSICA algorithm which can consider the measurement noises explicitly is firstly developed to estimate the mixing matrix and extract the independent components(ICs). Subsequently, a monitoring statistic is built to detect process faults on the basis of the recursive kurtosis estimations of the dominant ICs. Lastly, a contribution plot for the monitoring statistic is constructed to identify the fault variables based on the sensitivity analysis. Simulation studies on the continuous stirred tank reactor system demonstrate that the proposed Noisy TSICA-based monitoring method outperforms the conventional Fast ICA-based monitoring method. 展开更多
关键词 Process monitoring Independent component analysis Measurement noises KURTOSIS Mixing matrix Contribution plot Sensitivity analysis
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广州地铁一号线东山口站深基坑开挖与支护技术
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作者 陈建军 《铁道建筑》 北大核心 2000年第7期5-9,共5页
介绍广州地铁一号线东山口站在地质条件恶劣、周边环境恶劣和施工条件极为困难的情况下 ,选择合理的支护型式和开挖方式 ,安全快速地完成深基坑的开挖。
关键词 深基坑 支护技术 开挖 爆破 地铁车站
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Settlement Prediction for Buildings Surrounding Foundation Pits Based on a Stationary Auto-regression Model 被引量:3
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作者 TIAN Lin-ya HUA Xi-sheng 《Journal of China University of Mining and Technology》 EI 2007年第1期78-81,共4页
To ensure the safety of buildings surrounding foundation pits, a study was made on a settlement monitoring and trend prediction method. A statistical testing method for analyzing the stability of a settlement monitori... To ensure the safety of buildings surrounding foundation pits, a study was made on a settlement monitoring and trend prediction method. A statistical testing method for analyzing the stability of a settlement monitoring datum has been discussed. According to a comprehensive survey, data of 16 stages at operating control point, were verified by a standard t test to determine the stability of the operating control point. A stationary auto-regression model, AR(p), used for the observation point settlement prediction has been investigated. Given the 16 stages of the settlement data at an observation point, the applicability of this model was analyzed. Settlement of last four stages was predicted using the stationary auto-regression model AR (1); the maximum difference between predicted and measured values was 0.6 mm, indicating good prediction results of the model. Hence, this model can be applied to settlement predictions for buildings surrounding foundation pits. 展开更多
关键词 foundation pit BUILDING settlement monitoring datum stability stationary auto-regression model settlement prediction
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A Novel Systematic Method of Quality Monitoring and Prediction Based on FDA and Kernel Regression 被引量:2
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作者 张曦 马思乐 +2 位作者 阎威武 赵旭 邵惠鹤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期427-436,共10页
A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der ... A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der normal condition, then kernel regression is further used for quality prediction and estimation. If faults have oc-curred, the contribution plot in the fault feature direction is used for fault diagnosis. The proposed method can ef-fectively detect the fault and has better ability to predict the response variables than principle component regression (PCR) and partial least squares (PLS). Application results to the industrial fluid catalytic cracking unit (FCCU) show the effectiveness of the proposed method. 展开更多
关键词 quality monitori-ng -quality prediction Fisher discriminant analysis kernel regression fluid catalyticcracking unit
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Determination of volumetric changes at an underground stone mine: a photogrammetry case study 被引量:2
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作者 Slaker Brent Westman Erik +1 位作者 Ellenberger John Murphy Michael 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第1期149-154,共6页
Photogrammetry, as a tool for monitoring underground mine deformation, is an alternative to traditional point measurement devices, and may be capable of accurate measurements in situations where technolo- gies such as... Photogrammetry, as a tool for monitoring underground mine deformation, is an alternative to traditional point measurement devices, and may be capable of accurate measurements in situations where technolo- gies such as laser scanning are unsuited, undesired, or cost-prohibitive. An underground limestone mine in Ohio is used as a test case for monitoring of structurally unstable pillars. Seven pillars were pho- tographed over in a 63 day period, punctuated by four visits. Using photogrammetry, point clouds of the mine geometry were obtained and triangulation surfaces were generated to determine volumes of change over time. Pillar spaUing in the range of 0.29-4.03 m3 of rock on individual rib faces was detected. Isolated incidents of rock expansion prior to failure, and the isolated failure of a weak shale band were also observed. Much of the pillars remained unchanged during the monitoring period, which is indicative of proper alignment in the triangulated surfaces. The photographs of some ribs were of either too poor quality or had insufficient overlap, and were not included. However, photogrammetry was successfully aonlied to multiole ribs in auantifving the oillar geometrv change over time. 展开更多
关键词 PhotogrammetryLimestoneUnderground miningDisplacementMonitoring
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Relationship between impact of dose distribution and energy of radioactive ray for metal contraceptive ring 被引量:2
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作者 Jianwen Zhang Huiqun Luo Bo Yang Haowen Pang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第8期482-485,共4页
Objective: We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods: The SI Virtual Water Phantom was used to monitor medium of do... Objective: We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods: The SI Virtual Water Phantom was used to monitor medium of dose. PTW ionization chamber was used to detect the dose. AP-PA (10 cmx 10 cm) and SAD technique were adopted. Monitoring dose of different locations with different energy of radioactive ray in AP and PA respectively with and without contraceptive ring, repeated 5 times. Results: Dose of with contraceptive ring was lower than that of without contraceptive ring in AP 6 MV- X-ray (P 〈 0.05), while in PA was no obvious difference (P 〉 0.05). Dose of except for the center was higher than that of without contraceptive ring in AP and PA 15 MV-X-ray (P 〈 0.05). For locations, doses of the upper, the left and right were higher than that of the center in AP 6 MV-X-ray (P 〈 0.05), while in PA was lower (P 〉 0.05). In AP and PA 15 MV-X-ray, doses of the upper, the left and right was higher than that of the center (P 〈 0.05). Conclusion: Metallic contraceptive ring would effect the dose distribution of radioactive ray, but influence degree related to locations of contraceptive ring and energy of radioactive ray. 展开更多
关键词 contraceptive ring RADIOTHERAPY DOSE
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Does deep sedation impact the results of 48 hours catheterless pH testing? 被引量:1
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作者 Vineet Korrapati Jay P Babich +3 位作者 Anil Balani James H Grendell, Kavita R Kongara Anil Balani James H Grendell Kavita R Kongara 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第10期1304-1307,共4页
AIM: To study a cohort of patients undergoing 48 h Bravo pH testing receiving deep sedation with propofol. METHODS: We retrospectively reviewed the charts of 197 patients (81 male, 116 female) who underwent Bravo ... AIM: To study a cohort of patients undergoing 48 h Bravo pH testing receiving deep sedation with propofol. METHODS: We retrospectively reviewed the charts of 197 patients (81 male, 116 female) who underwent Bravo esophageal pH monitoring from July 2003 to January 2008. All patients underwent Bravo pH probe placement via esophagogastroduodenoscopy (EGD) and received propofol for sedation. Patients on a proton pump inhibitor (89 patients) were excluded. Acid reflux variables measured included the total, upright, and supine fractions of time at pH 〈 4 and DeMeester score, and were compared between day I and day 2. RESULTS: Of the 108 patients that were included in the study, the most common indication for Bravo pH monitoring was heartburn, with chest pain being the second most common. A signed rank test revealed no statistically significant difference between day I and day 2 reflux episodes. CONCLUSION: Patients who received propofol for sedation for EGD with Bravo pH capsule placement did not experience any significant difference in reflux episodes from day 1 to day 2. 展开更多
关键词 ESOPHAGUS Bravo study PROPOFOL pH cap-sule Gastroesophageal reflux disease
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Statistical Monitoring of Chemical Processes Based on Sensitive Kernel Principal Components 被引量:10
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作者 JIANG Qingchao YAN Xuefeng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期633-643,共11页
The kernel principal component analysis (KPCA) method employs the first several kernel principal components (KPCs), which indicate the most variance information of normal observations for process monitoring, but m... The kernel principal component analysis (KPCA) method employs the first several kernel principal components (KPCs), which indicate the most variance information of normal observations for process monitoring, but may not reflect the fault information. In this study, sensitive kernel principal component analysis (SKPCA) is proposed to improve process monitoring performance, i.e., to deal with the discordance of T2 statistic and squared prediction error SVE statistic and reduce missed detection rates. T2 statistic can be used to measure the variation di rectly along each KPC and analyze the detection performance as well as capture the most useful information in a process. With the calculation of the change rate of T2 statistic along each KPC, SKPCA selects the sensitive kernel principal components for process monitoring. A simulated simple system and Tennessee Eastman process are employed to demonstrate the efficiency of SKPCA on online monitoring. The results indicate that the monitoring performance is improved significantly. 展开更多
关键词 statistical process monitoring kernel principal component analysis sensitive kernel principal compo-nent Tennessee Eastman process
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Design and validation of wireless acceleration sensor network for structural health monitoring 被引量:3
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作者 喻言 Ou Jinping 《High Technology Letters》 EI CAS 2006年第4期358-362,共5页
A wireless sensor network is proposed to monitor the acceleration of structures for the purpose of structural health monitoring of civil engineering structures. Using commercially available parts, several modules are ... A wireless sensor network is proposed to monitor the acceleration of structures for the purpose of structural health monitoring of civil engineering structures. Using commercially available parts, several modules are constructed and integrated into complete wireless sensors and base stations. The communication protocol is designed and the fusion arithmetic of the temperature and acceleration is embedded in the wireless sensor node so that the measured acceleration values are more accurate. Measures are adopted to finish energy optimization, which is an important issue for a wireless sensor network. The test is perfonned on an offshore platform model, and the experimental results are given to show the feasibility of the designed wireless sensor network . 展开更多
关键词 wireless sensor network structural health monitoring wireless sensor ACCELERATION energy optimization
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Intensity Retrieved from Public Monitoring Video——Cases from the May 12,2008,Wenchuan Earthquake 被引量:1
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作者 Yang Xiaolin Wu Zhongliang Xia Min 《Earthquake Research in China》 2008年第3期229-236,共8页
Macroseismic investigation is presented with a new potential means of investigation in the "digital age". In this paper we studied several cases in the May 12, 2008, Wenchuan M_S8.0 earthquake with a view to... Macroseismic investigation is presented with a new potential means of investigation in the "digital age". In this paper we studied several cases in the May 12, 2008, Wenchuan M_S8.0 earthquake with a view to exploring the feasibility of retrieving intensity, or even strong ground motion parameters, from public monitoring video which was originally deployed for security purposes. We used public monitoring video records from 44 sites across the meizoseismal region and its surroundings to estimate the intensity. By using the video from a bank in Dujiangyan, Sichuan Province and making the simple assumption that ground vibration is in the form of a propagating harmonic wave, we estimated that the local ground motion acceleration was 0.14g. 展开更多
关键词 INTENSITY Parameters of strong ground motion Public monitoring video macroseismology
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