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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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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 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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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 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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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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A comparative study of seismic tomography models of Southwest China
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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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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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FGOALS高分辨率气候模式系统模式研制与应用综述
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作者 俞永强 安博 +7 位作者 刘海龙 包庆 林鹏飞 何编 郑伟鹏 栾贻花 白文蓉 李恬燕 《大气科学》 CSCD 北大核心 2024年第1期200-217,共18页
当今气候系统模式发展的重要趋势之一,是通过提高模式的空间分辨率,改进对气候系统中多尺度相互作用过程和极端事件的模拟能力。过去5年里,中国科学院大气物理研究所发展并完善了25 km分辨率大气环流分量模式FAMIL2.2、1/10°分辨... 当今气候系统模式发展的重要趋势之一,是通过提高模式的空间分辨率,改进对气候系统中多尺度相互作用过程和极端事件的模拟能力。过去5年里,中国科学院大气物理研究所发展并完善了25 km分辨率大气环流分量模式FAMIL2.2、1/10°分辨率海洋环流分量模式LICOM3.0,并以此为基础建立了高分辨率气候系统模式FGOALS-f3-H。利用上述高分辨率模式,开展了大量的数值模拟试验和预报/预测研究,其中包括国际耦合模式比较计划第六阶段(CMIP6)的高分辨率模式比较子计划(HighResMIP),建立了海洋环流预测系统(LFS)等。初步评估分析表明,相对于低分辨率模式,高分辨率模式对气候平均态和气候变率的模拟能力均有明显改进。其中高分辨率大气环流模式可以更好地模拟台风、极端降水事件,高分辨率海洋模式可以更好地模拟海洋中尺度涡旋和西边界流,而高分辨率耦合模式则可以更好重现中尺度海气相互作用过程、热带不稳定波动(TIW)等事件。 展开更多
关键词 气候系统模式 高分辨率 多尺度相互作用 国际耦合模式比较计划(CMIP)
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国外高校社会创新创业教育的模式比较和经验启示
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作者 钟晓华 孙湘茗 《创新与创业教育》 2024年第2期163-170,共8页
在不确定性增加的背景下,社会创新创业的重要性日益凸显。高校作为创新人才培养的前沿阵地,纷纷将社会创新创业教育融入专业教育、双创教育及职业教育。在梳理社会创新创业教育的相关概念、分析其在国外高校的发展趋势的基础上,对比分... 在不确定性增加的背景下,社会创新创业的重要性日益凸显。高校作为创新人才培养的前沿阵地,纷纷将社会创新创业教育融入专业教育、双创教育及职业教育。在梳理社会创新创业教育的相关概念、分析其在国外高校的发展趋势的基础上,对比分析了英、美、日、韩高校专业融入型、通识平台型、新增专业型、创业项目型四种社会创新创业教育模式及其差异化使用情境,以及在课程体系改进、实践平台建构、育人队伍培育等方面对我国创新创业教育的启示。 展开更多
关键词 社会创新创业 高等教育 模式比较
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基于缩尺模型的高铁桥梁预应力损失试验研究
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作者 许开成 黄凌娟 +3 位作者 李鹏清 张立卿 邱日旭 陈梦成 《华东交通大学学报》 2024年第2期48-55,共8页
【目的】为更好的评估在役预应力混凝土桥梁结构预应力损失状况。【方法】选用国内高铁中应用最广的32 m预应力混凝土箱梁作为研究对象,按照1:16的缩尺比例将箱梁转化为T形截面制作了26根C50混凝土试验模型梁。通过对试验梁预应力钢绞... 【目的】为更好的评估在役预应力混凝土桥梁结构预应力损失状况。【方法】选用国内高铁中应用最广的32 m预应力混凝土箱梁作为研究对象,按照1:16的缩尺比例将箱梁转化为T形截面制作了26根C50混凝土试验模型梁。通过对试验梁预应力钢绞线应变、伸长量的瞬时和长期监测得到预应力损失的实际值,并将此实际值与目前国内外常用预应力损失规范计算所得值进行对比分析。【结果】预应力损失主要发生在前期即瞬时损失,约占总损失的70%;84.6%的试验梁锚固损失占瞬时损失总和的70%以上,最高达80.57%;试验梁的长期损失在锚固后的前10 d内变化较快,后期逐渐趋于稳定;将5种规范的计算结果与试验实测值进行对比,对于长期损失,数据显示实测数据与《铁路桥涵设计规范》(TB 10002—2017)计算结果最为吻合。【结论】研究结果可为实际工程中预应力梁的预应力损失计算提供参考。 展开更多
关键词 预应力混凝土梁 预应力损失 缩尺模型 规范对比 应变监测
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艺术介入乡村建设的设计竞赛与实践模式
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作者 张军 戴梦雅 +1 位作者 周子涵 梁可 《设计》 2024年第11期32-35,共4页
研究艺术介入乡村建设的设计竞赛与实践案例,探究两者价值差异与融合路径,为我国乡村建设提供经验启示。多途径收集高价值竞赛与实践案例,依据社区营造切入点,从人、文、景、地、产五方面进行分类,筛选出典型案例进行深入解构,从切入点... 研究艺术介入乡村建设的设计竞赛与实践案例,探究两者价值差异与融合路径,为我国乡村建设提供经验启示。多途径收集高价值竞赛与实践案例,依据社区营造切入点,从人、文、景、地、产五方面进行分类,筛选出典型案例进行深入解构,从切入点、设计手段、资源整合等层面纵向分析设计竞赛与实践案例的路径特点,横向对比二者的异同优劣。归纳得出实践与竞赛纵向的显著规律,在两者横向对比中提炼之间差异、联系及转化融合的可能方式。对现有艺术乡建设计竞赛与实践案例的分析反思,有利于探索两者未来的融合发展方向。 展开更多
关键词 艺术介入 乡村建设 设计竞赛 实践模式 案例比较
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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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无人机航测方案设计及数据处理研究
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作者 郎博 杨任旭 邱亚辉 《北京工业职业技术学院学报》 2024年第3期32-35,共4页
近几年,无人机航空摄影测量技术发展迅速,以无人机为平台进行低空摄影测量成为众多测绘人员开展相关工作的一个新选择。以无人机为平台,搭载高分辨率相机,对无人机航测方案进行设计及内业数据处理,生成数字高程模型(DEM)与数字正射影像(... 近几年,无人机航空摄影测量技术发展迅速,以无人机为平台进行低空摄影测量成为众多测绘人员开展相关工作的一个新选择。以无人机为平台,搭载高分辨率相机,对无人机航测方案进行设计及内业数据处理,生成数字高程模型(DEM)与数字正射影像(DOM)等数字模型,并对比分析了PhotoScan和Pix4D两种软件生成DOM的质量与精度。通过对无人机航测方案的设计及数字模型成果的对比研究,为绘制大比例尺地形图等航测作业提供了参考。 展开更多
关键词 无人机 航测方案设计 数字模型 精度分析与对比
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水平受荷桩“p-y+M-θ”分析方法
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作者 王立忠 赖踊卿 +1 位作者 洪义 张友虎 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第5期905-918,共14页
中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变... 中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变形和承载能力,过于保守的设计给海上风电降本带来挑战。为此建立了能以统一的方式预测柔性、刚柔性和刚性单桩水平单调受荷响应的“p-y+M-θ”模型,并将该模型推广到循环荷载下单桩的响应分析。通过与相关试验结果比对发现,“p-y+M-θ”模型能较为准确地预测桩基水平加载响应。力图为水平受荷单桩工程设计提供简洁而可行的响应分析方法。 展开更多
关键词 软黏土 “p-y+M-θ”模型 水平受荷桩循环加载 试验结果对比
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我国医疗保险国谈药品单独支付政策省际比较研究 被引量:2
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作者 杨钰婷 胡婉慈 左根永 《中国卫生政策研究》 CSCD 北大核心 2024年第1期24-29,共6页
目的:对国家医疗保险谈判药品单独支付省级政策文本进行分析,总结关键措施及特点,为各省制定和优化单独支付政策提供借鉴。方法:检索各省、自治区、直辖市医疗保障局网站,收集有关单独支付的政策文件,对检索到的政策文本进行总结与分析... 目的:对国家医疗保险谈判药品单独支付省级政策文本进行分析,总结关键措施及特点,为各省制定和优化单独支付政策提供借鉴。方法:检索各省、自治区、直辖市医疗保障局网站,收集有关单独支付的政策文件,对检索到的政策文本进行总结与分析。结果:各省份单独支付政策在目录发布、目录遴选方式、药品管理方式、政策待遇水平和政策衔接等方面存在差异。结论:单独支付政策是“三医”协同发展的重要推手。各省要平衡好单独支付目录各种政策要素,处理好医保基金控制和患者获得感以及理清单独支付政策与支持创新药发展的关系,减少“三医”协同障碍。 展开更多
关键词 国谈药品 单独支付政策 管理模式 政策比较
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不同模型对MMC-HVDC系统大信号稳定性分析准确性影响的对比研究
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作者 阚鹏 郑华俊 +4 位作者 袁旭峰 熊炜 魏威 张元慧 蔡永翔 《智慧电力》 北大核心 2024年第5期105-113,共9页
模块化多电平换流器高压直流输电(MMC-HVDC)系统运行中不可避免地遭受大信号扰动,可能导致不稳定现象的发生。基于混合势理论(MPT)对比分析了MMC-HVDC系统3种不同模型下的大信号稳定性。首先,建立了MMC-HVDC系统的全阶模型、降阶模型和... 模块化多电平换流器高压直流输电(MMC-HVDC)系统运行中不可避免地遭受大信号扰动,可能导致不稳定现象的发生。基于混合势理论(MPT)对比分析了MMC-HVDC系统3种不同模型下的大信号稳定性。首先,建立了MMC-HVDC系统的全阶模型、降阶模型和等效恒功率负载(CPL)模型,并从理论层面对比分析了三者之间的差异性。利用MPT分别推导了基于3种模型的MMC-HVDC系统大信号稳定性判据,对比研究了3种不同模型对大信号稳定性分析结果的影响,并做出了系统在电网电压暂降大扰动下的稳定运行边界。最后,通过Matlab/Simulink时域仿真验证了理论分析的正确性。 展开更多
关键词 柔性直流输电 大信号稳定性 模型准确性对比 混合势理论
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