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Research on Optimization of Audit Risk Relationship Model Based on Responsibility Subject
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作者 WANG Shufeng LI Xianglin 《Journal of Modern Accounting and Auditing》 2025年第4期281-286,共6页
Based on the objective reality that audit risk responsibility has mainly been attributed to certified public accountants in the past,and audit standards have not specifically divided the entities responsible for audit... Based on the objective reality that audit risk responsibility has mainly been attributed to certified public accountants in the past,and audit standards have not specifically divided the entities responsible for audit risk responsibility,combined with the understanding of the types of audit risk elements related to audit standards,the differences in the understanding of audit risk and its relationship model application caused by the different audit cultures in China and the West have led to a bias of Chinese certified public accountants to bear inspection risks,which affects their professional enthusiasm and continues to cause accounting firms to be lazy in audit quality management.Based on this,literature research,case analysis,and logical deduction methods were used to redefine the concept of audit risk from the perspective of risk responsibility subjects.The traditional audit risk elements and their relationship models were briefly introduced,and the identification of audit risk elements and optimization of audit risk relationship models were systematically demonstrated. 展开更多
关键词 responsible party audit risk relationship model contract risk report risk
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Mechanical Properties and Stress Strain Relationship Models for Bamboo Scrimber 被引量:22
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作者 Haitao Li Huizhong Zhang +6 位作者 Zhenyu Qiu Jingwen Su Dongdong Wei Rodolfo Lorenzo Conggan Yuan Hongzheng Liu Chungui Zhou 《Journal of Renewable Materials》 SCIE EI 2020年第1期13-27,共15页
In order to investigate the basic mechanical properties and stress strain relationship model for bamboo scrimber manufactured based on a new technique,a large quantities of experiments have been carried out.Based on t... In order to investigate the basic mechanical properties and stress strain relationship model for bamboo scrimber manufactured based on a new technique,a large quantities of experiments have been carried out.Based on the analysis of the test results,the following conclusions can be drawn.Two main typical failure modes were classified for bamboo scrimber specimens both under tension parallel to grain and tension perpendicular to grain.Brittle failure happened for all tensile tests.The slope values for the elastic stages have bigger discreteness compared with those for the specimens under tensile parallel to grain.The failure modes for bamboo scrimber specimens under compression parallel to grain could be divided into four.Only one main failure mode happened both for the bending specimens and the shear specimens.With the COV values of 28.64 and 25.72 respectively,the values for the strength and elastic modulus under tensile perpendicular to grain have the largest discreteness for bamboo scrimber.From the point of CHV values,the relationship among the mechanical parameters for bamboo scrimber were proposed based on the test results.Compared with other green building materials,bamboo scrimber manufactured based on a new technique has better mechanical performance and could be used in construction area.Three stress strain relationship models which are four-linear model,quadratic function model,and cubic function model were proposed for bamboo scrimber specimens manufactured based on a new technique.The latter two models gives better prediction for stress strain relationship in elastic plastic stage. 展开更多
关键词 Bamboo scrimber parallel to grain perpendicular to grain stress-strain relationship model
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Precipitation-Surface Temperature Relationship in the IPCC CMIP5 Models 被引量:7
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作者 吴仁广 陈洁鹏 温之平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期766-778,共13页
Precipitation and surface temperature are two important quantities whose variations are closely related through various physical processes. In the present study, we evaluated the precipitation-surface temperature (P-... Precipitation and surface temperature are two important quantities whose variations are closely related through various physical processes. In the present study, we evaluated the precipitation-surface temperature (P-T) relationship in 17 climate models involved in the Coupled Model Intercomparison Project Phase 5 (CMIP5) for the IPCC Assessment Report version 5. Most models performed reasonably well at simulat- ing the large-scale features of the P-T correlation distribution. Based on the pattern correlation of the P-T correlation distribution, the models performed better in November-December-January-February-March (NDJFM) than in May-June-July-August-September (MJJAS) except for the mid-latitudes of the North- ern Hemisphere, and the performance was generally better over the land than over the ocean. Seasonal dependence was more obvious over the land than over the ocean and was more obvious over the mid- and high-latitudes than over the tropics. All of the models appear to have had difficulty capturing the P-T correlation distribution over the mid-latitudes of the Southern Hemisphere in MJJAS. The spatial variabil- ity of the P-T correlation in the models was overestimated compared to observations. This overestimation tended to be larger over the land than over the ocean and larger over the mid- and high-latitudes than over the tropics. Based on analyses of selected model ensemble simulations, the spread of the P-T correlation among the ensemble members appears to have been small. While the performance in the P-T correlation provides a general direction for future improvement of climate models, the specific reasons for the discrep- ancies between models and observations remain to be revealed with detailed and comprehensive evaluations in various aspects. 展开更多
关键词 precipitation-surface temperature relationship CMIP5 models seasonal dependence
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Modeling of the height–diameter relationship using an allometric equation model:a case study of stands of Phyllostachys edulis 被引量:1
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作者 Xuan Gao Zhandong Li +5 位作者 Hongmei Yu Zehui Jiang Chen Wang Yu Zhang Lianghua Qi Lei Shi 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期339-347,共9页
Understanding the relationship between tree height (H) and diameter at breast height (D) is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its appli... Understanding the relationship between tree height (H) and diameter at breast height (D) is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its applicability for unevenly aged stands of moso bamboo forest at a regional scale. Field data were collected for 21 plots. Based on these data, we identified two strong power relationships: a corre- lation between the mean bamboo height (Hm) and the upper mean H (Hu), and a correlation between the mean D (Din) and the upper mean D (Du). Simulation results derived from the aUometric equation model were in good agreement with observed culms derived from the field data for the 21 stands, with a root-mean-square error and relative root-mean-square error of 1.40 m and 13.41%, respectively. These results demonstrate that the allometric equation model had a strong predictive power in the unevenly aged stands at a regional scale. In addition, the estimated average height-diameter (H-D) model for South Anhui Province was used to predict H for the same type of bamboo in Hunan Province based on the measured D, and the results were highly similar. The allometric equation model has multiple uses at the regional scale, including the evaluation of the variation in the H- D relationship among regions. The model describes the average H-D relationship without considering the effects caused by variation in site conditions, tree density and other factors. 展开更多
关键词 Allometric equation Bamboo Height-diameter relationship model Phyllostachys edulis POACEAE STRATIFICATION
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Machine Learning-Based Quantitative Structure-Activity Relationship and ADMET Prediction Models for ERα Activity of Anti-Breast Cancer Drug Candidates 被引量:7
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作者 XU Zonghuang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第3期257-270,共14页
Breast cancer is presently one of the most common malignancies worldwide,with a higher fatality rate.In this study,a quantitative structure-activity relationship(QSAR)model of compound biological activity and ADMET(Ab... Breast cancer is presently one of the most common malignancies worldwide,with a higher fatality rate.In this study,a quantitative structure-activity relationship(QSAR)model of compound biological activity and ADMET(Absorption,Distribution,Metabolism,Excretion,Toxicity)properties prediction model were performed using estrogen receptor alpha(ERα)antagonist information collected from compound samples.We first utilized grey relation analysis(GRA)in conjunction with the random forest(RF)algorithm to identify the top 20 molecular descriptor variables that have the greatest influence on biological activity,and then we used Spearman correlation analysis to identify 16 independent variables.Second,a QSAR model of the compound were developed based on BP neural network(BPNN),genetic algorithm optimized BP neural network(GA-BPNN),and support vector regression(SVR).The BPNN,the SVR,and the logistic regression(LR)models were then used to identify and predict the ADMET properties of substances,with the prediction impacts of each model compared and assessed.The results reveal that a SVR model was used in QSAR quantitative prediction,and in the classification prediction of ADMET properties:the SVR model predicts the Caco-2 and hERG(human Ether-a-go-go Related Gene)properties,the LR model predicts the cytochrome P450 enzyme 3A4 subtype(CYP3A4)and Micronucleus(MN)properties,and the BPNN model predicts the Human Oral Bioavailability(HOB)properties.Finally,information entropy theory is used to validate the rationality of variable screening,and sensitivity analysis of the model demonstrates that the constructed model has high accuracy and stability,which can be used as a reference for screening probable active compounds and drug discovery. 展开更多
关键词 anti-breast cancer drug discovery quantitative structure-activity relationship(QSAR)model ADMET(Absorption Distribution Metabolism Excretion Toxicity)prediction machine learning
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Numerical Method for Modeling the Constitutive Relationship of Sand under Different Stress Paths 被引量:5
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作者 Ren Qingyang Wang Jingtao 《Journal of China University of Geosciences》 SCIE CSCD 2005年第3期268-270,共3页
A numerical method was used in order to establish the constitutive relationship of sands under different stress paths, Firstly, based on the numerical method modeling the constitutive law of sands, the elastoplastic c... A numerical method was used in order to establish the constitutive relationship of sands under different stress paths, Firstly, based on the numerical method modeling the constitutive law of sands, the elastoplastic constitutive relationship of sand was established for three paths: the constant proportion of principle stress path, the conventional triaxial compression (CTC) path, and the p=constant (TC) path. The yield lines of plastic volumetric strain and plastic generalized shear strain were given. Through visualization, the three dimensional surface of the stress-strain relationship in the whole stress field (p, q) obtained under the three paths was plotted. Also, by comparing the stress-strain surfaces and yield locus of the three stress paths, the differences were found to be obvious, which demonstrates that the influence of the stress paths on constitutive law was not neglected. The numerical modeling method overcame the difficulty of finding an analytical expression for plastic potential. The results simulated the experimental data with an accuracy of 90% on average, so the constitutive model established in this paper provides an effective constitutive equation for this kind of engineering, reflecting the effect of practical stress paths that occur in sands. 展开更多
关键词 constitutive relationship numerical method modeling stress path
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Seismic ground motion relationships in southern China based on stochastic finite-fault model
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作者 郑斯华 黄玉龙 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第1期11-21,共11页
The characteristics of seismic ground motions in southern China are difficult to determine statistically due to a lack of strong ground motion data.In this study,a stochastic finite-fault ground motion model was adopt... The characteristics of seismic ground motions in southern China are difficult to determine statistically due to a lack of strong ground motion data.In this study,a stochastic finite-fault ground motion model was adopted to simulate the seismic ground motions at bedrock for southern China,based on parameters derived from small and medium earthquakes that have occurred in the region.From these,the response spectra was estimated.A set of ground motion attenuation relationships was then developed based on simulated peak ground motions and response spectral parameters through regression,which would be applicable for use in engineering practice.Through comparisons,it was demonstrated that the proposed ground motion relationships are generally consistent with those obtained from other reported ground motion attenuation models for southern China. 展开更多
关键词 Stochastic finite-fault model ground motion relationships southern China
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GIS-Based Urbanization Prediction Model Considering Neighborhood Relationship of the Unit of the “Block” in the Outskirts of Metropolitan Area
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作者 Kayoko Yamamoto 《Journal of Geographic Information System》 2014年第4期330-344,共15页
On the outskirts of the metropolitan areas in Japan, the rapid development of urban areas and the improvement in transportation networks have brought various land use problems in their wake, including urban diffusion ... On the outskirts of the metropolitan areas in Japan, the rapid development of urban areas and the improvement in transportation networks have brought various land use problems in their wake, including urban diffusion and the phenomenon of urban sprawl. There is a strong need for accurate predictions of land-use change and future urbanization, as well as investigation of the appropriateness of present land use controls and the land use controls that will be required in the future. This study took as its object the outskirts of the Keihanshin (Kyoto-Osaka-Kobe) Metropolitan Area, the second largest conurbation in Japan after the Tokyo Metropolitan Area, and used the digital maps and spatial analysis offered by GIS. It aimed to: 1) describe the characteristics of land use controls, land use and urbanization;2) develop an urbanization prediction model that considers the neighboring relationship of neighboring areas on a 100 m mesh unit;3) apply this model to the study area and verify its validity regarding the conditions of present land use;4) compare urbanization prediction results by this model with the present land use controls;and 5) make predictions for future urbanization and propose remedial measures for future land use controls. 展开更多
关键词 URBANIZATION Prediction model NEIGHBORHOOD relationship URBAN Diffusion URBAN SPRAWL Land Use CONTROLS
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Relationship between rock uniaxial compressive strength and digital core drilling parameters and its forecast method 被引量:10
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作者 Hongke Gao Qi Wang +3 位作者 Bei Jiang Peng Zhang Zhenhua Jiang Yue Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第4期605-613,共9页
The rock uniaxial compressive strength(UCS)is the basic parameter for support designs in underground engineering.In particular,the rock UCS should be obtained rapidly for underground engineering with complex geologica... The rock uniaxial compressive strength(UCS)is the basic parameter for support designs in underground engineering.In particular,the rock UCS should be obtained rapidly for underground engineering with complex geological conditions,such as soft rock,fracture areas,and high stress,to adjust the excavation and support plan and ensure construction safety.To solve the problem of obtaining real-time rock UCS at engineering sites,a rock UCS forecast idea is proposed using digital core drilling.The digital core drilling tests and uniaxial compression tests are performed based on the developed rock mass digital drilling system.The results indicate that the drilling parameters are highly responsive to the rock UCS.Based on the cutting and fracture characteristics of the rock digital core drilling,the mechanical analysis of rock cutting provides the digital core drilling strength,and a quantitative relationship model(CDP-UCS model)for the digital core drilling parameters and rock UCS is established.Thus,the digital core drilling-based rock UCS forecast method is proposed to provide a theoretical basis for continuous and quick testing of the surrounding rock UCS. 展开更多
关键词 Digital core drilling Mechanical analysis Rock UCS Quantitative relationship model Forecast method
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An LCOR model for suppressing cascading failure in weighted complex networks 被引量:5
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作者 陈世明 庞少鹏 邹小群 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期626-631,共6页
Based on the relationship between capacity and load, cascading failure on weighted complex networks is investigated, and a load-capacity optimal relationship (LCOR) model is proposed in this paper. Compared with thr... Based on the relationship between capacity and load, cascading failure on weighted complex networks is investigated, and a load-capacity optimal relationship (LCOR) model is proposed in this paper. Compared with three other kinds of load- capacity linear or non-linear relationship models in model networks as well as a number of real-world weighted networks including the railway network, the airports network and the metro network, the LCOR model is shown to have the best robustness against cascading failure with less cost. Furthermore, theoretical analysis and computational method of its cost threshold are provided to validate the effectiveness of the LCOR model. The results show that the LCOR model is effective for designing real-world networks with high robustness and less cost against cascading failure. 展开更多
关键词 cascading failure load-capacity optimal relationship model ROBUSTNESS COST
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一种数字孪生辅助聚类的车辆边缘计算任务卸载方法
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作者 巨涛 马雅玲 +1 位作者 康贺廷 火久元 《哈尔滨工业大学学报》 北大核心 2026年第1期92-105,共14页
为解决车辆边缘计算中因高动态网络拓扑结构、高维动作探索空间以及严格的低时延约束引起的任务卸载不稳定、计算资源不能充分利用、卸载成本高、用户服务质量低的问题,本文提出了一种数字孪生辅助聚类的车辆边缘计算任务卸载方法。首... 为解决车辆边缘计算中因高动态网络拓扑结构、高维动作探索空间以及严格的低时延约束引起的任务卸载不稳定、计算资源不能充分利用、卸载成本高、用户服务质量低的问题,本文提出了一种数字孪生辅助聚类的车辆边缘计算任务卸载方法。首先构建了车辆社交关系模型,以量化车辆间的相互关系,通过引入两个社交信任因子衡量车辆间卸载稳定性,减少因通信链路不稳定而造成的计算资源浪费;而后构建数字孪生车辆边缘计算网络模型,通过数字孪生网络模型与实体车载边缘设备网络之间的双向信息交互,实时监控车辆边缘设备的状态;同时,设计了基于引力模型的聚类算法,辅助车辆聚类以缩小动作探索空间,提高计算任务的卸载效率,降低边缘任务计算成本;最后,在以上优化策略的基础上,设计实现了数字孪生辅助聚类的双延迟深度确定性策略梯度边缘计算任务卸载算法。仿真对比实验表明,与已有的卸载方法相比,所提方法在充分利用计算资源的基础上,能够显著减小任务卸载成本,降低任务执行时延并提高任务卸载成功率,可以实现车辆边缘计算任务的高效稳定卸载,提升用户服务质量。 展开更多
关键词 车辆边缘计算 数字孪生网络 社交关系模型 车辆聚类 深度强化学习 动态任务卸载
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Parameter Fitting of Seismic Intensity Attenuation Model in Xinjiang 被引量:1
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作者 Tan Ming Li Shuai +3 位作者 Sun Jing Wang Wei Tang Lihua Wu Chuanyong 《Earthquake Research in China》 2013年第2期261-268,共8页
By using the existing historical earthquake investigation data in Xinjiang,this paper obtained the envelope curves of isoseismal maps of 103 destructive earthquakes occurring from 1716 to 2010 after digitization of th... By using the existing historical earthquake investigation data in Xinjiang,this paper obtained the envelope curves of isoseismal maps of 103 destructive earthquakes occurring from 1716 to 2010 after digitization of the data. The author summarized the seismic intensity attenuation laws in the Xinjiang region with the multiple regression fitting method. The intensity attenuation function of the elliptical model was provided and the fitting results in different periods and areas were compared. Finally, the intensity attenuation relationship in the Xinjiang region was obtained by the method of constraining the start and end of the attenuation curves. 展开更多
关键词 Seismic intensity Attenuation relationship model Xinjiang
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基于联邦图神经网络的网络威胁情报安全共享研究
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作者 樊一凡 《情报杂志》 北大核心 2026年第2期57-64,共8页
提升网络威胁情报共享的安全性和隐私性,对于加强安全情报体系建设、加快情报资源深度释放、加速威胁态势情报感知具有重要积极意义。针对网络威胁情报共享过程中的安全性保障不足、特征提取深度有限、共享方案与结构特性不匹配问题,提... 提升网络威胁情报共享的安全性和隐私性,对于加强安全情报体系建设、加快情报资源深度释放、加速威胁态势情报感知具有重要积极意义。针对网络威胁情报共享过程中的安全性保障不足、特征提取深度有限、共享方案与结构特性不匹配问题,提出一种基于联邦图神经网络的网络威胁情报安全共享模型(CTISS-FG)。首先,建模网络威胁情报共享的整体架构;其次,以图神经网络(GNN)建模网络威胁情报实体关系网络并提取蕴含在复杂拓扑结构特征,结合联邦学习(FL)框架和全同态加密(FHE)技术,保障共享阶段的隐私性和安全性;最后,结合实际威胁情报数据并设计置信度阈值实现情报共享。CTISS-FG模型在精确率、F1值等指标上领先其他基线模型,在DNRTI数据集上的精确率、召回率、F1值分别达到0.854、0.844、0.849,该模型对于打破信息孤岛、促进情报交互、解锁高敏情报具备一定的实践价值。 展开更多
关键词 联邦图神经网络 网络威胁情报 情报共享 实体关系 CTISS-FG模型
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A Comparative Study of the Jerome Model and the Horace Model 被引量:1
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作者 黄淋 唐学琳 《科技信息》 2012年第6期179-180,共2页
This paper will try to compare the Jerome model with the Horace model to look into advantages, shortages and relationship be-tween them. It mainly discusses the important roles of the Jerome model and the Horace model... This paper will try to compare the Jerome model with the Horace model to look into advantages, shortages and relationship be-tween them. It mainly discusses the important roles of the Jerome model and the Horace model in turning Chinese from their translation ef-fects. The present article comes to a conclusion that they are opposite, related, complementary, melting and permeating. And it gives us anidea that we should neither praise nor censure either of them, and we should adopt a correct method according to the concrete conditions toachieve a perfect translation effect. 展开更多
关键词 英语教学 教学方法 阅读教学 阅读知识
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多理论整合视角下的子宫内膜癌患者整体护理方案构建与实践
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作者 魏东 《首都食品与医药》 2026年第1期111-114,共4页
子宫内膜癌是女性生殖系统常见的恶性肿瘤之一,其发病率呈逐年上升趋势。术后患者常面临疼痛、淋巴水肿、血栓及焦虑抑郁等多重困扰,严重影响康复进程与生活质量。现有护理多聚焦于单一症状或短期干预,缺乏系统化、连续性的整体方案。... 子宫内膜癌是女性生殖系统常见的恶性肿瘤之一,其发病率呈逐年上升趋势。术后患者常面临疼痛、淋巴水肿、血栓及焦虑抑郁等多重困扰,严重影响康复进程与生活质量。现有护理多聚焦于单一症状或短期干预,缺乏系统化、连续性的整体方案。近年来,许多学者研究探索了多种护理方法,如基于岗位管理的护理干预、气压治疗仪联合5E康复管理理论指导下的整体护理、饮食护理等。结果显示,整体护理方案能改善患者的治疗效果和生活质量,增强自理能力和社会适应能力。基于此,本研究通过整合奥瑞姆自理理论、罗伊适应模式及佩皮劳人际关系模式理论,结合子宫内膜癌患者的实际需求,设计出一套多维度护理措施,旨在提高患者的治疗效果和生活质量,为临床治疗提供借鉴。 展开更多
关键词 多理论整合 子宫内膜癌 整体护理 护理方案 奥瑞姆自理理论 罗伊适应模式 佩皮劳人际关系模式
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Hormesis has emerged as a more common and fundamental dose-response model than the threshold or linear-no-threshold(LNT) models 被引量:6
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作者 Edward J. Calabrese Lu Rong-zhu 《毒理学杂志》 CAS CSCD 北大核心 2006年第2期117-118,共2页
在回顾传统的有阈和线性无阈的剂量-反应关系的基础上,分析此类该模型被毒理学领域认同的主要原因和其在预测低剂量效应中的缺陷,进而提出了高剂量接触呈现抑制效应,而低剂量却呈现促进或刺激作用这一全面的激效兴奋性剂量-反应关系,弥... 在回顾传统的有阈和线性无阈的剂量-反应关系的基础上,分析此类该模型被毒理学领域认同的主要原因和其在预测低剂量效应中的缺陷,进而提出了高剂量接触呈现抑制效应,而低剂量却呈现促进或刺激作用这一全面的激效兴奋性剂量-反应关系,弥补了现有模型的不足,并充分论证这种激效性剂量-反应关系在不同种属、接触因素和生物学终点中的普遍性,并探讨了不同物质的激效兴奋作用的可能机制以及激效兴奋模型的三大优点,最后提出了激效模型谋求广泛接受的现实困难和发展趋势。 展开更多
关键词 激效作用 兴奋效应 剂量-反应关系 有阈模型 线性无阈模型
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The Criticism and Amendment for the Dual-Factor Model of Mental Health: From Chinese Psychological Suzhi Research Perspectives 被引量:5
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作者 Xinqiang Wang Dajun Zhang 《International Journal of Clinical Medicine》 2012年第5期319-327,共9页
Aiming at the limitations of psychopathology (PTH), the dual-factor model of mental health (DFM) was proposed as a new mental health concept and methodology under the background of positive psychology trend. In this p... Aiming at the limitations of psychopathology (PTH), the dual-factor model of mental health (DFM) was proposed as a new mental health concept and methodology under the background of positive psychology trend. In this paper we propose giving an overview of DFM, and doubt, criticize, and modify DFM from the perspective of Chinese psychological suzhi research. The available literature from 1983 to 2012 that is related to DFM and concerning psychological suzhi research in the past 20 years has been reviewed. In addition, we also absorbed the idea of positive psychology and Traditional Chinese Medicine (TCM) Constitution theory to develop theoretically the relationship model between psychological suzhi and mental health. The relationship model between psychological suzhi and mental health modifies and transcends PTH and DFM. It will be the new research area of mental health research. 展开更多
关键词 Dual-Factor model of MENTAL HEALTH PSYCHOPATHOLOGY relationship model between PSYCHOLOGICAL Suzhi and MENTAL HEALTH Subjective Well-Being
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Local and generalized height-diameter models with random parameters for mixed,uneven-aged forests in Northwestern Durango,Mexico 被引量:5
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作者 Sacramento Corral-Rivas Juan Gabriel lvarez-González +1 位作者 Felipe Crecente-Campo José Javier Corral-Rivas 《Forestry Studies in China》 CAS 2014年第1期41-49,共9页
Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variabl... Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variables as predictors.Methods:The data were obtained from 44 permanent plots used to monitor stand growth under forest management in the study area.Results:The generalized Bertalanffy-Richards model performed better than the other generalized models in predicting the total height of the species under study.For the genera Pinus and Quercus,the models were successfully calibrated by measuring the height of a subsample of three randomly selected trees close to the mean d,whereas for species of the genera Cupressus,Arbutus and Alnus,three trees were also selected,but they are specifically the maximum,minimum and mean d trees.Conclusions:The presented equations represent a new tool for the evaluation and management of natural forest in the region. 展开更多
关键词 Conifer and broadleaves forests h-d relationship Mixed models Calibration
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A prediction model for horizontal run-out distance of landslides triggered by Wenchuan earthquake 被引量:6
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作者 Yang Changwei Zhang Jianjing Zhang Ming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期201-208,共8页
The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a lands... The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a landslide L. Correlations among them are studied statistically based on field investigations from 67 landslides triggered by the ground shaking and other factors during the Wenchuan earthquake, and then a prediction model for horizontal run-out distance L is developed in this study. This model gives due consideration to the implications of the above four parameters on the horizontal run-out distance L and the validity of the model is verified by the Donghekou and Magong Woqian landslides. At the same time, the advantages of the model are shown by comparing it with two other common prediction methods. The major findings drawn from the analyses and comparisons are: (1) an exponential relationship exists between L and log V, L and log HL, L and log PGA separately, but a negative exponential relationship exists between L and log tan0, which agrees with the statistical results; and (2) according to the analysis results of the relative relationship between the height of a mountain (H) and the place where the landslides occur, the probabilities at distances of2H/3-H, H/3-2H/3, and O-H/3 are 70.8%, 15.4%, and 13.8%, respectively, revealing that most landslides occurred at a distance of H/2-H. This prediction model can provide an effective technical support for the prevention and mitigation of landslide hazards. 展开更多
关键词 Wenchuan earthquake LANDSLIDES run-out distance prediction model relationship
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Proposal and evaluation of a new norm index-based QSAR model to predict pEC50 and pCC50 activities of HEPT derivatives 被引量:2
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作者 Kanwal Shahid Qiang Wang +4 位作者 Qingzhu Jia Lei Li Xue Cui Shuqian Xia Peisheng Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第10期1464-1469,共6页
The search and development of anti-HIV drugs is currently one of the most urgent tasks of pharmacological studies. In this work, a quantitative structure-activity relationship (QSAR) model based on some new norm ind... The search and development of anti-HIV drugs is currently one of the most urgent tasks of pharmacological studies. In this work, a quantitative structure-activity relationship (QSAR) model based on some new norm indexes, was obtained to a series of more than 150 HEPT derivatives (1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine) to find their pEC50 (the required effective concentration to achieve 50% protection of MT-4 cells against the cytopathic effect of virus) and pCC50 (the required cytotoxic concentration to reduce visibility of 50% mock infected cell) activities. The model efficiencies were then validated using the leave-one-out cross validation (LOO-CV) and y- randomization test. Results indicated that this new model was efficient and could provide satisfactory results for prediction of pECso and pCC50 with the higher R2 train and the higher Rt2est. By using the leverage approach, the applicability domain of this model was further investigated and no response outlier was detected for HEFT derivatives involved in this work. Comparison results with reference methods demonstrated that this new method could result in significant improvements for predicting pEC50 and pCC50 of anti-HIV HEPT derivatives. Moreover, results shown in this present study suggested that these two absolutely different activities pECso and pCC50 of anti-HIV HEPT derivatives could be predicted well with a totally similar QSAR model, which indicated that this model mizht have the potential to be further utilized for other biological activities of HEFT derivatives. 展开更多
关键词 Mathematical modeling Structure-activity relationship Pharmaceuticals HEFT derivatives Anti-HIV-1 activity Prediction
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