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Evaluation of Trace Elements in the Soil of Typical Peach Orchards in Zunyi City
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作者 Wenzhao LI Xiong YAN +5 位作者 Jun CHENG Xingyong WANG Changling SUI Xiangchun ZHANG Zhuang ZHAO Peng ZHOU 《Agricultural Biotechnology》 2024年第1期17-19,共3页
[Objectives]This study was conducted to clarify the enrichment and paucity of trace elements in the soil environment of peach orchards in Zunyi City,and to provide reference for supplementary application of microeleme... [Objectives]This study was conducted to clarify the enrichment and paucity of trace elements in the soil environment of peach orchards in Zunyi City,and to provide reference for supplementary application of microelement fertilizers and high-quality peach production in peach orchards.[Methods]Taking the soil of three typical peach orchards(Taoli Renjia peach orchard,Pengrui peach orchard and Taohuadao peach orchard)in Shenxi Town,Honghuagang District,Zunyi City as the research object,the contents of trace elements in soil were analyzed through field sampling and indoor determination of trace elements.[Results]The effective contents of trace elements in the soil of peach orchard bases in the study area were at a medium level,and the soil of the peach orchards was rich in available Fe and Se.The contents of available Cu,Mo and Mn were relatively rich.The contents of available B were not high overall.The contents of available Zn were at a moderate to low level overall.The soil of Taoli Renjia peach orchard was relatively rich in trace elements.[Conclusions]The research results can provide a scientific basis for the production of high-quality crispy peaches in peach orchards. 展开更多
关键词 Zunyi Soil in peach orchard Trace elements evaluation
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Discussion on Statistical Monitoring and Evaluation of High-Quality Development of County Economy
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作者 Lifen Chen 《Proceedings of Business and Economic Studies》 2023年第6期92-97,共6页
The county economy serves as the fundamental unit in China’s economic development and construction.There exists a significant correlation between the quality and level of county economic development and the overall e... The county economy serves as the fundamental unit in China’s economic development and construction.There exists a significant correlation between the quality and level of county economic development and the overall economic construction level of the country.In recent years,China’s economy has experienced rapid growth,contributing to an improved living environment and substantial economic income for its citizens.However,this progress has also brought to light certain issues,such as an unbalanced industrial structure and inefficient resource utilization,leading to problems such as low efficiency and severe environmental pollution.Therefore,it becomes imperative to enhance the statistical monitoring and evaluation of high-quality county economic development.This approach aims to gather insights into the development status of the county economy and provide essential data support for decision-making in county economic development.Consequently,this paper proposes development suggestions for the statistical monitoring and evaluation of high-quality county economic development,serving as a crucial starting point for future initiatives. 展开更多
关键词 County economy High-quality development Statistical monitoring and evaluation
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Analysis and evaluation of enterprise risk management capability elements 被引量:1
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作者 Liu, Weiwei Wang, Jun Shi, Chunsheng 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期77-81,共5页
Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are... Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are constructed. The risk management capability consists of four aspects, i.e. risk identification capability, risk assessment capability, risk planning capability and risk control capability. Risk identification and assessment capabilities reflect the level of enterprises on finding and analyzing risks efficiently, while risk planning and control capabilities reflect the level of enterprises on resolving risks effectively. Each of capabilities is then further divided into more detailed elements based on the characteristics of enterprise development for a quantitative analysis of enterprise risk management capability. The approach adopted is a quantitative technique based on the use of fuzzy comprehensive evaluation. Finally, a case is pulled in to illustrate the feasibility of the method from an empirical perspective. This study is expected to be helpful for enterprises in cultivating their core capabilities. 展开更多
关键词 evaluation index system capability elements risk management fuzzy comprehensive evaluation
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Safety evaluation of replacement reinforcement quality in abutment contact zones of ultra-high arch dam in first impoundment period based on prototype monitoring 被引量:2
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作者 Bo HU Zhong-ru WU +2 位作者 Guan-biao LIU Bin ZHAO Bo XU 《Water Science and Engineering》 EI CAS 2012年第2期210-218,共9页
Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact z... Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact zones of the Xiaowan ultra-high arch dam. The principles of monitoring layout and design are introduced in detail. Prototype monitoring shows that the increment of the interfacial compressive stress is much larger in the impoundment stage than in the regulating stage. The water pressure and time-effect are two main factors affeeting the interfacial stress. The time-effect is the key factor in the initial impoundment stage, and the water pressure is the key factor after impoundment. The contact properties are significantly improved by grouting. This study shows that there are three typical stages in the joint opening hydrographs, namely the compression stage, opening stage, and stable stage. There is a nonlinear relationship between the joint opening and temperature, which can be well described by the S-function. In conclusion, the reinforcement effect is satisfying, and the abutment is safe. 展开更多
关键词 ultra-high arch dam prototype monitoring compressive stress joint opening safety evaluation
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Evaluation of GSMaP Daily Rainfall Satellite Data for Flood Monitoring: Case Study—Kyushu Japan 被引量:3
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作者 Martiwi Diah Setiawati Fusanori Miura 《Journal of Geoscience and Environment Protection》 2016年第12期101-117,共17页
In this paper, the Global Satellite Mapping of Precipitation Moving Vector with Kalman filter (GSMaP_MVK) was evaluated and corrected at daily time scales with a spatial resolution of 0.1°;latitude/longitude. The... In this paper, the Global Satellite Mapping of Precipitation Moving Vector with Kalman filter (GSMaP_MVK) was evaluated and corrected at daily time scales with a spatial resolution of 0.1°;latitude/longitude. The reference data came from thirty-four rain gauges on Kyushu Island, Japan. This study focused on the GSMaP_MVK’s ability to detect heavy rainfall patterns that may lead to flooding. Statistical analysis was used to evaluate the GSMaP_MVK data both quantitatively and qualitatively. The statistical analysis included the relative bias (B), the mean error (E), the Nash-Sutcliffe coefficient (CNS), the Root Mean Square Error (RMSE) and the correlation coefficient (r). In addition, Generalized Additive Models (GAMs) were used to conduct GSMaP_MVK data correction. The results of these analyses indicate that GSMaP_MVK data have lower values than observed data and may be significantly underestimated during heavy rainfall. By applying GAM to bias correction, GSMaP_MVK’s ability to detect heavy rainfall was improved. In addition, GAM for bias correction could effectively be applied for significant underestimates of GSMaP_ MVK (i.e., bias of more than 55%). GAM is a new approach to predict rainfall amount for flood and landslide monitoring of satellite base precipitation, especially in areas where rain gauge data are limited. 展开更多
关键词 evaluation GSMaP_MVK Flood monitoring KYUSHU
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Stability evaluation for steep bank slope with microseismic monitoring in Three Gorges Reservoir area 被引量:1
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作者 XIE Qing-ming LONG Kui +7 位作者 LI Zi-mu CHEN Li-chuan LIU Hong XU Hong HE Fei LIANG Dan XIANG Xue-kun MA Qiang 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1588-1601,共14页
Rock slide is one of the common geohazard in the Three Gorges Reservoir area, and it affects the shipping of the Yangtze River and the safety of people living on the banks. In order to investigate the internal fractur... Rock slide is one of the common geohazard in the Three Gorges Reservoir area, and it affects the shipping of the Yangtze River and the safety of people living on the banks. In order to investigate the internal fracturing mechanism of rock mass, distributed microseismic monitoring network was arranged with 15 three component geophones(3C geophones), deployed at borehole and out of the sliding mass in the unstable Dulong slope. Stein Unbiased Risk Estimation(SURE) method was used to noise suppression for the microseismic record, and decomposition parameters of the Continuous Wavelet Transform(CWT) were determined with maximum energy of correlation coefficient(MECC) method. The signal-to-noise ratio was tripled after the process, and source parameters are obtained with full waveform inversion. The rupture volume model was counted by the irregular grid statistics with the events’ density. It shows that the rock slide is of a small scale and composed of a single block. Moreover, the relationship among microseismicity, displacement and rainfall were discussed in the paper. The deformation rate was dramatically changed in the period of intensive events. There is a good consistency especially in the rainfall period. Although there is a time delay, continuous rainfall is more likely to cause the increase of microseismic events. The results show that the Dulong slope is a shallow rock slide in the state of creep deformation, and the rupture mechanism of the rock mass is left-lateral normal fault with shear failure. The research provides more key information for the early warning and prevention of rock slides and helps to reduce the risk of geohazards. 展开更多
关键词 Stability evaluation Microseismic monitoring Rock slide RAINFALL DISPLACEMENT
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Monitoring and Evaluation of Present Situation of Environmental Quality in the Sea Area near the Aojiang Estuary in Wenzou 被引量:1
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作者 Ye Maosen Yang Dan +4 位作者 Zhang Rongbao Xu Hengtao Zhang Haisheng Yao Dongping Ye Xinrong 《Meteorological and Environmental Research》 CAS 2017年第3期57-61,66,共6页
Based on the monitoring results of environmental quality in the sea area near the Aojiang estuary in Wenzou during 2010-2012,the present situation of environmental quality in the sea area was analyzed and evaluated. T... Based on the monitoring results of environmental quality in the sea area near the Aojiang estuary in Wenzou during 2010-2012,the present situation of environmental quality in the sea area was analyzed and evaluated. The results show that p H,DO,CODMn,petroleum,and heavy metals( Cu,Pb,Zn,Cd,Hg,As and Cr) in the sea area near the Aojiang estuary did not exceed the second-class standard of Seawater Quality Standard( GB 3097-1997),but both inorganic nitrogen and reactive phosphate in the sea area exceeded the second-class standard seriously,and the water quality of the sea area was in an eutrophic state; domestic sewage and fertilizer loss were the main sources of nitrogen and phosphorus. The standard index of most evaluation factors of sediment quality except for Zn was smaller than 1,meeting the demands of sediment quality for environmental protection. 展开更多
关键词 Sea area NEAR the Aojiang ESTUARY in Wenzou PRESENT SITUATION of environmental QUALITY monitoring evaluation Water QUALITY Sediment QUALITY
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Using Grey Target Theory for Power Quality Evaluation Based on Power Quality Monitoring Data 被引量:1
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作者 Qiang Yu Xiankai Chen +2 位作者 Xiaoyue Li Chaoqun Zhou Zhichao Li 《Energy Engineering》 EI 2022年第1期359-369,共11页
Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is propose... Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is proposed for power quality evaluation.The grey target is composed of power quality evaluation standard and power quality monitoring data to be evaluated.Combining with the characteristics of each power quality evaluation index,the target center of the whole grey target system is found.Then,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information space.Finally,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is obtained.Compared with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality. 展开更多
关键词 Smart grid power quality evaluation grey target theory monitoring data
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Establishment and evaluation of a theater influenza monitoring platform
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作者 Jian Wang Hui-Suo Yang +6 位作者 Bing Deng Meng-Jing Shi Xiang-Da Li Qing-Gong Nian Wen-Jing Song Feng Bing Qing-Feng Li 《Military Medical Research》 SCIE CAS 2018年第2期111-116,共6页
Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are ... Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control.Methods:As a theater centers for disease prevention and control,we established an influenza monitoring platform(IMP)in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection.In this study,we introduced the constitution,influenza virus detection,and quality control for an IMP.The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems.The experiences and problems associated with the platform also were summarized.Results:A theater IMP was established based on 3 levels of medical units,including monitoring sites,testing laboratories and a checking laboratory.A series of measures were taken to guarantee the quality of monitoring,such as technical training,a unified process,sufficient supervision and timely communication.The platform has run smoothly for 3 monitoring years to date.In the 2014–2015 and 2016–2017 monitoring years,sample amount coincided with that obtained from the National Influenza Surveillance program.In the 2015–2016 monitoring year,due to the strict prevention and control measures,an influenza epidemic peak was avoided in monitoring units,and the monitoring data did not coincide with that of the National Influenza Surveillance program.Several problems,including insufficient attention,unreasonable administrative intervention or subordination relationships,and the necessity of detection in monitoring sites were still observed.Conclusion:A theater IMP was established rationally and played a deserved role in the prevention and control of influenza.However,several problems remain to be solved. 展开更多
关键词 INFLUENZA monitoring MILITARY ESTABLISHMENT evaluation
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Geometric Conversion Approach for the Numerical Evaluation of Hypersin gular and Nearly Hypersingular Boundary Integrals over Curved Surface Boundary Elements
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作者 马杭 《Journal of Shanghai University(English Edition)》 CAS 2002年第2期101-110,共10页
With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation o... With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation of the hypersingular surface boundary integrals encountered in a variety of applications with boundary element method. Based on the conversion, the hypersingularity in the boundary integrals could be lowered by one order, resulting in the simplification of the computer code. Moreover, an integral transformation was introduced to damp out the nearly singular behavior of the kernels by the distance function defined in the local polar coordinate system for the nearly hypersingular case. The approach is simple to use, which can be inserted readily to computer code, thus getting rid of the dull routine deduction of formulae before the numerical implementations, as the expressions of these kernels are in general complicated. The numerical examples were given in three dimensional elasticity, verifying the effectiveness of the proposed approach, which makes it possible to observe numerically the behavior of the boundary integral values with hypersingular kernels across the boundary. 展开更多
关键词 boundary element method numerical evaluation hypersingular boundary integral nearly hypersingular boundary integral geometric conversion.
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Monitoring and Evaluation on Indoor Radon Concentration in a District of Xi'an
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作者 Huiping Guo Wenhui Lv +2 位作者 Ning Lv Lei Zhang Zhihao Wei 《Meteorological and Environmental Research》 CAS 2013年第10期25-27,31,共4页
[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi'an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents... [Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi'an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents, the investigation about the level of indoor radon in one district of Xi'an was developed. Based on the proper monitoring scheme, some typical living rooms were sampled. Through the measurement result, the effects of different factors on radon concentration were obtained. Finally, the radon concentration was transferred into the effective dose per year of local residents. [ Result] Indoor radon concentration in the district was during 49.680 -128.856 Bq/m3, and average concentration in each building was within 100 Bq/m3, which belonged to normal range. When sunny day became rainy day, radon concentration firstly had a rise trend. If continuous rainy weather appeared, indoor radon concentration gradually declined. When other conditions were same, indoor radon concentration under window closing was significantly higher than that under window opening. Indoor radon concentration had a decline trend from 13:00 to 20:00 and a rise trend from 01:00 to 06:00. Condusion The district belonged to radon safety house. To protect residents' health to the maximum extent, according to transfer change rule of the radon, window should be opened to ventilate in the morning when radon concentration was higher. 展开更多
关键词 Radon concentration monitoring and evaluation Variation regulation Effective dose China
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Vertical Displacement Monitoring and Safety Evaluation of Oil Pipelines in Permafrost Region
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作者 Liangliang Li Hongyu Ma Hongyuan Jing 《Journal of Geoscience and Environment Protection》 2018年第5期247-256,共10页
This paper presents the development of a liquid pressure based automatic monitoring device of the vertical displacement of oil pipeline that has good applicability to the extreme cold conditions of the permafrost regi... This paper presents the development of a liquid pressure based automatic monitoring device of the vertical displacement of oil pipeline that has good applicability to the extreme cold conditions of the permafrost region and is capable of automatic collection and transmission of monitoring data. The effectiveness of the device has been verified using total station measurement method and the results show that the device can intuitively indicate the vertical displacement of the pipe under the harmful influence of frost heaving and thaw settlement. According to the monitoring data, safety evaluation of the pipe during the monitoring period is carried out using stress-based design criteria and strain-based design criteria respectively. The analytic results with stress-based design criteria show that the pipe may be in a dangerous state while the results with strain-based design criteria show that the pipe is in a safe state. The design method with strain-based criteria is complementary to the design method with stress-based criteria. Separate use of either method is not recommended. 展开更多
关键词 FROZEN SOIL Pipelines monitoring SAFETY evaluation
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Comparison between Two Bioassays in Monitoring and Evaluation of Water Quality
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作者 XU Ya-ping LIU Feng-zhi +1 位作者 LIU Yan SHAO Xiao-long 《Meteorological and Environmental Research》 2012年第3期49-52,共4页
[ Objective] The aim was to compare the application of two bioassays to monitoring and evaluation of water quality. [ Method ] By using two bioassays (micronucleus detecting technology based on Vicia faba root tip ce... [ Objective] The aim was to compare the application of two bioassays to monitoring and evaluation of water quality. [ Method ] By using two bioassays (micronucleus detecting technology based on Vicia faba root tip cells and the bioassay by luminous bacteria), we monitored and evaluated seven kinds of single solutions respectively added different pollutants ( Hg, Cd, As, Cr6 + , Pb, I_A8 and CODc,) and a mixed solution added those seven pollutants. Afterwards, we compared their results under the same pollutant and concentration, so as to study the two bioassays' sensitivity and sensitive concentration to the seven pollutants. [ Result] Under the same pollutant and concentration, micronucleus detecting tech- nology based on Vicia faba root tip cells had responses to Hg, Cd, As and Cr6+ , but there was no response to Pb, LAS and CODer. However, the bioassay by luminous bacteria had responses to most pollutants except Cr6+. Comparing the sensitive degree and concentration to each pollutant, they can complement each other. For these seven pollutants, the bioassay by luminous bacteria was better than micronucleus detecting technology based on Vicia faba root tip cells. Meanwhile, from the testing result of the mixed solution, the combined toxicity of several pollutants in lower con- cantrations was serious. At the same time, contrasted to normal chemical methods, bioassays were fast and effective. [ Conclusion] The research could provide theoretical references for the correlation study of bioassays. 展开更多
关键词 BIOASSAY Water quality monitoring evaluation China
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Evaluation on abundance or deficiency of avai-lable trace elements in soil of middle area in China and the effect of applying trace element fertilizer
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作者 Li Jiyun Liu Xiudi +2 位作者 Fan Lihong Tong Yiping Yang Junhui(Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第3期361-372,共12页
The authors selected the west part of Xinxiang City,Henan Province in the north China plain as a typical region and carried out assessments of the abundanca or deficiency of the trace ele- ments(B,Mn,Mo,Zn,Cu,Fe)in s... The authors selected the west part of Xinxiang City,Henan Province in the north China plain as a typical region and carried out assessments of the abundanca or deficiency of the trace ele- ments(B,Mn,Mo,Zn,Cu,Fe)in soil.It can be seen from results that more than 80% of the farmland is deficiency of zinc(<1.0ppm),40% of molybdenum(0.15ppm),38% of boron(0.5ppm),29% of manganese(100ppm)and 13% of iron(7.0ppm)and that the content of available trace ele- ments in soil are related to the topography closely.Next the proper application of trace elements on grain crops is presented. 展开更多
关键词 evaluation available trace element soil type topography.
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Monitoring and Evaluation of Benefits of Project of Returning Farmland to Forests in Henan Province
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作者 Lu WANG Weiwei ZHANG +1 位作者 Qianzeng XU Xianwen ZHU 《Asian Agricultural Research》 2022年第11期17-20,共4页
The project of returning farmland to forest has been implemented and consolidated in Henan Province for 20 years.At present,it is in a critical transition period when the previous round of project of returning farmlan... The project of returning farmland to forest has been implemented and consolidated in Henan Province for 20 years.At present,it is in a critical transition period when the previous round of project of returning farmland to forests has completed and a new round of project of returning farmland to forests has started.Henan Province took counties(cities)with different representations as sample counties for monitoring the benefits of project of returning farmland to forests(key monitoring areas in Henan Province),and monitored social and ecological benefits every year,and has obtained real and scientific monitoring data. 展开更多
关键词 Returning farmland to forests Project benefits monitoring and evaluation
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Expert Anti-Evaluation Model Based on Matter-Element Analysis in Fund Project Peer-Review System
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作者 Haifeng Li Yanzhong Dang 《Intelligent Information Management》 2010年第3期227-231,共5页
The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and al... The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational. 展开更多
关键词 Anti-evaluation Model MATTER-ELEMENT Analysis Index SYSTEM Comprehensive evaluation PEER Review
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Evaluation of Petroleum System in Xihu Depression, East China Sea Shelf Basin 被引量:2
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作者 Ye Jiaren L■ Delin Faculty of Earth Resources , China University of Geosciences, Wuhan 430074 Gu Huirong Planning & Designing Institute, Shanghai Offshore Petroleum Bureau, Shanghai 200120 《Journal of China University of Geosciences》 SCIE CSCD 2001年第4期343-350,共8页
According to the theory of petroleum system and the characteristics of petroleum geology, the Xihu depression in the East China Sea shelf basin is divided into four petroleum systems: the Pinghu Formation as source ro... According to the theory of petroleum system and the characteristics of petroleum geology, the Xihu depression in the East China Sea shelf basin is divided into four petroleum systems: the Pinghu Formation as source rock and the Huagang Formation as reservoir rock, the Huagang Formation as source rock and reservoir rock, the Paleocene as source rock and the burial-hill as reservoir rock, and the Miocene as source rock and reservoir rock. The system with the Pinghu Formation as source rock and the Huagang Formation as reservoir rock is the most important one in the depression, which has high hydrocarbon generation and accumulation efficiency and is the most important object to hydrocarbon exploration at present. 展开更多
关键词 Xihu depression petroleum system geological element pool-forming process evaluation.
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Method for evaluation of the cleanliness grade of coal resources in the Huainan Coalfield,Anhui,China:a case study 被引量:1
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作者 Guangqing Hu Guijian Liu +2 位作者 Dun Wu Wenyong Zhang Biao Fu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第4期534-546,共13页
Based on analysis of a large data set and supplementary sampling and analysis for hazardous trace elements in coal samples from the Huainan Coalfield,a generalized contrast-weighted scale index method was used to esta... Based on analysis of a large data set and supplementary sampling and analysis for hazardous trace elements in coal samples from the Huainan Coalfield,a generalized contrast-weighted scale index method was used to establish a model to evaluate the grade of coal cleanliness and its regional distribution in the main coal seam(No.13-1)The results showed that:(1)The contents of Cr,Mn and Ni in the coal seam are relatively high and the average values are greater than 20μg/g.The contents of Se and Hg are at a high level while most other trace elements are at normal levels.(2)The cleanliness grade of the coal seam is mainly grade III-IV,which corresponds to a relatively good-medium coal cleanliness grade.However,some parts of the seam are at grade V(relatively poor coal cleanliness).(3)Coal of relatively good cleanliness grade(grade III)is distributed mainly in the regions corresponding to the Zhuji-Dingji-Gubei coal mines and in the eastern periphery of the Panji coal mine.Coal of medium cleanliness(grade IV)is distributed mainly in the regions of the Panji-Xiejiaji and Kouzidong coalmines.Relatively poor grade coal(grade V)is distributed in the southwest regions of the coalfield and the contents of Cr,As and Hg in coal collected from the relatively poor coal cleanliness regions often exceed the regulatory standards for the maximum concentration limits. 展开更多
关键词 Coal cleanliness Hazardous trace elements evaluation method Huainan coalfield
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Comparative evaluation of concrete sand-control fences used for railway protection in strong wind areas 被引量:2
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作者 Long Shi Dongyuan Wang +1 位作者 Kai Cui Chunxiao Xue 《Railway Engineering Science》 2021年第2期183-198,共16页
Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straig... Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straight or obliquely inserted concrete plates(SIP or OIP),significantly influence the efficiency of sand-control.This study performs a comparative evaluation of the SIP and OIP sand-control fences using wind tunnel testing and field monitoring data collected from the Lanzhou–Wulumuqi High-Speed Railway Project.The results show that the fence’s ability to reduce the wind speed and the sand-retaining efficiency gradually weakens with the increasing wind speed.Compared with the SIP fence,the OIP fence has a better wind speed reduction capability,stronger ability to capture fine particles below the top of the fence;it is more efficient for sand-retaining and induces stronger eddy intensity.Generally,the wind tunnel test and field monitoring results are consistent,whereas wind tunnel tests incline to overestimate wind speed reduction and sand-control efficiency.The study also finds that the aeolian sand accumulated around the fence can weaken the protection efficiency,and hence cleaning the aeolian sand accumulated around the fence should be done periodically to ensure the designed functions. 展开更多
关键词 Concrete-plate fences Plate-inserting methods Sand-control performance evaluation Wind-sand flow Wind tunnel test Field monitoring
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Aesthetic evaluation of yardang landforms landscape:the Dunhuang Yardang National Geo-park example
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作者 RuiJie Dong ZhiBao Dong 《Research in Cold and Arid Regions》 CSCD 2015年第3期265-271,共7页
Dunhuang Yardang National Geo-park, situated in the Gansu Province of northwestern China (40°25′36″N-40°33′10″N, 93°00′00″E-93°13′30″E), was chosen as a research locality of aesthetics ev... Dunhuang Yardang National Geo-park, situated in the Gansu Province of northwestern China (40°25′36″N-40°33′10″N, 93°00′00″E-93°13′30″E), was chosen as a research locality of aesthetics evaluation of yardang landforms landscape. The yardang landforms landscape is a composite structural system of patch-corridor-matrix, with four landscape unit elements as dense group, sparse group, single body and remnant. The study of the landscape aesthetics spatial pattern of Dunhuang Yardang National Geo-park shows that yardang dense group, sparse group and single body provide the greatest contribution to the aesthetic value of yardang landforms landscape. Yardang bodies are scarce, unique, irreplaceable, and priceless resources in yardang landforms areas. However, they are easily destroyed under the influence of the natural and artificial factors. Therefore, when the tourism potential of yardang landforms landscape is exploited, the protection should be fully improved. 展开更多
关键词 aesthetic evaluation yardang landforms landscape elements spatial structure Dunhuang
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