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Study on Correlation of Different Methods of Evaluating Degree of Skin Redness
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作者 Jian Yuanqing Ma Lin +3 位作者 Huang Bingting Li Jing Zhang Xiaojie Sun Lili 《China Detergent & Cosmetics》 CAS 2024年第3期50-55,共6页
In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product ... In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product which declares soothing and repair efficacy was used each time in the morning and evening for 4 weeks.Three methods,including visual assessment,image analysis and instrument measurement,were taken to test the related indices of skin redness degree respectively.The improvement of skin redness and the correlation of 3 methods were evaluated by comparing the changes of each index before and after using the product.The results show that the face redness degree score and the image analysis a*value significantly reduce at all time points after using the sample(P<0.05),while the instrument probe a*value significantly reduce at the time point after using for 2 weeks(P<0.05).The correlation coefficient of the face redness degree score and the instrument probe a*value is more than 0.33 and less than 0.67,and the significance level is less than 0.01.Therefore,the sample has soothing and repair efficacy for improving skin redness;and the methods of visual assessment and instrument measurement present moderate positive correlation. 展开更多
关键词 SKIN redness COSMETICS efficacy evaluation CORRELATION
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On Evaluating University Teachers’ Morality and Ethics in the New Era
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作者 LIU Qiu-fen 《Journal of Literature and Art Studies》 2024年第1期92-94,共3页
University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the... University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the fundamental task of cultivating talents.The present study proposes that due to the multiple identities of university teachers,it is necessary to evaluate the construction of teachers’morality and ethics in terms of what to evaluate and how to evaluate?It is expected that the attempt will provide useful guidance for the construction of university teachers’morality and ethics. 展开更多
关键词 university teachers morality and ethics construction evaluATION
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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Approach to evaluating exception handling of programs
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作者 姜淑娟 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期524-528,共5页
To solve the problems that the exception handling code is hard to test and maintain and that it affects the robustness and reliability of software, a method for evaluating the exception handling of programs is present... To solve the problems that the exception handling code is hard to test and maintain and that it affects the robustness and reliability of software, a method for evaluating the exception handling of programs is presented. The exception propagation graph (EPG) that describes the large programs with exception handling constructs is proposed by simplifying the control flow graph and it is applied to a case to verify its validity. According to the EPG, the exception handling code that never executes is identified; the points that are the most critical to controlling exception propagation are found; and the irrational exception handling code is corrected. The constructing algorithm for the EPG is given; thus, this provides a basis for automatically constructing the EPG and automatically correcting the irrational exception handling code. 展开更多
关键词 software robustness exception handling exception propagation evaluating program control flow graph
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A Critical Analysis on Evaluating the Students'Feedback of Learning
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作者 王玲 王云燕 《海外英语》 2012年第9X期104-105,共2页
Teaching involves finding out about students'misunderstandings,intervening to change them and creating a context of learning that encourages students to engage with the subject matter.This theory of making student... Teaching involves finding out about students'misunderstandings,intervening to change them and creating a context of learning that encourages students to engage with the subject matter.This theory of making student learning possible is very much concerned with the content of what students have to learn in relation to how it should be taught.Evaluation implies collecting information about our work,interpreting the information and making judgments about which actions we should take to improve practice.Evaluation is an analytical process that is intrinsic to good teaching. 展开更多
关键词 evaluating FEEDBACK group LEARNING GOOD TEACHING
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Evaluating an EFL Textbook——Twenty-First Century College English
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作者 王海莺 《科技信息》 2008年第28期270-,224,共2页
As a teacher, it is important for us to evaluate, select and adapt teaching materials to meet our teaching and students'learning needs in order to maximize learning potentials. The process of evaluating the teachi... As a teacher, it is important for us to evaluate, select and adapt teaching materials to meet our teaching and students'learning needs in order to maximize learning potentials. The process of evaluating the teaching materials help us make decision in selecting textbooks, as well as allowing us to reflect on our teaching and learning experience. 展开更多
关键词 evaluATION teaching materials SIGNIFICANCE
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On Developing the Questionnaire for Evaluating PBL's Multiple Learning Achievements
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作者 王勃然 《海外英语》 2021年第23期292-293,296,共3页
How to comprehensively,scientifically,objectively and impartially evaluate the multiple learning achievements of the PBL model should be highlighted when PBL is introduced and applied.A questionnaire of a total of 23 ... How to comprehensively,scientifically,objectively and impartially evaluate the multiple learning achievements of the PBL model should be highlighted when PBL is introduced and applied.A questionnaire of a total of 23 items involving such dimensions of language proficiency,subject contents and 21 st Century skills was designed.Its reliability and validity were tested and well-met with the statistical requirements. 展开更多
关键词 PBL multiple learning achievement evaluATION questionnaire development
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Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment 被引量:217
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作者 ZOU Zhi-hong YUN Yi SUN Jing-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期1020-1023,共4页
Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method w... Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable. 展开更多
关键词 water quality evaluation FUZZY weight of evaluating indicator entropy method
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 FUQIANG XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 evaluATION projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations
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Evaluating efficacy of screening for upper gastrointestinal cancer in China:a study protocol for a randomized controlled trial 被引量:13
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作者 Wanqing Chen Hongmei Zeng +8 位作者 Ru Chenl Ruyi Xia Zhixun Yang Changfa Xia Rongshou Zheng Wenqiang Wei Guihua Zhuang Xueqin Yu Jie He 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第4期294-302,共9页
Objective: To evaluate the efficacy and feasibility of screening procedure for upper gastrointestinal cancer in both high-risk and non-high-risk areas in China. Setting: Seven cities/counties, representing three eco... Objective: To evaluate the efficacy and feasibility of screening procedure for upper gastrointestinal cancer in both high-risk and non-high-risk areas in China. Setting: Seven cities/counties, representing three economical-geographical regions (Eastern, Central and Western) in China, were selected as screening centers: three in high-risk areas and four in non-high-risk areas. Participants: Villages/communities in these seven centers regarded as clusters were randomly assigned to either intervention group (screening by endoscopic examination) or control group (with normal community care) in a 1:1 ratio stratified by each center. Eligible participants are local residents aged 40-69 years in the selected villages/communities with no history of cancer or endoscopic examination in the latest 3 years who are mentally and physically competent. Those who are not willing to take endoscopic examination or are unwilling to sign the consent form are excluded from the study. Totally 140,000 participants will be enrolled. Interventions: In high-risk areas of upper gastrointestinal cancer, all subjects in screening group will be screened by endoscopy. In non-high-risk areas, 30% of the subjects in screening group, identified through a survey, will be screened by endoscopy. Primary and secondary outcome measures: The primary outcome is the mortality caused by upper gastrointestinal cancer. The secondary outcomes include detection rate, incidence rate, survival rate, and clinical stage distribution. Additional data on quality of life and cost-effectiveness will also be collected to answer important questions regarding screening effects. Conclusions: Screening strategy evaluated in those areas with positive findings may be promoted nationally and applied to the majority of Chinese people. On the other hand, negative findings will provide scientific evidence for abandoning a test and shifting resources elsewhere. Trial registration: The study has been registered with the Protocol Registration System in Chinese Clinical Trial Registry (identifier: ChiCTR-EOR-16008577). 展开更多
关键词 Randomized controlled trial SCREENING upper gastrointestinal cancer evaluATION China
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A Method for Evaluating the Suitability of CO2 Geological Storage in Deep Saline Aquifers 被引量:4
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作者 LI Fucheng ZHANG Yang +3 位作者 JIA Xiaofeng LI Xufeng JIA Xiaoleng GUO Shengxiu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1838-1851,共14页
This work established an evaluation index system based on a comprehensive analysis of those factors affecting the suitability of CO2 geological storage.This evaluation index system includes three evaluation index laye... This work established an evaluation index system based on a comprehensive analysis of those factors affecting the suitability of CO2 geological storage.This evaluation index system includes three evaluation index layers of geological safety,storage scale and social economy,nine evaluation index sub-layers,and 28 evaluation index factors,and adopts the analytic hierarchy process(AHP)and index overlay methods.Taking the Xining Basin in northwest China as an example,we conducted comprehensive analysis of geological conditions and performed quantitative evaluation based on this evaluation index system,which indicates that the Shuangshu depression of the Xining Basin is comparatively suitable for CO2 geological storage.It is suggested that this evaluation index system and the evaluation method proposed in this study are suitable for most continental sedimentary basins in China and should be widely applied. 展开更多
关键词 CO2 geological storage suitability evaluation evaluation index system AHP Xining Basin
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Challenges of evaluating immunotherapy efficacy in solid tumors 被引量:9
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作者 Rilan Bai Wenqian Li +1 位作者 Nawen Du Jiuwei Cui 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第6期853-861,共9页
Immunotherapy is one of the most promising treatments for multiple tumor types.The significant clinical benefits and durable responses of immunotherapy have led to the emergence of various immune-related clinical resp... Immunotherapy is one of the most promising treatments for multiple tumor types.The significant clinical benefits and durable responses of immunotherapy have led to the emergence of various immune-related clinical response patterns that extend beyond those achieved with cytotoxic agents.Various studies investigated the efficacy of immunotherapy,including the effect on tumor size,long-term survival benefits,and the ability to overcome the particularly challenging survival curves tailing phenomenon.The current immune-related methods guidelines,such as immune-related Response Criteria(irRC),immune-related Response Evaluation Criteria in Solid Tumors(irRECIST),immune Response Evaluation Criteria in Solid Tumors(iRECIST),and immune-modified Response Evaluation Criteria in Solid Tumors(imRECIST),could be well-adapted to identify the heterogeneity of responses that appear in patients receiving immunotherapy,such as pseudoprogression(PsPD)and hyperprogressive disease(HPD),and to some extent to overcome the limitation of evaluating the efficacy of immunotherapy on tumor size by imaging.Additionally,a second type of evaluation method was proposed based on survival,which includes milestone analysis and restricted mean survival time.Currently,milestone analysis is a complementary tool to summarize and interpret trial results along with more conventional measures of survival and other less established metrics.A golden standard evaluation method to distinguish the efficacy of immunotherapy may improve the process of imaging and aid survival-based efficacy evaluation in patients with solid tumors. 展开更多
关键词 NEOPLASMS IMMUNOTHERAPY PSEUDOPROGRESSION response evaluation criteria milestone analysis
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Evaluating Suitability of Multiple Precipitation Products for the Lancang River Basin 被引量:5
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作者 TANG Xiongpeng ZHANG Jianyun +7 位作者 WANG Guoqing YANG Qinli YANG Yanqing GUAN Ti-esheng LIU Cuishan JIN Junliang LIU Yanli BAO Zhenxin 《Chinese Geographical Science》 SCIE CSCD 2019年第1期37-57,共21页
Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sour... Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sources are suitable for all regions or perform the same way in hydrological modeling, so it is essential to test the suitability of precipitation products before applying them. In this study, five widely used global high-resolution precipitation products—Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources(APHRODITE), National Centers for Environmental Prediction Climate Forecast System Reanalysis(NCEP-CFSR), Climate Hazards Group InfraRed Precipitation with Station Data(CHIRPS), China Gauge-based Daily Precipitation Analysis developed by China Meteorological Administration(CMA) and Agricultural Model Intercomparison and Improvement Project based on the NASA Modern-Era Retrospective Analysis for Research and Applications(AgMERRA)—were evaluated using statistical methods and a hydrological approach for their suitability for the Lancang River Basin. The results indicated that APHRODITE, CMA, AgMERRA and CHIRPS were more accurate precipitation indicators than NCEP-CFSR in terms of the multiyear average and seasonal spatial distribution pattern, all of the CHIRPS, Ag MERRA and APHRODITE perform better than CMA and NCEP-CFSR at the small, medium and high precipitation intensities ranges in subbasin11 and sunbabsin46. All five products performed better in subbasin46(a low-altitude region) than in subbasin11(a high-altitude region) on the daily and monthly scales. In addition to NCEP-CFSR, the other four products all presented encouraging potential for streamflow simulation at daily(Yunjinghong) and monthly(Yunjinghong, Jiuzhou and Gajiu) scale. Hydrological simulations forced with APHRODITE were the best of the five for the Yunjinghong station in capturing daily and monthly measured streamflow. Except for NCEP-CFSR, all products were very good for hydrological simulations for the Gajiu and Jiuzhou stations. 展开更多
关键词 MULTIPLE PRECIPITATION PRODUCTS SUITABILITY evaluation the Lancang RIVER BASIN
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Evaluating patients' perception of service quality at hospitals in nine Chinese cities by use of the ServQual scale 被引量:4
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作者 Min Li Douglas Bruce Lowrie +11 位作者 Cheng-Yu Huang Xiang-Chan Lu Ying-Chu Zhu Xing-Hua Wu Mayila Shayiti Qiong-Zhen Tan Hua-Ling Yang Si-Yuan Chen Pan Zhao Sheng-Hua He Xiu-Rong Wang Hong-Zhou Lu 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第6期494-500,共7页
Objective: To investigate patients' perception of service quality at hospitals in nine Chinese cities and propose some measures for improvement. Methods: The ServQ ual scale method was used in a survey involving p... Objective: To investigate patients' perception of service quality at hospitals in nine Chinese cities and propose some measures for improvement. Methods: The ServQ ual scale method was used in a survey involving patients at out-patient and in-patient facilities in Shanghai, Chongqing, Chengdu, Nanning, Guilin and Laibin of Guangxi, Honghezhou of Yunnan, Wulumuqi of Xinjiang and Zhongshan of Guangdong. The data collected were entered and analyzed using SPSS 20.0. Statistical analyses included descriptive statistics, factor analyses, reliability analyses, product-moment correlations, independent-sample t-tests, One-way ANOVA and regression analyses. Results: The Kaiser-Meyer-Olkin value for the factor analysis of the scale was 0.979. The Cronbach's α for the reliability analysis was 0.978. All the Pearson correlation coei cients were positive and statistically signii cant. Visitors to out-patient facilities reported more positive perception tacilities on tangibles(t = 4.168, P(t = 1.979, P <han visitors to in-patient f 0.05). Patients of 60 years of age and above reported mor< 0.001) and reliability e positive perception th<an those between 40 and 49 on reliability(F = 3.311, P = 0.010), assurances(F = 2.751, P 0.05) and empathy(F = 4.009, P = 0.003). For the i ve dimensions of the scale, patients in Laibin, Guangxi reported the most positive perceived service quality, followed by patients in Shanghai. On the other hand, patients in Chongqing and Nanning and Guilin of Guangxi reported relatively poor perceptions of service quality. Standardized regression coei cients showed statistically significant(P < 0.001) positive values for all Serv Qual dimensions. Empathy(β = 0.267) and reliability(β uality. = 0.239) most strongly predicted perception of service qConclusions: Chinese patients perceived service quality as satisfactory. Hospitals in various regions of China should enhance their awareness and ability to serve their patients. 展开更多
关键词 China City HOSPITAL PATIENTS Service Quality evaluation
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A NOVEL PARAMETER FOR EVALUATING THE FATIGUE CRACK GROWTH RATE IN CARBON STEELS 被引量:5
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作者 X.S. Wang1), S.Q. Zhn1), N. Kawagoishi2) and H. Nisitani3) 1) Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China 2) Faculty of Engineering, Kagoshima University, Kagoshima, 890-0065, Japan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第4期271-279,共9页
A novel parameter is suggested for evaluating the fatigue crack growth rate in carbon steels. Fatigue crack propagation tests of an annealed 0.42% carbon steel were carried out under different conditions to investigat... A novel parameter is suggested for evaluating the fatigue crack growth rate in carbon steels. Fatigue crack propagation tests of an annealed 0.42% carbon steel were carried out under different conditions to investigate the relationship between this dominating parameter and the crack opening displacement (COD). A new equation of fatigue crack growth rate is formulated in terms of the suggested parameter. The physical meanings of the material parameters in this equation are explored experimentally. Considering the relation of crack growth and deformation properties, a simple and applicable method is proposed to evaluate the fatigue crack growth rate. It is also observed that the material parameters in the fatigue crack growth rate equation of carbon steels are related linearly to the material strength. The results are in a good agreement with experimental results. 展开更多
关键词 Crack propagation evaluATION Fatigue testing Parameter estimation
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A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China 被引量:19
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作者 YAO Yanbin LIU Dameng TANG Dazhen HUANG Wenhui TANG Shuheng CHE Yao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1253-1270,共18页
Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and meth... Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process (AHP) model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria (including reservoir physical property, storage capacity and geological characteristics), 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank (mean maximum vitrinite reflectance 〉0.5 %) coal districts in China. 展开更多
关键词 coalbed methane reservoir reservoir evaluation reservoir characterization comprehensive model Fuzzy Hierarchy Process Approach (FAHP)
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Analytical method for evaluating stress field in casing-cement-formation system of oil/gas wells 被引量:6
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作者 Wei LIU Baohua YU Jingen DENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第9期1273-1294,共22页
In this paper, we present an analytical method for evaluating the stress field within a casing-cement-formation system of oil/gas wells under anisotropic in-situ stresses in the rock formation and uniform pressure wit... In this paper, we present an analytical method for evaluating the stress field within a casing-cement-formation system of oil/gas wells under anisotropic in-situ stresses in the rock formation and uniform pressure within the casing. The present method treats the in-situ stresses in the formation as initial stresses since the in-situ stresses have already developed in the formation before placement of cement and casing into the well. It is demonstrated that, via this treatment, the present method excludes additional displacements within the formation predicted by the existing method, and gives more reasonable stress results. An actual tight-oil well is analyzed using the present and existing analytical methods, as well as the finite element method. Good agreement between the analytical results and the finite element analysis (FEA) results is obtained, validating the present method. It is also evident that, compared with the present method, the existing method overestimates the compressive stress level within the casing and the cement. Finally, the effects of elastic properties of the formation, cement, and inner pressure of casing on stresses within the casing and cement are illustrated with a series of sensitivity analyses. 展开更多
关键词 near wellbore region stress evaluation anisotropic in-situ stress initialstress
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A new method for evaluating the drought tolerance of upland rice cultivars 被引量:5
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作者 Xiaofeng Zu Yanke Lu +4 位作者 Qianqian Wang Peifeng Chu Wei Miao Huaqi Wang Honggui La 《The Crop Journal》 SCIE CAS CSCD 2017年第6期488-498,共11页
Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought ... Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought tolerance. For breeding purposes, especially for breeding upland rice, it is desirable to develop a simple and accurate method to evaluate rice drought tolerance. We describe a new method that can be used to evaluate efficiently the drought tolerance degree(DTD) of upland rice cultivars, and call it the DTD method.DTD is defined as the mean of the ratios of green leaf length to total leaf length of the top three leaves in every rice seedling after drought treatment, and thus takes values from zero to one. To test whether the DTD method works effectively to evaluate drought tolerance of upland rice cultivars, we determined the DTD values of 13 upland rice cultivars showing varying degrees of drought tolerance in drought-tolerance trials. The idrl-1 mutant, which displayed the strongest drought tolerance of the 13 cultivars as identified by drought-tolerance trials under severe drought stress, had the highest DTD value and297-28, displaying the weakest drought tolerance, had the lowest DTD value. Further analyses of water potential, survival rate, panicles per plant, spikelets per panicle, seed setting rate, yield per plant, and contents of proline, chlorophyll, and malondialdehyde(MDA) indicated that DTD values are in general correlated with the values of these traits,making this new method useful for assessing the drought tolerance of upland rice cultivars.These results show that the DTD method is a simple, direct and relatively accurate evaluation method for drought-tolerance breeding of upland rice. 展开更多
关键词 UPLAND rice BREEDING DROUGHT tolerance degree (DTD) New evaluation method
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Evaluating Common Land Model Energy Fluxes Using FLUXNET Data 被引量:4
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作者 Xiangxiang ZHANG Yongjiu DAI +8 位作者 Hongzhi CUI Robert E.DICKINSON Siguang ZHU Nan WEI Binyan YAN Hua YUAN Wei SHANGGUAN Lili WANG Wenting FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1035-1046,共12页
Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the ... Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the eddy covariance measurements from 20 FLUXNET sites spanning more than 100 site-years were utilized to evaluate the performance of the Common Land Model (CoLM) over different vegetation types in various climate zones. A decomposition method was employed to separate both the observed and simulated energy fluxes, i.e., the sensible heat flux, latent heat flux, net radiation, and ground heat flux, at three timescales ranging from stepwise (30 rain) to monthly. A comparison between the simulations and observations indicated that CoLM produced satisfactory simulations of all four energy fluxes, although the different indexes did not exhibit consistent results among the different fluxes, A strong agreement between the simulations and observations was found for the seasonal cycles at the 20 sites, whereas CoLM underestimated the latent heat flux at the sites with distinct dry and wet seasons, which might be associated with its weakness in simulating soil water during the dry season. CoLM cannot explicitly simulate the midday depression of leaf gas exchange, which may explain why CoLM also has a maximum diurnal bias at noon in the summer. Of the eight selected vegetation types analyzed, CoLM performs best for evergreen broadleaf forests and worst for croplands and wetlands. 展开更多
关键词 model evaluation Common Land Model FLUXNET
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Risk forecasting and evaluating model of Environmental pollution accident 被引量:13
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作者 ZENGWei-hua CHENGSheng-tong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期263-267,共5页
Environmental risk(ER) factors come from ER source and they are controlled by the primary control mechanism(PCM) of environmental risk, due to the self failures or the effects of external environment risk trigger mech... Environmental risk(ER) factors come from ER source and they are controlled by the primary control mechanism(PCM) of environmental risk, due to the self failures or the effects of external environment risk trigger mechanism, the PCM could not work regularly any more, then, the ER factors will release environmental space, and an ER field is formed up. The forming of ER field does not mean that any environmental pollution accident(EPA) will break out; only the ER receptors are exposed in the ER field and damaged seriously, the potential ER really turns into an actual EPA. Researching on the general laws of evolving from environmental risk to EPA, this paper bring forwards a relevant concept model of risk forecasting and evaluating of EPA. This model provides some scientific methods for risk evaluation, prevention and emergency response of EPA. This model not only enriches and develops the theory system of environment safety and emergency response, but also acts as an instruction for public safety, enterprise's safety management and emergency response of the accident. 展开更多
关键词 environmental risk(ER) environmental pollution accident(EPA) ER evaluation ER field EPA damage field
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