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A Quantitative Method for Evaluating the Transporting Capacity of Oil-Source Faults in Shallow Formation of Oil-Rich Sags 被引量:4
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作者 JIANG Youlu ZHAO Kai +1 位作者 LIU Jingdong LU Xueying 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1678-1679,共2页
Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins (Jiang Youlu et al., 2015). Howev... Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins (Jiang Youlu et al., 2015). However, the fault transporting capacity cannot be evaluated quantitatively at present. Taking the Zhanhua Sag in the Bohai Bay Basin as an example, this work analyzed the factors influencing the transporting capacity of the oil-source faults and proposed a quantitative method for evaluating their transporting capacity. 展开更多
关键词 A quantitative Method for evaluating the Transporting Capacity of Oil-Source Faults in Shallow Formation of Oil-Rich Sags
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Determination of Consistency between Quantitative Evaluation and Non-quantitative Evaluation
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作者 史倩 刘国华 《Journal of Donghua University(English Edition)》 CAS 2023年第3期334-342,共9页
The combination of quantitative evaluation(QE)and non-quantitative evaluation(NQE)is an important evaluation tool in the fields of academic level evaluation(e.g.,EasyChair,Academic paper review form)and internet commo... The combination of quantitative evaluation(QE)and non-quantitative evaluation(NQE)is an important evaluation tool in the fields of academic level evaluation(e.g.,EasyChair,Academic paper review form)and internet commodity evaluation(e.g.,Amazon’s review,Feedback).But the inconsistency between QE and NQE greatly reduces the correctness and usability of the evaluation.Therefore,it is a necessary task to judge whether QE is consistent with NQE.In this paper,the predicate formula satisfiability problem is firstly reduced in polynomial time to the consistency problem of QE and NQE,and the uncertainty of the consistency problem is proved.Then the approximate solution to the problem is investigated by using a natural language processing method,which performs sentiment analysis on NQE and finally invokes a database query statement to determine whether QE is consistent with NQE.The results shed light on the feasibility of using the natural language processing method to solve undecidable problems. 展开更多
关键词 quantitative evaluation(QE) non-quantitative evaluation(NQE) satisfiability problem natural language processing sentiment analysis
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Analysis of System Value Evolution Trends of Energy Storage in Decarbonization Process
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作者 Mo Zhou Jingming Zhao +3 位作者 Zili Chen Qiushi Fang Hua Li Zhaoyuan Wu 《Energy Engineering》 EI 2024年第10期3037-3053,共17页
With the continuous expansion of the scale of renewable energy installation,the demand for energy storage has increased significantly.However,there are significant differences in the value of energy storage in differe... With the continuous expansion of the scale of renewable energy installation,the demand for energy storage has increased significantly.However,there are significant differences in the value of energy storage in different scenarios,and the phenomenon of diminishing marginal benefits of energy storage is becoming more apparent.Therefore,themulti-dimensional value evolution trend of energy storage has become a key issue.This study selects indicators from three dimensions of energy storage:low-carbon emission reduction,smoothing wind and solar power fluctuations,and saving generation costs,quantifying the economic,environmental,and technical values of energy storage.This forms a quantitative evaluation system for energy storage value.By comparing the calculated system values under different energy storage capacities,the marginal value evolution trend of energy storage is obtained.Meanwhile,considering factors such as the utilization rate of renewable energy,the change in energy storage value under different scenarios is analyzed.The results show that the value of long-duration energy storage is significantly affected by the energy storage capacity.Specifically,when the charge-discharge efficiency of longduration energy storage reaches 0.6 or above,the system value increases significantly.Additionally,appropriately reducing the cost of energy storage capacity also helps to improve its system value. 展开更多
关键词 quantitative evaluation of value marginal benefit joint planning value evolution trend
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The Application of Digital Optical 3D Image Analyzer Evaskin in The Evaluation of Wrinkles
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作者 Wang Xingkai Liu Hui +3 位作者 Liu Fei Chen Bowen Wu Tao Yang Suzhen 《China Detergent & Cosmetics》 CAS 2024年第3期62-66,共5页
To verify the effectiveness of digital optical 3D image analyzer EvaSKIN in the objective and quantitative evaluation of wrinkles.A total of 115 subjects were recruited,the facial images of the subjects were collected... To verify the effectiveness of digital optical 3D image analyzer EvaSKIN in the objective and quantitative evaluation of wrinkles.A total of 115 subjects were recruited,the facial images of the subjects were collected by digital optical 3D image analyzer and manual camera,the changes of crow’s feet with age were analyzed.Pictures obtained by manual photography can be directly used for observation and preliminary grading of wrinkles.However,the requirements for evaluators are high,and the results are prone to errors,which will affect the accuracy of the evaluation.Therefore,skilled raters are needed.Compared with the manual photography method,the digital optical 3D image analyzer EvaSKIN can realize three-dimensional extraction of wrinkles,and obtain the change trend of crow’s feet with age.20~30 years old,wrinkles begin to appear slowly;wrinkles will increase rapidly at the age of 30~50;The length of 50~60 year old wrinkles is basically fixed,the wrinkles develop longitudewise,gradually widen and deepen,and the area,depth and volume increase is obvious,and the skin aging condition is intensified.the digital optical 3D image analyzer EvaSKIN realizes the 3D extraction of wrinkles,quantifies the circumference,area,average depth,maximum depth and volume of wrinkles,realizes the objective and quantitative evaluation of wrinkle state,is more accurate in the measurement of wrinkles,and provides a new instrument and method for the evaluation of wrinkles.it is a perfect and supplement to the traditional evaluation methods,and to a certain extent,it helps the research and development and evaluation institutions of cosmetics to obtain more abundant and three-dimensional data support. 展开更多
关键词 digital optical 3D image analyzer EvaSKIN skin wrinkles age quantitative evaluation
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Quantitative evaluation methods for waterflooded layers of conglomerate reservoir based on well logging data 被引量:22
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作者 Tan Fengqi Li Hongqi +2 位作者 Xu Changfu Li Qingyuan Peng Shouchang 《Petroleum Science》 SCIE CAS CSCD 2010年第4期485-493,共9页
The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Qu... The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs. 展开更多
关键词 Water-flooded layer quantitative evaluation conglomerate reservoir lithology identification decision tree characteristic parameters
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Evaluation of the weakening behavior of gas on the coal strength and its quantitative influence on the coal deformation 被引量:6
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作者 Haijun Guo Kai Wang +5 位作者 Yuchen Wu Hanlu Tang Jianguo Wu Lianhe Guan Chenyang Chang Chao Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第3期451-462,共12页
The coal strength and deformation properties are key factors affecting safe coal mining and highefficiency coalbed methane(CBM)development.In this paper,reconstituted coal samples are chosen to investigate the weakeni... The coal strength and deformation properties are key factors affecting safe coal mining and highefficiency coalbed methane(CBM)development.In this paper,reconstituted coal samples are chosen to investigate the weakening behavior of gas on coal strength,meanwhile,its effects on coal deformation are quantitatively evaluated.The results indicate that the weakening degree of gas on coal strength is closely related to the confining stress and gas pressure.Compared with non-gas-saturated coals,the maximum weakening ratios of adsorbed gas to coal strength are 10.58%,18.12%,8.55%and 14.65%under the conditions of confining stress CS=3 MPa and gas pressure GP=1 MPa,CS=3 MPa and GP=2 MPa,CS=4 MPa and GP=1 MPa,and CS=4 MPa and GP=2 MPa,respectively.Furthermore,the maximum weakening ratios of free gas to coal strength are 18.27%,36.54%,14.79%and 29.58%,respectively,under above four conditions.The maximum coal bulk strain decreases as particle sizes of coal powders increase,and it has a maximum value of 0.0227 and a minimum value of 0.0191 in particle size ranges of 0.01–0.041 and 0.5–1 mm.Under the same conditions,the coal bulk strain increases with increasing gas pressure,revealing that coal deformation properties can be enhanced by gas. 展开更多
关键词 Gas-saturated coal Coal strength Weakening effect Coal deformation quantitative evaluation Mechanical loading
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Quantitative evaluation of soil erosion of land subsided by coal mining using RUSLE 被引量:13
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作者 Meng Lei Feng Qiyan +1 位作者 Wu Kan Meng Qingjun 《International Journal of Mining Science and Technology》 2012年第1期7-11,共5页
Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical ... Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical GIS spatial technology. Using the Huainan mining area as an example, we calculated the modulus of erosion, its volume and classified the grade of soil erosion for both the original area and the subsidence basin. The results show that the maximum modulus of erosion and the volume of erosion of the subsi- dence basin without water logging would increase by 78% and 23% respectively compared with the ori- ginal situation. The edge of the subsidence basin, where the land subsidence was uneven, is subject to the greatest acceleration in soil erosion. In the situation of water logging after subsidence, the maximum modulus of erosion would decrease if the accumulated slope length were reduced. This maximum mod- ulus around the water logged area within the subsidence basin is equal to that without water logging, while the total volume of erosion decreases. Therefore, mining subsidence aggravates soil erosion espe- cially at the edge of basins where water and soil conservation measures should be taken. 展开更多
关键词 RUSLE Coal mining subsidence Soil erosion quantitative evaluation
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Quantitative evaluation and spatial differentiation of eco-environmental livability in Zhejiang Province, China 被引量:4
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作者 WANG Yi ZHU Ying-ming +1 位作者 YU Mao-jun XU Jing 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1491-1508,共18页
The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of ... The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of major significance in the guidance of the coordinated development between social economies,natural resources,and environments.In this study,the topography,climate,hydrology,land cover,air quality,and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability.Then,the observed spatial patterns and regional differences in the eco-environmental livability,as well as their relationships with the distributions of population and economic activities in Zhejiang Province,were investigated.The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast,as well as from the mountains to the hills,valleys,and plains areas.During the compartmentalization of the eco-environmental livability,it was observed that the lowest livable area covered the largest population,accounting for approximately 29.64%of the total population in the study area.The higher livable areas covered the widest land areas,accounting for approximately 26.15%of the total area.Moreover,it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province.Furthermore,the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R^2 of the curve-fittings reaching 0.835 and 0.656,respectively.However,it was determined that the coefficient of the exponential function was negative,which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities.It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation.This study introduced two new factors(air quality and natural hazards)into the evaluation framework of eco-environmental livability.As a result,a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally,the correlation between ecoenvironment livability and human activities was discussed in-depth,which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China,and possibly even those of other vast developing countries. 展开更多
关键词 ECO-ENVIRONMENT LIVABILITY quantitative evaluations Spatial differentiation Zhejiang Province
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Quantitative evaluation of multi-process collaborative operation in steelmaking–continuous casting sections 被引量:3
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作者 Jian-ping Yang Qing Liu +1 位作者 Wei-da Guo Jun-guo Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1353-1366,共14页
The quantitative evaluation of multi-process collaborative operation is of great significance for the improvement of production planning and scheduling in steelmaking–continuous casting sections(SCCSs). However, this... The quantitative evaluation of multi-process collaborative operation is of great significance for the improvement of production planning and scheduling in steelmaking–continuous casting sections(SCCSs). However, this evaluation is difficult since it relies on an in-depth understanding of the operating mechanism of SCCSs, and few existing methods can be used to conduct the evaluation, due to the lack of full-scale consideration of the multiple factors related to the production operation. In this study, three quantitative models were developed, and the multiprocess collaborative operation level was evaluated through the laminar-flow operation degree, the process matching degree, and the scheduling strategy availability degree. Based on the evaluation models for the laminar-flow operation and process matching levels, this study investigated the production status of two steelmaking plants, plants A and B, based on actual production data. The average laminar-flow operation(process matching) degrees of SCCSs were obtained as 0.638(0.610) and 1.000(0.759) for plants A and B, respectively, for the period of April to July 2019. Then, a scheduling strategy based on the optimization of the furnace-caster coordinating mode was suggested for plant A. Simulation experiments showed higher availability than the greedy-based and manual strategies. After the proposed scheduling strategy was applied,the average process matching degree of the SCCS of plant A increased by 4.6% for the period of September to November 2019. The multi-process collaborative operation level was improved with fewer adjustments and interruptions in casting. 展开更多
关键词 steelmaking–continuous casting multi-process collaborative operation quantitative evaluation model laminar-flow operation process matching scheduling strategy
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A quantitative model for danger degree evaluation of staged operation of earth dam reservoir in flood season and its application 被引量:3
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作者 Chong-xun Mo Gui-yan Mo +3 位作者 Qing Yang Yu-li Ruan Qing-ling Jiang Ju-liang Jin 《Water Science and Engineering》 EI CAS CSCD 2018年第1期81-87,共7页
Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for ... Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season. 展开更多
关键词 Reservoir staged operation in flood season Earth dam Danger degree quantitative evaluation Overtopping risk rate
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Synthetically quantitative evaluation function of characteristic parameters on CO_2 arc welding process 被引量:4
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作者 俞建荣 蒋力培 +2 位作者 史耀武 孙振国 王军波 《China Welding》 EI CAS 2001年第1期19-26,共8页
The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis sh... The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis shows that the sensitivity of each characteristic parameter with regard to the variation of the short circuiting transfer process is different. The sensitivity of 4 kinds among these characteristic parameters is more intense than that of the short circuiting transfer frequency. In order to take account of the synthetic influence of these characteristic parameters, by means of the characteristic parameters synthetic value, a quantitative evaluation function is built up to describe and evaluate the short circuiting transfer process of CO 2 arc welding in real time. The testing shows that the evaluation function can give a suitable synthetic valuation for the short circuiting transfer process with a variety of welding variables. 展开更多
关键词 CO 2 arc welding process characteristic parameters quantitative evaluation function
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The Quantitative Evaluation of Output Efficiency in Different Cropping Patterns 被引量:1
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作者 LIU Yu-hua ZHANG Li-feng 《Agricultural Sciences in China》 CAS CSCD 2006年第2期98-102,共5页
Quantitative indexes such as land equivalent ratio, yield equivalent and value of output equivalent were used to evaluate output efficiencies of different cropping patterns, i.e., sequential cropping, intercrops and c... Quantitative indexes such as land equivalent ratio, yield equivalent and value of output equivalent were used to evaluate output efficiencies of different cropping patterns, i.e., sequential cropping, intercrops and crop rotation. Compared to single cropping, land use efficiencies under sequential cropping, intercrops and crop rotation were raised by 62, 38 and 21%, respectively. The unit area yield under sequential cropping, intercrops and crop rotation were raised by 63, 29 and 16%, respectively. The unit area value was also enhanced under sequential cropping and intercrops, 76 and 35% higher than that under single cropping. The paper provides a useful tool for comparing farm output efficiency and build up a theoretical basis for further research on output efficiency of various cropping patterns in the future. 展开更多
关键词 sequential cropping INTERCROPS ROTATION cropping patterns quantitative evaluation
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A Method for Vulnerability Database Quantitative Evaluation 被引量:1
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作者 Tiantian Tan Baosheng Wang +2 位作者 Yong Tang Xu Zhou Jingwen Han 《Computers, Materials & Continua》 SCIE EI 2019年第9期1129-1144,共16页
During system development,implementation and operation,vulnerability database technique is necessary to system security;there are many vulnerability databases but a lack of quality standardization and general evaluati... During system development,implementation and operation,vulnerability database technique is necessary to system security;there are many vulnerability databases but a lack of quality standardization and general evaluation method are needed.this paper summarized current international popular vulnerability databases,systematically introduced the present situation of current vulnerability databases,and found the problems of vulnerability database technology,extracted common metrics by analyzing vulnerability data of current popular vulnerability databases,introduced 4 measure indexes:the number scale of vulnerabilities,the independence level,the standardization degree and the integrity of vulnerability description,proposed a method for vulnerability database quantitative evaluation using SCAP protocol and corresponding standard,analyzed a large number of vulnerabilities in current popular vulnerability database,quantitative evaluated vulnerability database by the law of normal distribution,the experimental results show this method has strong versatility and science,and it is beneficial to improve the quality and standardization construction for vulnerability database development. 展开更多
关键词 Vulnerability management vulnerability database quantitative evaluation
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Quantitative evaluation of sustainable development based on ecological footprint method: a case study of Tianjin 被引量:2
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作者 Guo Wenyong Huang Qiaohua 《Ecological Economy》 2008年第2期172-179,共8页
Since the coneept of sustainable devetopment emerged in the late 1980s, more and more countries and regions have been utilizing sustainable development as their developing stratety. But decades have passed without any... Since the coneept of sustainable devetopment emerged in the late 1980s, more and more countries and regions have been utilizing sustainable development as their developing stratety. But decades have passed without any effective methods available to quantitatively assess sustainable development. Since the ecological footprint evaluation method initiated in 1992, it has become popular in quantitative assessment of sustainable development because of its convenience, easy-understanding, and rehability. As one of the biggest coastal cities in north China and the economic center of the Bohai Coastal Region, Tianjin's gross domestic product (GDP) was 369. 762 billion yuan in 2005, accounting for 2.0°of the whole nation's GDP. The paper analyzes Tianjin's development with the ecological footprint method, and the results show that Tianjin's ecoiogical footprint and biocapacity in 2005 were 2.507gha/cap and 0.2 76gha/cap respectively. The ecological deficit was 2.230gha/cap.And from 1980 to 2005,Tianjin's ecological deficit per 10^4 yuan GDP decreased;while per capita ecological deficit has been tending to increase rapidly in recent years.All these result demonstrate that Tianjin is in a state of unsustainable development. 展开更多
关键词 Ecological footprint BIOCAPACITY Sustainable development quantitative evaluation TIANJIN
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Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata(Haw.)using high performance thin layer chromatography 被引量:1
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作者 Nishi Srivastava Sharad Srivastava +2 位作者 Shikhar Verma Ajay Kumar Singh Rawat Abdul Rahman Khan 《The Journal of Biomedical Research》 CAS 2014年第4期328-331,共4页
Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distribut... Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distributed in Central and East Asia with about 30 species reported worldwide. It grows at a range of altitudes from the Khasia hills at 400 feet to the temperate Himalayas from Kashmir to Bhutan at 7,000-10,000 feet. Its distribution over a wide range of altitudinal zones makes it a good candidate for studying variations in its metabolic profiles under different climatic conditions. Bergenin (C-glycoside of 4-O-methyl gallic acid) has been identified as a potent active secondary metabolite in Bergenia and other therapeutically active constituents including, among others, gallic acid (3,4,5 trihydroxybenzoic acid), (+) catechin, and gallicin (Fig. 1). 展开更多
关键词 HPTLC using high performance thin layer chromatography Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata Haw HIGH
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Quantitative Evaluation of Sea-ice Disaster in Bohai Sea Based on GOCI and Sentinel-1 被引量:1
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作者 Meijie LIU Jin WANG +5 位作者 Shilei ZHONG Hao YOU Qi LIANG Ting CHEN Wenbo LI Xiaohan YANG 《Journal of Geodesy and Geoinformation Science》 2021年第1期49-55,共7页
The Circum-Bohai-Sea Region is an important economic zone of China.The sea ice,which occurs at each winter,is the major marine hazard of the Bohai Sea.As a result,it is very important to evaluate the damage effects qu... The Circum-Bohai-Sea Region is an important economic zone of China.The sea ice,which occurs at each winter,is the major marine hazard of the Bohai Sea.As a result,it is very important to evaluate the damage effects quantitatively in this region,which is seldom studied and analyzed systematically using long-time-series data.In this paper,the sea-ice disaster in the Bohai Sea is evaluated quantitatively based on the Sentinel-1 and GOCI.For different hazard-bearing bodies of the marine transportation and the offshore constructions,different sea-ice-hazard indexes are defined,which can be applied to analyze the sea-ice disaster quantitatively in the Bohai Sea,including the annual and inter-annual variations in the period from 2011 to 2017.The analysis results can provide the reference of the sea-ice monitoring in the Bohai Sea. 展开更多
关键词 the Bohai Sea sea-ice disaster the quantitative evaluation Sentinel-1 GOCI
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Quantitative Evaluation of Ecological Cumulative Effects and Zoning Regulations for Prefectural Mining Units in China
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作者 MA Li KANG Lei +1 位作者 TIAN Huazheng XU Die 《Chinese Geographical Science》 SCIE CSCD 2022年第1期49-63,共15页
Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental problems.Strengthening the spatial re... Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental problems.Strengthening the spatial regulation considering the ecological and environmental protection on energy and mineral resource development areas is an important aspect of realizing China’s sustainable development.In this study,we mapped,categorized,and analyzed the ecological cumulative effects of the Chinese 134 prefectural mining units based on the pressure-state-response model,which is demonstrated as impact of mining activities on ecological environment,ecological environmental fragility,and ecological function.This investigation developed a stress zoning typology of the mining units based on scores of three dimensions of the ecological cumulative effects and classified 134 prefectural mining units into eight types of stress zones.A series of regulation and policy suggestions have been proposed to different types of zones from three aspects:space control,intensity control,and development mode control.The application of this evaluation and spatial zoning system will contribute to the refined spatial management of China’s mining areas. 展开更多
关键词 ecological cumulative effects quantitative evaluation pressure-state-response model ZONING
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Quantitative Evaluation on Wetland Ecosystem Service Function in Chao Lake
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作者 唐晓先 高芮 《Agricultural Science & Technology》 CAS 2016年第11期2489-2492,2504,共5页
[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [... [Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows: flood mitigation 〉water purification 〉water conservation 〉 tourism&leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands. 展开更多
关键词 Chao Lake Wetland ecosystem service function quantitative evaluation
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Quantitative Seismic Risk Evaluation on Blind Faults in Offshore Areas of Tianjin,China
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作者 Liu Hongyan Chen Yukun +1 位作者 Yan Chengguo Yang Fei 《Earthquake Research in China》 2013年第4期542-552,共11页
Based on faults surveying and research data in the Tianjin offshore areas,through studying tectonic structure,Quaternary activity,deep structure,stress and strain fields and seismicity in the Tianjin offshore areas,th... Based on faults surveying and research data in the Tianjin offshore areas,through studying tectonic structure,Quaternary activity,deep structure,stress and strain fields and seismicity in the Tianjin offshore areas,the activity and tectonic features of the faults are determined synthetically.Using seismo-geological data,and the historical and modern seismicity data,the frequency-magnitude relationship model normalized by 500a is established and based on the relationship between the upper limit of maximum magnitude M u and a t/b,the maximum magnitudes of the sea section of the Haihe river fault and the Haiyi fault are calculated.Then Poisson probability model is adopted and the quantitative parameters,such as the maximum magnitude,occurrence probability,recurrence cycle of the faults in the south Tianjin offshore areas in the coming 50~200a,are calculated. 展开更多
关键词 Seismic risk quantitative evaluation Fault sub-area Frequency-magnituderelationship Maximum magnitude Occurrence probability Recurrenceperiod
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Preliminary Study on Quantitative Research Methods of Discussion-based Teaching: CAD/CAM Course
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作者 FAN Yiqiang ZHANG Yiyi +2 位作者 HE Dongmei YU Yuan ZHANG Yajun 《International Journal of Plant Engineering and Management》 2018年第2期71-78,共8页
Computer-aided design and manufacturing, or CAD/CAM, in a narrow sense, is the use of a computer for component design and machining. As a specialized course for students, CAD/CAM course is a required course for underg... Computer-aided design and manufacturing, or CAD/CAM, in a narrow sense, is the use of a computer for component design and machining. As a specialized course for students, CAD/CAM course is a required course for undergraduates majoring in mechanical engineering and related engineering majors and also the core technical skills to be mastered during the undergraduate study. Based on the teaching practices of CAD/CAM course, this paper tries to introduce the discussion-based method in curriculum design and the implementation of the course, and enhance the interaction between teachers and students through using new information interaction tools such as WeChat group and course homepage to stimulate students' interest, and also expand the learning space and time. Thus, the problems students have will be solved in real time. In this study, for the first time, the statistical methods are used to record detailed the speaking students' interaction, and also carries out quantitative time, keywords and the frequency of teachers and analysis in order to explore the interactive patterns between teacher and students in discussion-based teaching, so as to improve communication and learning efficien between teacher and students. Meanwhile, this paper also discussed the advantages and the disadvantages cy of using discussion-based teaching in the hope that it can provide reference for the following discussion-based teaching of CAD/CAM course in mechanical or related engineering majors. 展开更多
关键词 discussion-based teaching quantitative evaluation teacher-student interaction
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