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A Model Comparison Study of Fragment Production in 140 A MeV 58,64Ni+9Be Reactions
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作者 马春旺 张艳丽 +1 位作者 王闪闪 乔春源 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期29-33,共5页
The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion... The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion- ablation (SAA) model, and the empirical EPAX2/EPAX3 formulae. The Gogny-gO interaction is taken as the effective nucleon-nucleon interaction in the AMD calculation, and the decays of fragments obtained from the AMD results are calculated by using the GEMINI code. The calculated cross sections of fragments are compared. 展开更多
关键词 BE A model comparison Study of Fragment Production in 140 A MeV REACTIONS AMD NI
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Software Testing Method Based on Model Comparison
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作者 谢晓东 卢炎生 毛澄印 《Journal of Southwest Jiaotong University(English Edition)》 2008年第2期99-108,共10页
A model comparison based software testing method (MCST) is proposed. In this method, the requirements aria programs or software under test are transformed into the ones in the same form, and described by the same mo... A model comparison based software testing method (MCST) is proposed. In this method, the requirements aria programs or software under test are transformed into the ones in the same form, and described by the same model describe language (MDL). Then, the requirements are transformed into a specification model and the programs into an implementation model. Thus, the elements and structures of the two models are compared, and the differences between them are obtained. Based on the diffrences, a test suite is generated. Different MDLs can be chosen for the software under test. The usages of two classical MDLs in MCST, the equivalence classes model and the extended finite state machine (EFSM) model, are described with example applications. The results show that the test suites generated by MCST are more efficient and smaller than some other testing methods, such as the pathcoverage testing method, the object state diagram testing method, etc. 展开更多
关键词 Software testing Test suite generation model comparison
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Comparison on Winter Wheat Yield Estimating Models Based on Radarsat-2 and HJ Satellite in Huaihe River Region 被引量:1
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作者 范伟 陈磊 +2 位作者 陈娟 闫洪凯 刘韬 《Agricultural Science & Technology》 CAS 2016年第4期1019-1023,共5页
The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model... The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model. With Shou County and Huaiyuan County of Anhui Province as the experimental fields of winter wheat producing areas, the linear winter wheat yield estimating models were established by adopting backscattering coefficient and Normalized Difference Vegetation Index(NDVI) based on images from the synthetic aperture radar(SAR)—RDARSAT-2 and HJ satellite photographed in mid-April and early May, 2014, and then comparisons were conducted on the accuracy of the yield estimating models. The accuracies of the yield estimating models established using co-polarized(HH) and cross-polarized(HV) modes of SAR in Jiangou Town, Shou County were 68.37% and 74.01%, respectively, while the accuracies in Longkang Town, Huaiyuan County were 63.10%and 69.10%, respectively. Accuracies of yield estimating models established by HJ satellite data were 69.52% and 66.43% in Shou County and Huaiyuan County, respectively. Accuracies of winter yield estimating model based on HJ satellite data and that based on SAR were closed, and the yield difference of winter wheat in the lodging region was analyzed in detail. The model results laid the foundation and accumulated experience for the verification, parameters correction and promotion of the winter wheat yield estimating model. 展开更多
关键词 Winter wheat yield estimating model Synthetic aperture radar RADARSAT-2 HJ satellite model comparison
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Accuracy comparison of dry matter intake prediction models evaluated by a feeding trial of lactating dairy cows fed two total mixed rations with different forage source 被引量:4
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作者 PAN Xiao-hua YANG Liang +2 位作者 Yves Beckers XIONG Ben-hai JIANG Lin-shu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第4期921-929,共9页
Dry matter intake (DMI) prediction models of NRC (2001), Fox et aL (2004) and Fuentes-Pila et aL (2003) were targeted in the present study, and the objective was to evaluate their prediction accuracy with feed... Dry matter intake (DMI) prediction models of NRC (2001), Fox et aL (2004) and Fuentes-Pila et aL (2003) were targeted in the present study, and the objective was to evaluate their prediction accuracy with feeding trial data of 32 lactating Holstein cows fed two total mixed rations with different forage source. Thirty-two cows were randomly assigned to one of two total mixed ration groups: a ration containing a mixed forage (MF) of 3.7% Chinese wildrye, 28.4% alfalfa hay and 26.5% corn silage diet and another ration containing 33.8% corn stover (CS) as unique forage source. The actual DMI was greater in MF group than in CS group (P=0.064). The NRC model to predict DMI resulted in the lowest root mean square prediction error for both MF and CS groups (1.09 kg d-1 vs. 1.28 kg d-1) and the highest accuracy and precision based on concordance correlation coefficient for both MF and CS diet (0.89 vs. 0.87). Except the NRC model, the other two models presented mean and linear biases in both MF and CS diets when prediction residuals were plotted against predicted DMI values (P〈0.001). The DMI variation in MF was caused by week of lactation (55.6%), milk yield (13.9%), milk fat percentage (7.1%) and dietary neutral detergent fiber (13.3%), while the variation in CS was caused by week of lactation (50.9%), live body weight (28.2%), milk yield (8.4%), milk fat percentage (5.2%) and dietary neutral detergent fibre (3.8%). In a brief, the NRC model to predict DMI is comparatively acceptable for lactating dairy cows fed two total mixed rations with different forage source. 展开更多
关键词 dairy cows dry matter intake model comparison mixed forage corn stover
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Comparison of three mathematical prediction models in patients with a solitary pulmonary nodule 被引量:9
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作者 Xuan Zhang Hong-Hong Yan +4 位作者 Jun-Tao Lin Ze-Hua Wu Jia Liu Xu-Wei Cao Xue-Ning Yang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第6期647-652,共6页
Background: Effective methods for managing patients with solitary pulmonary nodules(SPNs) depend critically on the predictive probability of malignancy.Methods: Between July 2009 and June 2011, data on gender, age... Background: Effective methods for managing patients with solitary pulmonary nodules(SPNs) depend critically on the predictive probability of malignancy.Methods: Between July 2009 and June 2011, data on gender, age, cancer history, tumor familial history, smoking status, tumor location, nodule size, spiculation, calcification, the tumor border, and the final pathological diagnosis were collected retrospectively from 154 surgical patients with an SPN measuring 3-30 mm. Each final diagnosis was compared with the probability calculated by three predicted models—the Mayo, VA, and Peking University(PU) models. The accuracy of each model was assessed using area under the receiver operating characteristics(ROC) and calibration curves.Results: The area under the ROC curve of the PU model [0.800; 95% confidence interval(CI): 0.708-0.891] was higher than that of the Mayo model(0.753; 95% CI: 0.650-0.857) or VA model(0.728; 95% CI: 0.623-0.833); however, this finding was not statistically significant. To varying degrees, calibration curves showed that all three models overestimated malignancy.Conclusions: The three predicted models have similar accuracy for prediction of SPN malignancy, although the accuracy is not sufficient. For Chinese patients, the PU model may has greater predictive power.Background: Here, we introduced our short experience on the application of a new CUSA Excel ultrasonic aspiration system, which was provided by Integra Lifesciences corporation, in skull base meningiomas resection.Methods: Ten patients with anterior, middle skull base and sphenoid ridge meningioma were operated using the CUSA Excel ultrasonic aspiration system at the Neurosurgery Department of Shanghai Huashan Hospital from August 2014 to October 2014. There were six male and four female patients, aged from 38 to 61 years old(the mean age was 48.5 years old). Five cases with tumor located at anterior skull base, three cases with tumor on middle skull base, and two cases with tumor on sphenoid ridge.Results: All the patents received total resection of meningiomas with the help of this new tool, and the critical brain vessels and nerves were preserved during operations. All the patients recovered well after operation.Conclusions: This new CUSA Excel ultrasonic aspiration system has the advantage of preserving vital brain arteries and cranial nerves during skull base meningioma resection, which is very important for skull base tumor operations. This key step would ensure a well prognosis for patients. We hope the neurosurgeons would benefit from this kind of technique.Background: The purposes of this study were to explore the effects of high mobility group protein box 1(HMGB1) gene on the growth, proliferation, apoptosis, invasion, and metastasis of glioma cells, with an attempt to provide potential therapeutic targets for the treatment of glioma. Methods: The expressions of HMGB1 in glioma cells(U251, U-87 MG and LN-18) and one control cell line(SVG p12) were detected by real time PCR and Western blotting, respectively. Then, the effects of HMGB1 on the biological behaviors of glioma cells were detected: the expression of HMGB1 in human glioma cell lines U251 and U-87 MG were suppressed using RNAi technique, then the influences of HMGB1 on the viability, cycle, apoptosis, and invasion abilities of U251 and U-87 MG cells were analyzed using in a Transwell invasion chamber. Also, the effects of HMGB1 on the expressions of cyclin D1, Bax, Bcl-2, and MMP 9 were detected. Results: As shown by real-time PCR and Western blotting, the expression of HMGB1 significantly increased in glioma cells(U251, U-87 MG, and LN-18) in comparison with the control cell line(SVG p12); the vitality, proliferation and invasive capabilities of U251 and U-87 MG cells in the HMGB1 siR NA-transfected group were significantly lower than those in the blank control group and negative control(NC) siR NA group(P〈0.05) but showed no significant difference between the blank control group and NC siR NA group. The percentage of apoptotic U251 and U-87 MG cells was significantly higher in the HMGB1 siR NA-transfected group than in the blank control group and NC siR NA group(P〈0.05) but was similar between the latter two groups. The HMGB1 siR NA-transfected group had significantly lower expression levels of Cyclin D1, Bcl-2, and MMP-9 protein in U251 and U-87 MG cells and significantly higher expression of Bax protein than in the blank control group and NC siR NA group(P〈0.05); the expression profiles of cyclin D1, Bax, Bcl-2, and MMP 9 showed no significant change in both blank control group and NC siR NA group. Conclusions: HMGB1 gene may promote the proliferation and migration of glioma cells and suppress its effects of apoptosis. Inhibition of the expression of HMGB1 gene can suppress the proliferation and migration of glioma cells and promote their apoptosis. Our observations provided a new target for intervention and treatment of glioma. 展开更多
关键词 Solitary pulmonary nodule(SPN) benign and malignant model comparison
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Comparison of Ten Potential Evapotranspiration Models and Their Attribution Analyses for Ten Chinese Drainage Basins 被引量:2
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作者 Ruiheng XIE Aihui WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第9期959-974,共16页
Potential evapotranspiration(EPET)is usually calculated by empirical methods from surface meteorological variables,such as temperature,radiation and wind speed.The in-situ measured pan evaporation(ETpan)can also be us... Potential evapotranspiration(EPET)is usually calculated by empirical methods from surface meteorological variables,such as temperature,radiation and wind speed.The in-situ measured pan evaporation(ETpan)can also be used as a proxy for EPET.In this study,EPET values computed from ten models are compared with observed ETpan data in ten Chinese river basins for the period 1961−2013.The daily observed meteorological variables at 2267 stations are used as the input to those models,and a ranking scheme is applied to rank the statistical quantities(ratio of standard deviations,correlation coefficient,and ratio of trends)between ETpan and modeled EPET in different river basins.There are large deviations between the modeled EPET and the ETpan in both the magnitude and the annual trend at most stations.In eight of the basins(except for Southeast and Southwest China),ETpan shows decreasing trends with magnitudes ranging between−0.01 mm d−1 yr−1 and−0.03 mm d−1 yr−1,while the decreasing trends in modeled EPET are less than−0.01 mm d−1 yr−1.Inter comparisons among different models in different river basins suggest that PETHam1 is the best model in the Pearl River basin,PETHam2 outperforms other models in the Huaihe River,Yangtze River and Yellow River basins,and PETFAO is the best model for the remaining basins.Sensitivity analyses reveal that wind speed and sunshine duration are two important factors for decreasing EPET in most basins except in Southeast and Southwest China.The increasing EPET trend in Southeast China is mainly attributed to the reduced relative humidity. 展开更多
关键词 potential evapotranspiration model pan evaporation model comparison sensitivity analysis China
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Comparison of coupled and uncoupled models in simulating Monsoon Intraseasonal Oscillation from CMIP6
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作者 Baosheng Li Dake Chen +1 位作者 Tao Lian Jianhuang Qin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第10期100-108,共9页
The monsoon intraseasonal oscillation(MISO)is the dominant variability over the Indian Ocean during the Indian summer monsoon(ISM)season and is characterized by pronounced northward propagation.Previous studies have s... The monsoon intraseasonal oscillation(MISO)is the dominant variability over the Indian Ocean during the Indian summer monsoon(ISM)season and is characterized by pronounced northward propagation.Previous studies have shown that general circulation models(GCMs)still have difficulty in simulating the northwardpropagating MISO,and that the role of air-sea interaction in MISO is unclear.In this study,14 atmosphere-ocean coupled GCMs(CGCMs)and the corresponding atmosphere-only GCMs(AGCMs)are selected from Phase 6 of the Coupled Model Intercomparison Project(CMIP6)to assess their performance in reproducing MISO and the associated vortex tilting mechanism.The results show that both CGCMs and AGCMs are able to well simulate the significant relationship between MISO and vortex tilting.However,80%of CGCMs show better simulation skills for MISO than AGCMs in CMIP6.In AGCMs,the poor model fidelity in MISO is due to the failure simulation of vortex tilting.Moreover,it is found that failure to simulate the downward motion to the north of convection is responsible for the poor simulation of vortex tilting in AGCMs.In addition,it is observed that there is a significant relationship between the simulated sea surface temperature gradient and simulated vertical velocity shear in the meridional direction.These findings indicate that air-sea interaction may play a vital role in simulating vertical motions in tilting and MISO processes.This work offers us a specific target to improve the MISO simulation and further studies are needed to elucidate the physical processes of this air-sea interaction coupling with vortex tilting. 展开更多
关键词 monsoon intraseasonal oscillation(MISO) model comparison vortex tilting CMIP6
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A Brief Analysis of the New Translation-comparison Model——from the View of Assimilation and Accommodation
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作者 佘阿莉 《教师》 2017年第35期48-49,共2页
关键词 NEW translation-comparison model ASSIMILATION ACCOMMODATION
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Comparison of Crop Model Validation Methods 被引量:3
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作者 CAO Hong-xin Jim Scott Hanan +11 位作者 LIU Yan LIU Yong-xia YUE Yan-bin ZHU Da-wei LU Jian- fei SUNJin-ying SHI Chun-lin GE Dao-kuo WEI Xiu-fang YAO An-qing TIAN Ping-ping BAO Tai-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第8期1274-1285,共12页
In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean... In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean observation), r (correlation), and R2 (determination coefficient), are compared for the same rice architectural parameter model, and their advantages and disadvantages are analyzed. A new index for validation of crop models, dap between the observed and the simulated values, is proposed, with dap〈5% as the suggested standard for precision of crop models. The different kinds of validation methods in crop models should be combined in the following aspects:(1) calculating da and dap; (2) calculating the RMSE or Sd; (3) calculating r and R2, at the same time, plotting 1:1 diagram. 展开更多
关键词 crop models validation methods comparison
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The Comparison between Jerome Model and Horace Model
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作者 吴晓丽 《海外英语》 2013年第11X期170-172,共3页
Jerome Model and Horace Model are the two influential translation models in the translation field. This article tries to find the similarities and differences between these two models.
关键词 Jerome model HORACE model comparison
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Comparison of Ruin Probabilities in Compound Poisson Risk Model
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作者 Dol Nath Khanal 《Open Journal of Statistics》 2019年第1期41-47,共7页
Compound Poisson risk model has been simulated. It has started with exponential claim sizes. The simulations have checked for infinite ruin probabilities. An appropriate time window has been chosen to estimate and com... Compound Poisson risk model has been simulated. It has started with exponential claim sizes. The simulations have checked for infinite ruin probabilities. An appropriate time window has been chosen to estimate and compare ruin probabilities. The infinite ruin probabilities of two-compound Poisson risk process have estimated and compared them with standard theoretical results. 展开更多
关键词 COMPOUND POISSON RISK model RUIN Probabilities comparison Simulations THEORETICAL Results
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A Model of Cloud-Based Enterprise Resource Planning (ERP) for Small and Medium Enterprise
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作者 Mohammad Jahangir Alam Shoman Das Sharma Tanjia Chowdhury 《Journal of Computer and Communications》 2024年第10期37-50,共14页
Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced fe... Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced features of cloud computing, such as SaaS, PaaS and IaaS service models. So, nowadays, many organizations are trying to implement Cloud Computing based ERP system to enjoy the benefits of cloud computing. To implement any ERP system, an organization usually faces many challenges. As a result, this research has introduced how easily this cloud system can be implemented in an organization. By using this ERP system, an organization can be benefited in many ways;especially Small and Medium Enterprises (SMEs) can enjoy the highest possible benefits from this system. 展开更多
关键词 Cloud Computing Cloud comparison Cloud models Enterprise Resource planning (ERP) Small and Medium Enterprise (SME)
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A Weighted Goal Programming Model for the DASH Diet Problem: Comparison with the Linear Programming DASH Diet Model
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作者 Anayo Charles Iwuji Emeka Uchendu Agwu 《American Journal of Operations Research》 2017年第5期307-322,共16页
A Linear Programming DASH diet model for persons with hypertension has previously been formulated and daily minimum cost diet plans that satisfy the DASH diets’ tolerable intake level of the nutrients for 1500 mg a d... A Linear Programming DASH diet model for persons with hypertension has previously been formulated and daily minimum cost diet plans that satisfy the DASH diets’ tolerable intake level of the nutrients for 1500 mg a day Sodium level and different daily calorie levels were obtained using sample foods from the DASH diet eating plan chart. But the limitation in the use of linear programming model in selecting diet plans to meet specific nutritional requirements which normally results in the oversupply of certain nutrients was evident in the linear programming DASH diet plan obtained as the nutrient level of the diet plans obtained had wide deviations of from the DASH diets’ tolerable upper and lower intake level for the given calorie and sodium levels. Hence the need for a model that gives diet plans with minimized nutrients’ level deviations from the DASH diets’ tolerable intake level for different daily calorie and sodium level at desired cost. A weighted Goal Programming DASH diet model that minimizes the daily cost of the DASH eating plan as well as deviations of the diets’ nutrients content from the DASH diet’s tolerable intake levels is hereby presented in this work. The formulated weighted goal programming DASH diet model is further illustrated using chosen sample foods from the DASH food chart as used in the work on the linear programming DASH diet model for a 1500 mg sodium level and 2000 calories a day diet plan as well as for 1800, 2200, 2400, 2600, 2800 and 3000 daily calorie levels. A comparison of the DASH nutrients’ composition of the weighted Goal Programming DASH diet plans and those of the linear programming DASH diet plans were carried out at this sodium level and the different daily calorie levels. It was evident from the results of the comparison that the weighted goal programming DASH diet plans has minimized deviations from the DASH diet’s tolerable intake levels than those of the linear programming DASH diet plans. 展开更多
关键词 DASH (Dietary Approaches to Stop Hypertension) DIET model HYPERTENSION DIET model Minimum Nutrient Deviation DIET Plan WEIGHTED GOAL PROGRAMMING DIET model Linear and GOAL PROGRAMMING comparison
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Feature Modeling and Variability Modeling Syntactic Notation Comparison and Mapping
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作者 Wahyudianto   Eko K. Budiardjo Elviawaty M. Zamzami 《Journal of Computer and Communications》 2014年第2期101-108,共8页
Feature Model (FM) became an important role in Software Product Line Engineering (SPLE) field. Many approaches have been introduced since the original FM came up with Feature Oriented Domain Analysis (FODA) introduced... Feature Model (FM) became an important role in Software Product Line Engineering (SPLE) field. Many approaches have been introduced since the original FM came up with Feature Oriented Domain Analysis (FODA) introduced by Kang in 1990. The main purpose of FM is used for commonality and variability analysis in domain engineering, to optimize the reusable aspect of software features or components. Cardinality-based Feature Model (CBFM) is one extension of original FM, which integrates several notations of other extensions. In CBFM, feature model defined as hierarchy of feature, with each of feature has a cardinality. The other notation to express variability within SPLE is Orthogonal Variability Model (OVM). At the other hand, OMG as standard organization makes an effort to build standard generic language to express the commonality and variability in SPL field, by initiate Common Variability Language (CVL). This paper reports the comparison and mapping of FODA, CBFM and OVM to CVL where need to be explored first to define meta model mapping of these several approaches. Furthermore, the comparison and mapping of those approaches are discussed in term of R3ST (read as “REST”) software feature model as the case study. 展开更多
关键词 comparison and MAPPING FODA Cardinality-based FEATURE model Orthogonal VARIABILITY LANGUAGE Common VARIABILITY LANGUAGE FEATURE model R3ST Software
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A comparative study of seismic tomography models of the Chinese continental lithosphere 被引量:5
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作者 Xuezhen Zhang Xiaodong Song Jiangtao Li 《Earthquake Science》 2022年第3期161-185,共25页
The Chinese mainland is subject to complicated plate interactions that give rise to its complex structure and tectonics. While several seismic velocity models have been developed for the Chinese mainland, apparent dis... The Chinese mainland is subject to complicated plate interactions that give rise to its complex structure and tectonics. While several seismic velocity models have been developed for the Chinese mainland, apparent discrepancies exist and, so far, little effort has been made to evaluate their reliability and consistency. Such evaluations are important not only for the application and interpretation of model results but also for future model improvement. To address this problem, here we compare five published shear-wave velocity models with a focus on model consistency. The five models were derived from different datasets and methods (i.e., body waves, surface waves from earthquakes, surface waves from noise interferometry, and full waves) and interpolated into uniform horizontal grids (0.5° × 0.5°) with vertical sampling points at 5 km, 10 km, and then 20 km intervals to a depth of 160 km below the surface, from which we constructed an averaged model (AM) as a common reference for comparative study. We compare both the absolute velocity values and perturbation patterns of these models. Our comparisons show that the models have large (> 4%) differences in absolute values, and these differences are independent of data coverage and model resolution. The perturbation patterns of the models also show large differences, although some of the models show a high degree of consistency within certain depth ranges. The observed inconsistencies may reflect limited model resolution but, more importantly, systematic differences in the datasets and methods employed. Thus, despite several seismic models being published for this region, there is significant room for improvement. In particular, the inconsistencies in both data and methodologies need to be resolved in future research. Finally, we constructed a merged model (ChinaM-S1.0) that incorporates the more robust features of the five published models. As the existing models are constrained by different datasets and methods, the merged model serves as a new type of reference model that incorporates the common features from the joint datasets and methods for the shear-wave velocity structure of the Chinese mainland lithosphere. 展开更多
关键词 Chinese mainland shear-wave velocity model model comparison continental lithosphere
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A comparative study of seismic tomography models of Southwest China 被引量:1
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作者 Xuezhen Zhang Xiaodong Song Feiyi Wang 《Earthquake Science》 2023年第1期15-39,共25页
The margin of the Tibetan Plateau of Southwest China is one of the most seismically active regions of China and is the location of the China Seismic Experimental Site(CSES).Many studies have developed seismic velocity... The margin of the Tibetan Plateau of Southwest China is one of the most seismically active regions of China and is the location of the China Seismic Experimental Site(CSES).Many studies have developed seismic velocity models of Southwest China,but few have compared and evaluated these models which is important for further model improvement.Thus,we compared six published seismic shear-wave velocity models of Southwest China on absolute velocity and velocity perturbation patterns.The models are derived from different types of data(e.g.,surface waves from ambient noise and earthquakes,body-wave travel times,receiver functions) and inversion methods.We interpolated the models into a uniform horizontal grid(0.5° × 0.5°) and vertically sampled them at 5,10,20,30,40,and 60 km depths.We found significant differences between the six models.Then,we selected three of them that showed greater consistency for further comparison.Our further comparisons revealed systematic biases between models in absolute velocity that may be related to different data types.The perturbation pattern of the model is especially divergent in the shallow part,but more consistent in the deep part.We conducted synthetic and inversion tests to explore possible causes and our results imply that systematic differences between the data,differences in methods,and other factors may directly affect the model.Therefore,the Southwest China velocity model still has considerable room for improvement,and the impact of inconsistency between different data types on the model needs further research.Finally,we proposed a new reference shear-wave velocity model of Southwest China(SwCM-S1.0) based on the three selected models with high consistency.We believe that this model is a better representation of more robust features of the models that are based on different data sets. 展开更多
关键词 model comparison shear-wave velocity model Southwest China
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Analysis of the Resolution of Crime Using Predictive Modeling 被引量:1
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作者 Keshab R. Dahal Jiba N. Dahal +1 位作者 Kenneth R. Goward Oluremi Abayami 《Open Journal of Statistics》 2020年第3期600-610,共11页
There has been evidence of crime in the US since colonization. In this article, we analyze the crime statistics of San Francisco and its resolution of crime recorded from January to September of the year 2018. We defi... There has been evidence of crime in the US since colonization. In this article, we analyze the crime statistics of San Francisco and its resolution of crime recorded from January to September of the year 2018. We define resolution of crime as a target variable and study its relationship with other variables. We make several classification models to predict resolution of crime using several data mining techniques and suggest the best model for predicting resolution. 展开更多
关键词 Machine Learning Classification model comparison Predictive modeling Resolution of Crime
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Classification of Acupuncture Points Based on the Bert Model*
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作者 Xi Zhong Yangli Jia +1 位作者 Dekui Li Xiangliang Zhang 《Journal of Data Analysis and Information Processing》 2021年第3期123-135,共13页
In this paper, we explore the multi-classification problem of acupuncture acupoints bas</span><span><span style="font-family:Verdana;">ed on </span><span style="font-family:Ve... In this paper, we explore the multi-classification problem of acupuncture acupoints bas</span><span><span style="font-family:Verdana;">ed on </span><span style="font-family:Verdana;">Bert</span><span style="font-family:Verdana;"> model, </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;">, we try to recommend the best main acupuncture point for treating the disease by classifying and predicting the main acupuncture point for the disease, and further explore its acupuncture point grouping to provide the medical practitioner with the optimal solution for treating the disease and improv</span></span></span><span style="font-family:Verdana;">ing</span><span style="font-family:""><span style="font-family:Verdana;"> the clinical decision-making ability. The Bert-Chinese-Acupoint model was constructed by retraining </span><span style="font-family:Verdana;">on the basis of</span><span style="font-family:Verdana;"> the Bert model, and the semantic features in terms of acupuncture points were added to the acupunctu</span></span><span style="font-family:""><span style="font-family:Verdana;">re point corpus in the fine-tuning process to increase the semantic features in terms of acupuncture </span><span style="font-family:Verdana;">points,</span><span style="font-family:Verdana;"> and compared with the machine learning method. The results show that the Bert-Chinese Acupoint model proposed in this paper has a 3% improvement in accuracy compared to the </span><span style="font-family:Verdana;">best performing</span><span style="font-family:Verdana;"> model in the machine learning approach. 展开更多
关键词 Bert model Machine Learning Classification model comparison
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Applicability of Waterside Corrosion Models in Range of IFPE Database
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作者 Jun Wang Tong Liu Yuemin Zhou 《Journal of Energy and Power Engineering》 2014年第2期318-325,共8页
Fuel rod cladding waterside corrosion is one of the phenomena that limit the life time of nuclear fuel. Corrosion performance depends on the cladding material properties as well as operating conditions during the irra... Fuel rod cladding waterside corrosion is one of the phenomena that limit the life time of nuclear fuel. Corrosion performance depends on the cladding material properties as well as operating conditions during the irradiation of the fuel. As a function of temperature, power history, water chemistry, time, etc., waterside corrosion is of great concern in fuel performance evaluation, especially for high burnup fuels. This paper is dedicated to the study of the waterside corrosion phenomenon using the IFPE database by COPERNIC, which is developed for the analysis of fuel rod behaviors in normal operation and transient conditions. Different models, MATPRO, FRAMATOME and EPRI models, for example, are adopted in the simulations. The results derived from the models are compared and the unconformities are analyzed. Based on the comparative analysis, reasonable models are chosen to simulate certain irradiated fuel rods. Our analyses indicate that potential affecting factors which are not considered in COPERNIC code, such as water chemistry and alloy composition, should be responsible for discrepancies of certain rod predictions. 展开更多
关键词 Waterside corrosion model comparison influencing factors IFPE database.
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Numerical model for homogeneous cohesive dam breaching due to overtopping failure 被引量:5
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作者 ZHONG Qi-ming CHEN Sheng-shui DENG Zhao 《Journal of Mountain Science》 SCIE CSCD 2017年第3期571-580,共10页
Based on the large-scale model tests, a simplified dam breach model for homogeneous cohesive dam due to overtopping failure is put forward. The model considers headcut erosion as one of the key homogeneous cohesive da... Based on the large-scale model tests, a simplified dam breach model for homogeneous cohesive dam due to overtopping failure is put forward. The model considers headcut erosion as one of the key homogeneous cohesive dam breaching mechanisms and we calculate the time-averaged headcut migration rate using an energy-based empirical formula. A numerical method is adopted to determine the initial scour position at the downstream slope in terms of the water head and dam height, and the broad-crested weir equation is utilized to simulate the breach flow. The limit equilibrium method is used to analyze the stability of breach slope during the breach process. An iterative method is developed to simulate the coupling process of soil and water at each time step. The calculated results of three dam breach cases testify the reasonability of the model, and the sensitivity studies of soil erodibility show that sensitivity is dependent on each test case's soil conditions. In addition, three typical dam breach models, NWS BREACH, WinDAM B, and HR BREACH, are also chosen to compare with the proposed model. It is found that NWS BREACH may have large errors for cohesive dams, since it uses a noncohesive sediment transport model and does notconsider headcut erosion, WinDAM B and HR BREACH consider headcut erosion as the breaching mechanism and handle well homogeneous cohesive dam overtopping failure, but overall, the proposed model has the best performance. 展开更多
关键词 KeHomogeneous cohesive dam OVERTOPPING Headcut Initial scour position Sensitivity analysis models comparison
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