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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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Quantitative evaluation model of shale oil adsorption:A case study of the first member of Cretaceous Qingshankou Formation in northern Songliao Basin,NE China
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作者 LI Jinbu WANG Min +7 位作者 LU Shuangfang LIU Liang LI Ming ZHANG Yuchen WANG Xin ZHAO Xinbin ZHANG Jinyou ZHAO Ying 《Petroleum Exploration and Development》 SCIE 2023年第5期1137-1150,共14页
A quantitative evaluation model that integrates kerogen adsorption and clay pore adsorption of shale oil was proposed,and the evaluation charts of adsorption-swelling capacity of kerogen(Mk)and adsorbed oil capacity o... A quantitative evaluation model that integrates kerogen adsorption and clay pore adsorption of shale oil was proposed,and the evaluation charts of adsorption-swelling capacity of kerogen(Mk)and adsorbed oil capacity of clay minerals(Mc)were established,taking the 1st member of Cretaceous Qingshankou Formation in the northern Songliao Basin as an example.The model and charts were derived from swelling oil experiments performed on naturally evolved kerogens and adsorbed oil experiments on clays(separated from shale core samples).They were constructed on the basis of clarifying the control law of kerogen maturity evolution on its adsorption-swelling capacity,and considering the effect of both the clay pore surface area that occupied by adsorbed oil and formation temperature.The results are obtained in four aspects:(1)For the Qing 1 Member shale,with the increase of maturity,Mk decreases.Given Ro of 0.83%–1.65%,Mk is about 50–250 mg/g.(2)The clay in shale adsorbs asphaltene.Mc is 0.63 mg/m^(2),and about 15%of the clay pore surface is occupied by adsorbed oil.(3)In the low to medium maturity stages,the shale oil adsorption is controlled by organic matter.When Ro>1.3%,the shale oil adsorption capacity is contributed by clay pores.(4)The oil adsorption capacity evaluated on the surface at room temperature is 8%–22%(avg.15%)higher than that is held in the formations.The proposed evaluation model reveals the occurrence mechanisms of shale oils with different maturities,and provides a new insight for estimating the reserves of shale oil under formation temperature conditions. 展开更多
关键词 shale oil adsorbed oil occurrence state MOBILITY Cretaceous Qingshankou Formation evaluation model Songliao Basin
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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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Quantitative evaluation and spatial differentiation of eco-environmental livability in Zhejiang Province, China 被引量:2
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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 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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A Method for Vulnerability Database Quantitative Evaluation
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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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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 show... 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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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 mining subsidence.We designed a method for predicting LS factors of a mining subsidence basin,using analytical GIS spa... Based on a RUSLE model,we identified the key factors of the impact on soil erosion induced by coal mining subsidence.We designed a method for predicting LS factors of a mining subsidence basin,using analytical 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 subsidence basin without water logging would increase by 78% and 23% respectively compared with the original 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 modulus 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 especially at the edge of basins where water and soil conservation measures should be taken. 展开更多
关键词 土壤侵蚀定量评价 RUSLE 煤炭开采 沉陷盆地 土地 侵蚀模数 地面沉降 最大加速度
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Quantitative evaluation methods for waterflooded layers of conglomerate reservoir based on well logging data 被引量:21
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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 定量评价方法 砾岩油藏 水淹层 测井资料 原状地层电阻率 克拉玛依油田 复杂岩性 密闭取心井
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Quantitative Evaluation of Cyber-Attacks on a Hypothetical School Computer Network 被引量:1
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作者 Akinjide A. Akinola Adeyemi A. Adekoya +1 位作者 Ayoade O. Kuye Abiodun Ayodeji 《Journal of Information Security》 2019年第3期103-116,共14页
This paper presents the attack tree modeling technique of quantifying cyber-attacks on a hypothetical school network system. Attack trees are constructed by decomposing the path in the network system where attacks are... This paper presents the attack tree modeling technique of quantifying cyber-attacks on a hypothetical school network system. Attack trees are constructed by decomposing the path in the network system where attacks are plausible. Considered for the network system are two possible network attack paths. One network path represents an attack through the Internet, and the other represents an attack through the Wireless Access Points (WAPs) in the school network. The probabilities of success of the events, that is, 1) the attack payoff, and 2) the commitment of the attacker to infiltrate the network are estimated for the leaf nodes. These are used to calculate the Returns on Attacks (ROAs) at the Root Nodes. For Phase I, the “As Is” network, the ROA values for both attack paths, are higher than 7 (8.00 and 9.35 respectively), which are high values and unacceptable operationally. In Phase II, countermeasures are implemented, and the two attack trees reevaluated. The probabilities of success of the events, the attack payoff and the commitment of the attacker are then re-estimated. Also, the Returns on Attacks (ROAs) for the Root Nodes are re-assessed after executing the countermeasures. For one attack tree, the ROA value of the Root Node was reduced to 4.83 from 8.0, while, for the other attack tree, the ROA value of the Root Node changed to 3.30 from 9.35. ROA values of 4.83 and 3.30 are acceptable as they fall within the medium value range. The efficacy of this method whereby, attack trees are deployed to mitigate computer network risks, as well as using it to assess the vulnerability of computer networks is quantitatively substantiated. 展开更多
关键词 Cyber-Attack quantitative VULNERABILITY Assessment ATTACK Trees RETURN on ATTACK COUNTERMEASURES
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3D Modeling Quantitative Evaluation for the Underground Space Resources in Beijing City
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作者 Yi Tian,Jianping Chen,Limei Wang School of Land Resources and Technology,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期283-284,共2页
Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models... Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models to establish a practicable underground space resources quantitative evaluation system.It sets up 展开更多
关键词 CITY UNDERGROUND SPACE RESOURCES quantitative evaluation 3D MODELING
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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 定量评价 间作 农作物 土壤 营养物质
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A quantitative evaluation for well pattern adaptability in ultra-low permeability oil reservoirs:A case study of Triassic Chang 6 and Chang 8 reservoirs in Ordos Basin 被引量:1
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作者 ZHAO Jiyong AN Xiaoping +4 位作者 WANG Jing FAN Jianming KANG Xingmei TAN Xiqun LI Wenqing 《Petroleum Exploration and Development》 2018年第3期499-506,共8页
Based on the previous studies and development practice in recent 10 years, a quantitative evaluation method for the adaptability of well patterns to ultra-low permeability reservoirs was established using cluster anal... Based on the previous studies and development practice in recent 10 years, a quantitative evaluation method for the adaptability of well patterns to ultra-low permeability reservoirs was established using cluster analysis and gray correlation method, and it includes 10 evaluation parameters in the four aspects of optimal evaluation parameters, determination of weights for evaluation parameters, development stage division, and determination of classification coefficients. This evaluation method was used to evaluate the well pattern adaptability of 13 main ultra-low permeability reservoirs in Triassic Chang 6 and Chang 8 of Ordos Basin. Three basic understandings were obtained: Firstly, the well pattern for ultra-low permeability type-I reservoirs has generally good adaptability, with proper well pattern forms and well pattern parameters. Secondly, square inverted nine-spot well pattern is suitable for reservoirs with no fractures; rhombic inverted nine-spot injection pattern is suitable for reservoirs with some fractures; and rectangular well pattern is suitable for reservoirs with rich fractures. Thirdly, for the ultra-low permeability type-Ⅱ and type-Ⅲ reservoirs, with the principles of well pattern form determination, the row spacing needs to be optimized further to improve the level of development of such reservoirs. 展开更多
关键词 ultra-low permeability oil reservoir well pattern adaptability comprehensive evaluation parameter ORDOS Basin TRIASSIC CHANG 6 FORMATION CHANG 8 FORMATION
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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 concept of sustainable development emerged in the late 1980s, more and more countries and re-gions have been utilizing sustainable development as their developing strategy. But decades have passed without an... Since the concept of sustainable development emerged in the late 1980s, more and more countries and re-gions have been utilizing sustainable development as their developing strategy. But decades have passed without any effective methods available to quantitatively assess sustainable development. Since the ecological footprint evalua-tion method initiated in 1992, it has become popular in quantitative assessment of sustainable development because of its convenience, easy-understanding, and reliability. 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 ecological footprint and biocapacity in 2005 were 2.507gha/cap and 0.276gha/cap respectively. The ecological defi cit was 2.230gha/cap. And from 1980 to 2005, Tianjin's ecologi-cal defi cit per 104 yuan GDP decreased; while per capita ecological def icit has been tending to increase rapidly in recent years. All these results demonstrate that Tianjin is in a state of unsustainable development. 展开更多
关键词 天津 生态承受力 生态经济 经济发展
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Objective and quantitative evaluation of environmental quality of the land for agriculture purpose
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作者 Ning Datong, Wang Sufen and Sun RuomeiInstitute of Environmental Sciences,Beijing Normal University,Beijing 100875,ChinaInstitute of Rural Development,Chinese Academy of Social Science,Beijing 100020,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1991年第1期1-10,共10页
An objective and quantitative evaluation method on land environmental quality for agricultural purpose in a county range is studied in this paper. The method takes into account the quantity of heat, precipitation, met... An objective and quantitative evaluation method on land environmental quality for agricultural purpose in a county range is studied in this paper. The method takes into account the quantity of heat, precipitation, meteorological disaster and soil fertility, which have close relationship to the potential productivity of land and can be expressed conveniently and accurately by taking Kai County as an example. Besides comprehensive grading assessment, assessment with Hilbert Space distance coefficiency and comprehensive judgement by fuzzy sets theory, the assessment factors are expanded to 18 parameters, and fuzzy dominance matrix and fuzzy clustering methods are adopted for regional comprehensive identification of agriculture-use land. Among these methods, each benefits from association with the other. In this paper, an all-round and objective new way for understanding of land environmental quality is put forward. 展开更多
关键词 LAND RESOURCE ENVIRONMENTAL quality model evaluation identification.
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Quantitative evaluation of diffusion-weighted magnetic resonance imaging of focal hepatic lesions 被引量:21
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作者 Xi-Jie Sun Xian-Yue Quan +1 位作者 Fan-Heng Huang Yi-Kai Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第41期6535-6537,共3页
AIM: To explore the quantitative analysis of diffusionweighted magnetic resonance imaging (DWMRI) in differential diagnosis of focal hepatic lesions.METHODS: DWMRI was performed in 149 hepatic lesions, including hepat... AIM: To explore the quantitative analysis of diffusionweighted magnetic resonance imaging (DWMRI) in differential diagnosis of focal hepatic lesions.METHODS: DWMRI was performed in 149 hepatic lesions, including hepatocellular carcinoma (34 cases),hepatic metastases (37 cases), cavernous hemangioma (42 cases), hepatic cyst (36 cases). Apparent diffusion coefficient (ADC) values were evaluated using four different b values in different sequences. The ratio of ADC values of lesion/liver in hepatocellular carcinoma and hepatic metastases was also calculated.RESULTS: The mean ADC values of hepatic lesions were as follows: hepatocellular carcinoma (0.95 ± 0.11) × 10-3 mm2/s, hepatic metastasis (1.13 ± 0.21)× 10-3 mm2/s, cavernous hemangioma (1.86±0.36)×10-3 mm2/s,hepatic cyst(3.14±0.31)×10-3 mm2/s. The ratio of ADC values in lesion/liver in hepatocellular carcinoma was 0.91 ±0.11, being significantly different from that in hepatic metastasis (1.21 ± 0.18, P< 0.05).CONCLUSION: ADC values and quantitative analysis of focal hepatic lesions are of significant values in differential diagnosis of focal hepatic lesions. 展开更多
关键词 肝损伤 磁共振成像 定量检查 加权成像
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Survey on quantitative evaluations of moving target defense 被引量:1
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作者 Huanruo LI Yunfei GUO +2 位作者 Shumin HUO Guozhen CHENG Wenyan LIU 《网络与信息安全学报》 2018年第9期66-76,共11页
Quantitative evaluations are of great importance in network security decision-making.In recent years,moving target defense(MTD)has appeared to be a promising defense approach that blocks asymmetrical advantage of atta... Quantitative evaluations are of great importance in network security decision-making.In recent years,moving target defense(MTD)has appeared to be a promising defense approach that blocks asymmetrical advantage of attackers and favors the defender-notwithstanding,it has a limited deployment due to its uncertain efficiency and effectiveness in defense.In that case,quantitative metrics and evaluations of MTD are essential to prove its capability and impulse its further research.This article presents a comprehensive survey on state-of-the-art quantitative evaluations.First,taxonomy of MTD techniques is stated according to the software stack model.Then,a concrete review and comparison on existing quantitative evaluations of MTD is presented.Finally,notice-worthy open issues regarding this topic are proposed along with the conclusions of previous studies. 展开更多
关键词 计算机网络 网络管理 应用程序 信息安全
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Standardized Semi-Quantitative Evaluation of [123I]FP-CIT SPECT in a Multicenter Study
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作者 Andrea Skanjeti Giancarlo Castellano +10 位作者 Baldassarre Elia Francesca Dazzara Michela Zotta Gabriela Mariam Delgado Yabar Matteo Manfredi Marco Iudicello Maurizio Zibetti Patrizia Ferrero Paola Filippi Riccardo Emanuele Pellerito Valerio Podio 《Advances in Molecular Imaging》 2013年第4期55-60,共6页
To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitat... To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitative software-assisted evaluations of DAT-SPECTs performed in three centers with different equipments;2) to assess the accuracy of semi-quantitative evaluations of DAT-SPECT and 3) to identify the threshold with the best accuracy, sensitivity and specificity in a patient population with suspected parkinsonian syndrome. Materials and Methods: Two hundred twenty patients (mean age at the time of SPECT acquisition, 67.4 ± 9.5 yy) acquired in three centers (Ospedale San Luigi Gonzaga;Ospedale San Giovanni Battista Molinette;Ospedale Mauriziano Umberto I) were included. All of them underwent DAT-SPECT from January 2006 to July 2010. All exams were analyzed with the freely available software BASGAN and semi-quantitative data were used to predict disease. In particular, analyses were based on the values from the most deteriorated putamen and caudate, normalized for age and corrected for equipment. ROC analysis was performed and area under the curve (AUC) was estimated. Results: Analysis showed high AUCs (0.898, 0.864, 0.900 and 0.891 for each center and for the multicenter setting, respectively) confirming the very good accuracies reached. The best cut-off were 0.72 and 0.82 for putamen and caudate respectively. These thresholds allowed sensitivities and specificities in each center and in the multicenter setting of 76% and 96%, 91% and 82%, 93% and 90%, 86% and 89% respectively. No significant differences were observed between sensibility and specificity in each center. Conclusion: A unique threshold useful for all centers with high and similar sensitivities and specificities is possible after correction for age and equipments. The high accuracy reached in this multicenter trial by the semi-quantitative analysis seems similar to accuracies from qualitative analysis in other multicenter studies. 展开更多
关键词 Movement DISORDER PARKINSON Disease [123I]FP-CIT-SPECT SEMI-quantitative evaluation MULTICENTER Study
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The Analysis of an HIV and AIDS Empowering Group Work Programme for Adolescents: A Quantitative Evaluation
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作者 K. Olivier H. Strydom 《World Journal of AIDS》 2013年第1期57-65,共9页
In this article an HIV and AIDS group work programme empowering adolescents to deal with the possible death of their parents/caregivers will be evaluated in a quantitative fashion. The data were obtained by means of t... In this article an HIV and AIDS group work programme empowering adolescents to deal with the possible death of their parents/caregivers will be evaluated in a quantitative fashion. The data were obtained by means of the Child Functioning Inventory High School (CFI-HIGH) developed by Perspective Training College and the Generalized Contentment Scale (GCS) of Hudson (Bloom et al., 1999: 220). The guidelines for selection and inclusion of respondents in the comparison and experimental groups will be discussed, followed by information on the measuring instruments. The article will conclude with conclusions and recommendations. 展开更多
关键词 evaluation HIV and AIDS Empowering GROUP WORK PROGRAMME Adolescents
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