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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data 被引量:1
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作者 Yan-Yan Ding Yang-Bo Nie +9 位作者 Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期145-159,共15页
A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°an... A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight method.The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 cm.The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and JEFF-3.3.Based on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were analyzed.The results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results. 展开更多
关键词 Leakage neutron spectra URANIUM D-T neutron source evaluated nuclear data
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Frequency of and reasons behind non-listing in adult patients referred for liver transplantation: Results from a retrospective study
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作者 Marco Biolato Luca Miele +8 位作者 Giuseppe Marrone Claudia Tarli Antonio Liguori Rosaria Calia Giovanni Addolorato Salvatore Agnes Antonio Gasbarrini Maurizio Pompili Antonio Grieco 《World Journal of Transplantation》 2024年第2期99-106,共8页
BACKGROUND Few studies have evaluated the frequency of and the reasons behind the refusal of listing liver transplantation candidates.AIM To assess the ineligibility rate for liver transplantation and its motivations.... BACKGROUND Few studies have evaluated the frequency of and the reasons behind the refusal of listing liver transplantation candidates.AIM To assess the ineligibility rate for liver transplantation and its motivations.METHODS A single-center retrospective study was conducted on adult patients which entailed a formal multidisciplinary assessment for liver transplantation eligibility.The predictors for listing were evaluated using multivariable logistic regression.RESULTS In our center,314 patients underwent multidisciplinary work-up before liver transplantation enlisting over a three-year period.The most frequent reasons for transplant evaluation were decompensated cirrhosis(51.6%)and hepatocellular carcinoma(35.7%).The non-listing rate was 53.8%and the transplant rate was 34.4%for the whole cohort.Two hundred and five motivations for ineligibility were collected.The most common contraindications were psychological(9.3%),cardiovascular(6.8%),and surgical(5.9%).Inappropriate or premature referral accounted for 76(37.1%)cases.On multivariable analysis,a referral from another hospital(OR:2.113;95%CI:1.259–3.548)served as an independent predictor of non-listing.CONCLUSION A non-listing decision occurred in half of our cohort and was based on an inappropriate or premature referral in one case out of three.The referral from another hospital was taken as a strong predictor of non-listing. 展开更多
关键词 Controindication ELIGIBILITY Evaluation REFERRAL Personalized medicine
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How to properly evaluate cardiac vagal tone in oncology studies:a state-of-the-art review
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作者 Pierrick Martinez Marilyne Grinand +2 位作者 Saïda Cheggour Jérôme Taieb Géraud Gourjon 《Journal of the National Cancer Center》 2024年第1期36-46,共11页
Heart rate variability(HRV)analysis provides an assessment of cardiac vagal tone and consequently global cardiac health as well as systemic condition.In systemic diseases such as cancer and during treatments that affe... Heart rate variability(HRV)analysis provides an assessment of cardiac vagal tone and consequently global cardiac health as well as systemic condition.In systemic diseases such as cancer and during treatments that affect the whole body,like chemotherapy,the vagus nerve activity is low and deregulated.Some studies focus on using HRV to predict mortality in oncology.However,in cancer patients,systemic alterations substantially increase artifacts during HRV measurement,especially atrial ectopic beats.Moreover,HRV may be altered by various factors(duration and time of measurement,breathing,drugs,and other confounding factors)that alter each metric in different ways.The Standard Deviation of all Normal to Normal intervals(SDNN)is the most commonly used metric to evaluate HRV in oncology,but it does not appear to be specific to the cardiac vagal tone.Thus,cardiac vagal activity diagnosis and vital prognosis of cancer patients can be biased.Our review presents the main HRV metrics that can be currently used in oncology studies and their links with vagus nerve and cancer.We present the influence of external factors and the required duration and time of measurement.Considering all these parameters,this review proposes seven key points for an assessment of HRV and cardiac vagal tone in patients with cancer. 展开更多
关键词 Clinical oncology Heart rate control Vagal nerve stimulation Autonomic nervous system Evaluation methodology
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight to Evaluate Pond Water Quality 被引量:1
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作者 吴会民 张韦 +4 位作者 梁传辉 樊振中 谢刚 高勇 缴建华 《Agricultural Science & Technology》 CAS 2012年第3期664-668,共5页
[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Meth... [Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp (Cyprinus carpio) as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups. 展开更多
关键词 Water quality Aquaculture pond Fuzzy comprehensive evaluation method Entropy weight
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Insights into spinal muscular atrophy from molecular biomarkers
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作者 Xiaodong Xing Xinzhu Liu +6 位作者 Xiandeng Li Mi Li Xian Wu Xiaohui Huang Ajing Xu Yan Liu Jian Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1849-1863,共15页
Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomar... Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomarker research is currently receiving more attention,and new candidate biomarkers are constantly being discovered.This review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and cons.We also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific biomarkers.This review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future research.Furthermore,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy. 展开更多
关键词 biomarkers disease progression gene-targeting therapy NEUROFILAMENTS Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes
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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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Future of non-invasive graft evaluation:A systematic review of proteomics in kidney transplantation
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作者 Eleni Avramidou Konstantina Psatha +2 位作者 Kallisti St John Georgios Tsoulfas Michalis Aivaliotis 《World Journal of Transplantation》 2025年第1期135-149,共15页
BACKGROUND Despite the developments in the field of kidney transplantation,the already existing diagnostic techniques for patient monitoring are considered insufficient.Protein biomarkers that can be derived from mode... BACKGROUND Despite the developments in the field of kidney transplantation,the already existing diagnostic techniques for patient monitoring are considered insufficient.Protein biomarkers that can be derived from modern approaches of proteomic analysis of liquid biopsies(serum,urine)represent a promising innovation in the monitoring of kidney transplant recipients.AIM To investigate the diagnostic utility of protein biomarkers derived from proteomics approaches in renal allograft assessment.METHODS A systematic review was conducted in accordance with PRISMA guidelines,based on research results from the PubMed and Scopus databases.The primary focus was on evaluating the role of biomarkers in the non-invasive diagnosis of transplant-related com-plications.Eligibility criteria included protein biomarkers and urine and blood samples,while exclusion criteria were language other than English and the use of low resolution and sensitivity methods.The selected research articles,were categorized based on the biological sample,condition and methodology and the significantly and reproducibly differentiated proteins were manually selected and extracted.Functional and network analysis of the selected proteins was performed.RESULTS In 17 included studies,58 proteins were studied,with the cytokine CXCL10 being the most investigated.Biological pathways related to immune response and fibrosis have shown to be enriched.Applications of biomarkers for the assessment of renal damage as well as the prediction of short-term and long-term function of the graft were reported.Overall,all studies have shown satisfactory diagnostic accuracy of proteins alone or in combination with conventional methods,as far as renal graft assessment is concerned.CONCLUSION Our review suggests that protein biomarkers,evaluated in specific biological fluids,can make a significant contribution to the timely,valid and non-invasive assessment of kidney graft. 展开更多
关键词 PROTEOMICS Kidney transplantation Graft evaluation Non-invasive diagnosis Kidney graft function
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Physiology and health assessment,risk balance,and model for endstage liver disease scores:Postoperative outcome of liver transplantation
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作者 Raquel Hohenreuther Andresa ThoméSilveira +4 位作者 Edison Moraes Rodrigues Filho Anderson Garcez Bruna Goularth Lacerda Sabrina Alves Fernandes Claudio Augusto Marroni 《World Journal of Transplantation》 2025年第1期86-94,共9页
BACKGROUND Liver transplantation aims to increase the survival of patients with end-stage liver diseases and improve their quality of life.The number of organs available for transplantation is lower than the demand.To... BACKGROUND Liver transplantation aims to increase the survival of patients with end-stage liver diseases and improve their quality of life.The number of organs available for transplantation is lower than the demand.To provide fair organ distribution,predictive mortality scores have been developed.AIM To compare the Acute Physiology and Chronic Health Evaluation IV(APACHE IV),balance of risk(BAR),and model for end-stage liver disease(MELD)scores as predictors of mortality.METHODS Retrospective cohort study,which included 283 adult patients in the postoperative period of deceased donor liver transplantation from 2014 to 2018.RESULTS The transplant recipients were mainly male,with a mean age of 58.1 years.Donors were mostly male,with a mean age of 41.6 years.The median cold ischemia time was 3.1 hours,and the median intensive care unit stay was 5 days.For APACHE IV,a mean of 59.6 was found,BAR 10.7,and MELD 24.2.The 28-day mortality rate was 9.5%,and at 90 days,it was 3.5%.The 28-day mortality prediction for APACHE IV was very good[area under the curve(AUC):0.85,P<0.001,95%CI:0.76-0.94],P<0.001,BAR(AUC:0.70,P<0.001,95%CI:0.58–0.81),and MELD(AUC:0.66,P<0.006,95%CI:0.55-0.78),P<0.008.At 90 days,the data for APACHE IV were very good(AUC:0.80,P<0.001,95%CI:0.71–0.90)and moderate for BAR and MELD,respectively,(AUC:0.66,P<0.004,95%CI:0.55–0.77),(AUC:0.62,P<0.026,95%CI:0.51–0.72).All showed good discrimination between deaths and survivors.As for the best value for liver transplantation,it was significant only for APACHE IV(P<0.001).CONCLUSION The APACHE IV assessment score was more accurate than BAR and MELD in predicting mortality in deceased donor liver transplant recipients. 展开更多
关键词 Liver transplantation Acute physiology and chronic health evaluation IV Balance of risk Model for end-stage liver disease MORTALITY Intensive care unit
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Large-for-size syndrome prophylaxis in infant liver recipients with low body mass
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作者 Konstantin Semash Timur Dzhanbekov 《World Journal of Transplantation》 2025年第1期72-85,共14页
Transplantation of the left lateral section(LLS)of the liver is now an established practice for treating advanced diffuse and unresectable focal liver diseases in children,with variants of the LLS primarily used in in... Transplantation of the left lateral section(LLS)of the liver is now an established practice for treating advanced diffuse and unresectable focal liver diseases in children,with variants of the LLS primarily used in infants.However,the surgical challenge of matching the size of an adult donor's graft to the volume of a child's abdomen remains significant.This review explores historical developments,various approaches to measuring the required functional liver mass,and techniques to prevent complications associated with large-for-size grafts in infants. 展开更多
关键词 Pediatric liver transplantation Large-for-size syndrome Preoperative evaluation of donor and recipient Liver volumetry Monosegmental transplantation Left lateral sector graft Reduced size liver graft Abdominal wall reconstruction Liver transplantation Liver resection
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“assess”和“evaluate”辨析与翻译
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作者 郑淑明 王文崇 《中国科技术语》 2012年第3期27-32,共6页
assess和evaluate常作为汉语"评估"的英语对应词出现,但其间区别不甚明了。文章从多本词典的释义入手,结合国内外媒体上出现的正误例句,分析两词作"评估"义解时的区别与联系,阐述产生误用的原因,并提出相应的修正意... assess和evaluate常作为汉语"评估"的英语对应词出现,但其间区别不甚明了。文章从多本词典的释义入手,结合国内外媒体上出现的正误例句,分析两词作"评估"义解时的区别与联系,阐述产生误用的原因,并提出相应的修正意见,以期达到规范应用的目的。 展开更多
关键词 assess evaluate 评估 翻译 辨析
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APPLYING PPE MODEL BASED ON RAGA TO CLASSIFYAND EVALUATE SOIL GRADE 被引量:19
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作者 FU Qiang1,2, LU Tie guang2, FU Hong2(1. College of Hydraulic Power, Sichuan University, Chengdu 610065, P.R.China 2. Northeast Agricultural University, Harbin 150030, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2002年第2期136-141,共6页
The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result ... The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result can be influenced by artificial factors. The essentials of fuzzy synthetically judge is to handle the data of high dimension. That is to reducing the dimension number. The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index. But we can′t define whether the weight matrix given by experts is the best projection value or not. So, the authors apply a new technique of falling dimension named projection pursuit to soil study, through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturbance, and acquire preferably effect. Thus, the paper provides a new method to the research of soil classification and grade evaluation. 展开更多
关键词 RAGA PPE soil classification soil evaluation
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Use of a Land Surface Model to Evaluate the Observed Soil Moisture of Grassland at the Tongyu Reference Site 被引量:9
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作者 丹利 季劲钧 刘辉志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1073-1084,共12页
A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), w... A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), was used to evaluate the observation bias of soil moisture (SM) data and analyze the variation of SM at different time scales. The saline-alkaline soil of the grassland at the Tongyu site makes the measured SM too high, especially in boreal summer of 2003-05. The simulated annual mean SM has the lowest value in 2004 and its three-year variation corresponds to the change of precipitation, whereas the observation shows the increasing trend from 2003 to 2005. Compared to the variation range between -60% and 40% for the anomaly percentage of the simulated daily mean SM during May-October of 2004, the measured data show the higher values more than 40%. The magnitude of the variation trend of the observed daily mean SM in 2003 and 2005 is generally consistent with the simulation. The largest deficiency for the soil moisture observation of the grassland is the overestimated value in the drought year with less precipitation. The simulated monthly mean SM has the lowest value in March due to the large contribution of evaporation relative to precipitation and this phenomenon can not be reproduced in the observation. 展开更多
关键词 soil moisture variation trend Tongyu reference site AVIM data evaluation
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Methods to Evaluate and Measure Power of Pneumatic System and Their Applications 被引量:5
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作者 Yan Shi Maolin Cai +1 位作者 Weiqing Xu Yixuan Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期98-108,共11页
Pneumatic system has been widely used throughout industry, and it consumes more than billions kW h of electricity one year all over the world. So as to improve the efficiency of pneumatic system, its power evaluation ... Pneumatic system has been widely used throughout industry, and it consumes more than billions kW h of electricity one year all over the world. So as to improve the efficiency of pneumatic system, its power evaluation as well as measurement methods should be proposed, and their applicability should be validated. In this paper, firstly, power evaluation and measurement methods of pneumatic system were introduced for the first time. Secondly, based on the proposed methods, power distributions in pneumatic system was analyzed. Thirdly, through the analysis on pneumatic efficiencies of typical compressors and pneumatic components, the applicability of the proposed methods were validated. It can be concluded that, first of all, the proposed methods to evaluation and measurement the power of pneumatic system were efficient. Furthermore, the pneumatic power efficiencies of pneumatic system in the air production and cleaning procedure are respectively about 35%–75% and 85%–90%. Moreover, the pneumatic power efficiencies of pneumatic system in the transmission and consumption procedures are about 70%–85% and 10%–35%. And the total pneumatic power efficiency of pneumatic system is about 2%–20%, which varies largely with the system configuration. This paper provides a method to analyze and measure the power of pneumatic system, lay a foundation for the optimization and energy-saving design of pneumatic system. 展开更多
关键词 PNEUMATIC system Compressed AIR ENERGY ASSESSMENT Measurement POWER evaluation
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Patient-reported Outcomes (PROs): An Approach to Evaluate Treatment Efficacy of Chinese Medicine or Integrative Medicine 被引量:14
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作者 赵利 陈金泉 《Chinese Journal of Integrated Traditional and Western Medicine》 2005年第2期151-153,共3页
Chinese medicine (CM) has been an experience based practice over the past three thousand years. The safety and efficacy of CM has been practised through experience, rather than nowadays’ modern scientific measurement... Chinese medicine (CM) has been an experience based practice over the past three thousand years. The safety and efficacy of CM has been practised through experience, rather than nowadays’ modern scientific measurements. In this way, the development of CM has not been keeping pace with the advance in science and technology and the progress in orthodox medicine. In order to meet the requirements of modern science and technology, an evidence based approach must be adopted. Reassurance is needed to convince people for safety and efficacy of CM and give confidence to the evidence based demands ——“Tradition is confirmed by Modern Science” (1) . 展开更多
关键词 Patient-reported Outcomes PROs An Approach to evaluate Treatment Efficacy of Chinese Medicine or Integrative Medicine
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Using Fuzzy Relations and GIS Method to Evaluate Debris Flow Hazard 被引量:10
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作者 SONG Shujun ZHANG Baolei +1 位作者 FENG Wenlan ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期875-881,共7页
The study area, located in the southeast of Tibet along the Sichuan-Tibet highway, is a part of Palongzangbu River basin where mountain hazards take place frequently. On the ground of field surveying, historical data ... The study area, located in the southeast of Tibet along the Sichuan-Tibet highway, is a part of Palongzangbu River basin where mountain hazards take place frequently. On the ground of field surveying, historical data and previous research, a total of 31 debris flow gullies are identified in the study area and 5 factors are chosen as main parameters for evaluating the hazard of debris flows in this study. Spatial analyst functions of geographic information system (GIS) are utilized to produce debris flow inventory and parameter maps. All data are built into a spatial database for evaluating debris flow hazard. Integrated with GIS techniques,the fuzzy relation method is used to calculate the strength of relationship between debris flow inventory and parameters of the database. With this methodology,a hazard map of debris flows is produced. According to this map,6.6% of the study area is classified as very high hazard, 7.3% as high hazard,8.4% as moderate hazard,32. 1% as low hazard and 45.6% as very low hazard or non-hazard areas. After validating the results, this methodology is ultimately confirmed to be available. 展开更多
关键词 fuzzy relations geographic information system (GIS) debris flows hazard evaluation
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Using the concept of ecological groundwater level to evaluate shallow groundwater resources in hyperarid desert regions 被引量:11
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作者 Qi FENG JiaZhong PENG +2 位作者 JianGuo LI HaiYang XI JianHua SI 《Journal of Arid Land》 SCIE 2012年第4期378-389,共12页
This paper, based on the analysis and calculation of the groundwater resources in an arid region from 1980 to 2001, put forward the concept of ecological groundwater level threshold for either salinity control or the ... This paper, based on the analysis and calculation of the groundwater resources in an arid region from 1980 to 2001, put forward the concept of ecological groundwater level threshold for either salinity control or the determination of ecological warning. The surveys suggest that soil moisture and soil salinity are the most important environmental factors in determining the distribution and changes in vegetation. The groundwater level threshold of ecological warning can be determined by using a network of groundwater depth observation sites that monitor the environmental moisture gradient as reflected by plant physiological characteristics. According to long-term field observations within the Ejin oases, the groundwater level threshold for salinity control varied between 0.5 m and 1.5 m, and the ecological warning threshold varied between 3.5 m and 4.0 m. The quantity of groundwater re- sources (renewable water resources, ecological water resources, and exploitable water resources) in arid areas can be calculated from regional groundwater level information, without localized hydrogeological data. The concept of groundwater level threshold of ecological warning was established according to water development and water re- sources supply, and available groundwater resources were calculated. The concept not only enriches and broadens the content of groundwater studies, but also helps in predicting the prospects for water resources development. 展开更多
关键词 evaluation water resources Ejin oasis ecological groundwater level groundwater level threshold of ecologicalwarning
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Methodology to Evaluate Fatigue Damage of High-Speed Train Welded Bogie Frames Based on On-Track Dynamic Stress Test Data 被引量:5
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作者 Guangxue Yang Meng Wang +1 位作者 Qiang Li Ran Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期181-188,共8页
The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. ... The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. In this paper, a new method was established to compute the equivalent stress amplitude to evaluate the fatigue damage based on the measurable randomness, since the equivalent stress is the key parameter for assessment of structure fatigue life and load derivation. The equivalent stress amplitude of a high-speed train welded bogie frame was found to obey normal distribution under uniform operation route that verified by on-track dynamic stress data, and the proposed model is, in effect, an improved version of the mathematical model used to calculate the equivalent stress amplitude. The data of a long-term, on-track dynamic stress test program was analyzed to find that the normal distribution parameters of equivalent stress amplitude values differ across different operation route. Thus, the fatigue damage of the high-speed train welded bogie frame can be evaluated by the proposed method if the running schedule of the train is known a priori. The results also showed that the equivalent stress amplitude of the region connected to the power system is more random than in other regions of the bogie frame. 展开更多
关键词 Fatigue damage evaluation Equivalent STRESS amplitude On-track dynamic STRESS test Welded BOGIE frame of high-speed TRAIN
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A deep reinforcement learning(DRL)based approach for well-testing interpretation to evaluate reservoir parameters 被引量:6
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作者 Peng Dong Zhi-Ming Chen +1 位作者 Xin-Wei Liao Wei Yu 《Petroleum Science》 SCIE CAS CSCD 2022年第1期264-278,共15页
Parameter inversions in oil/gas reservoirs based on well test interpretations are of great significance in oil/gas industry.Automatic well test interpretations based on artificial intelligence are the most promising t... Parameter inversions in oil/gas reservoirs based on well test interpretations are of great significance in oil/gas industry.Automatic well test interpretations based on artificial intelligence are the most promising to solve the problem of non-unique solution.In this work,a new deep reinforcement learning(DRL)based approach is proposed for automatic curve matching for well test interpretation,by using the double deep Q-network(DDQN).The DDQN algorithms are applied to train agents for automatic parameter tuning in three conventional well-testing models.In addition,to alleviate the dimensional disaster problem of parameter space,an asynchronous parameter adjustment strategy is used to train the agent.Finally,field applications are carried out by using the new DRL approaches.Results show that step number required for the DDQN to complete the curve matching is the least among,when comparing the naive deep Q-network(naive DQN)and deep Q-network(DQN).We also show that DDQN can improve the robustness of curve matching in comparison with supervised machine learning algorithms.Using DDQN algorithm to perform 100 curve matching tests on three traditional well test models,the results show that the mean relative error of the parameters is 7.58%for the homogeneous model,10.66%for the radial composite model,and 12.79%for the dual porosity model.In the actual field application,it is found that a good curve fitting can be obtained with only 30 steps of parameter adjustment. 展开更多
关键词 Well testing Deep reinforcement learning Automatic interpretation Parameter evaluation
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Benchmarking of JEFF-3.2, FENDL-3.0 and TENDL-2014 evaluated data for tungsten with 14.8 MeV neutrons 被引量:5
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作者 Suyalatu Zhang Yang-Bo Nie +6 位作者 Jie Ren Fei Luo Xi-Chao Ruan Zhi-Qiang Chen Rui Han Temuerbagen Bao Si-Miao Ge 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第3期1-6,共6页
Integral experiments on tungsten slab samples were carried out on the D-T neutron source facility at China Institute of Atomic Energy. Leakage neutron spectra from the irradiated tungsten target were measured by the t... Integral experiments on tungsten slab samples were carried out on the D-T neutron source facility at China Institute of Atomic Energy. Leakage neutron spectra from the irradiated tungsten target were measured by the time-of-flight technique. Accuracy of the nuclear data for tungsten was examined by comparing the measured neutron spectra with the leakage neutron spectra simulated using the MCNP-4C code with evaluated nuclear data of the JEFF-3.2, FENDL-3.0 and TENDL-2014 libraries. The results show that the calculations with JEFF-3.2 agree well with the measurements in the whole energy range and all angles, whereas the spectra calculated with FENDL-3.0 and TENDL-2014 have some discrepancies with the experimental data. 展开更多
关键词 Integral experiment D-T NEUTRON source TIME-OF-FLIGHT technique Leakage NEUTRON spectrum Monte Carlo simulation evaluated nuclear data
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Use of Farmers’ Indicators to Evaluate the Sustainability of Cropping Systems on Sloping Land in Yunnan Province, China 被引量:4
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作者 M. SUBEDI T. J. HOCKING +4 位作者 M. A. FULLEN A, R. McCREA E. MILNE WU Bo-Zhi D. Jo MITCHELL 《Pedosphere》 SCIE CAS CSCD 2009年第3期344-355,共12页
Diversity in the biophysical and socio-economic attributes of agricultural systems makes them uniquely niche based. Farmers are expert in local biophysical and socio-economic situations and can contribute in developin... Diversity in the biophysical and socio-economic attributes of agricultural systems makes them uniquely niche based. Farmers are expert in local biophysical and socio-economic situations and can contribute in developing pragmatic indicators of agro-environmental development. During evaluation of an agricultural research project in Yunnan, China, local farmers were capable of evaluating the effects of modified technologies on existing cropping systems and discussed their attitudes to the interventions using their own indicators. Farmers' response can be grouped into seven major aspects: i) effects on income, ii) effects on production resources, iii) effects on crop management, iv) existing local knowledge about the technology, v) availability of inputs, vi) access to information, and vii) socio-economic conditions of farming households. Farmers concluded that environmental conditions in the experimental catchment in comparison to an adjacent untreated catchment were better in terms of soil and water losses, vegetation cover and natural resources, infrastructures and catchment management, use of environmentally-friendly technologies, and crop productivity. Success in soil and water conservation programmes depends on the efforts of the farmers and other local users and their greater involvement helps to identify more pragmatic indicators. Furthermore, it increases ownership of the programme, enhances interactions with the project scientists, increases farmers' awareness of ago-environmental problems and their possible consequences. These development will enable scientists to develop better targeted interventions and increase the likelihood of adoption of tested technologies by local communities. The use of paired adjacent catchments improved evaluation activities and is proposed as good practice for future catchment improvement programmes. 展开更多
关键词 agro-environmental sustainability China farmers' evaluation farmers' indicator paired catchments
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