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ORDINATION AND GRADIENT ANALYSIS OF CONIFEROUS FOREST IN DAXINGANLING
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作者 Yang Guoting Chen XiangweiNortheast Forestry UniversityZhou DanBotanical Garden of Heilongjiang Province 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1992年第1期42-47,共6页
In this paper,the quantitative approach is applied on the study of coniferous forestbased on the data which were collected by the field investigation in Daxinganling region.The mainpurpose is objectively to show the p... In this paper,the quantitative approach is applied on the study of coniferous forestbased on the data which were collected by the field investigation in Daxinganling region.The mainpurpose is objectively to show the position of communities in the space and the relationship be-tween the community and environment.By means of ordination,it is found that dahurian larch for-est,mongolian scots pine forest and korean fir forest lie in different positions. Gradient analysis ofthree dominant types of conigerous forest has revealed the difference of ecological amplitude,thedifference is one of the important reasons that determine the different communities in the differentenvironment. 展开更多
关键词 ordination GRADIENT ANALYSIS CONIFEROUS FOREST
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Feasibility of Multi-lateral Co-ordination in the Asia-Pacific
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《Contemporary International Relations》 1992年第11期8-11,共4页
There are really piles of tasks before the Asia-Pacific as the region is approach-ing the 21st century. The course of development of some of the major trendsand contradictions can be foreseen. But the complexity of th... There are really piles of tasks before the Asia-Pacific as the region is approach-ing the 21st century. The course of development of some of the major trendsand contradictions can be foreseen. But the complexity of the situation caused bymulti-laterality and the interdependence and interaction of the countries of the re-gion requires that we should break through the old framework of thinking, 展开更多
关键词 ordination thinking PILES adopt really BUDGET break DIALOGUE sized friendly
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Mapping forest vegetation patterns in an Atlantic-Mediterranean transitional area by integration of ordination and geostatistical techniques
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作者 Adriana E.Olthoff Cristina Gómez +1 位作者 Josu G.Alday Carolina Martínez-Ruiz 《Journal of Plant Ecology》 SCIE CSCD 2018年第1期114-122,共9页
Aims Forest vegetation variability may be explained by the complex inter-play among several spatial structuring factors,including climate and topography.We modelled the spatial variability of forest vegetation assembl... Aims Forest vegetation variability may be explained by the complex inter-play among several spatial structuring factors,including climate and topography.We modelled the spatial variability of forest vegetation assemblages and significant environmental variables along a com-plex environmental gradient or coenocline to produce a detailed cartographic database portraying the distribution of forests along it.Methods We combined an analysis of ordination coenoclines with kriging over 772 field data plots from the third Spanish National Forest Inventory in an Atlantic-Mediterranean transitional area(northern Spain).Important Findings The best fitted empirical semivariogram revealed a strong spatial structure of forest species composition along the complex envi-ronmental gradient considered(the climatic-topographic gradient from north to south).The steady and gradual increase of semivari-ance with a marked lag distance indicates a gradual turnover of forest assemblages according to the climatic-topographic vari-ations(regional or local).Two changes in the slope of the semi-variogram suggest the existence of two different scales of spatial variation.The interpolation map by Kriging of forest vegetation assemblages along the main coenocline shows a clear spatial dis-tribution pattern of trees and shrubs in accordance with the spa-tial variation of significant environmental variables.We concluded that the multivariate geostatistical approach is a suitable technique for spatial analysis of forest systems employing data from national forest inventories based on a regular network of field plots.The development of an assortment of maps describing changes in veg-etation assemblages and variation in environmental variables is expected to be a suitable tool for an integrated forest management and planning. 展开更多
关键词 coenocline KRIGING National Forest Inventory ordination VARIOGRAM
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The Accelerated Expansion of the Universe in the Light of the Maximum Ordinality Principle
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第2期585-602,共18页
The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in pa... The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in parallel” to the tradition-al ones, such as those based, for example, on the hypotheses of “Dark Matter” and “Dark Energy”, or better as a “com-possible” perspective, because it is not understood as being “exclusive”. In fact, it is an approach that, when con-firmed by experimental results, always keeps its validity from an “operative” point of view. This is because, in analogy to the traditional perspectives, on the basis of Popper’s Falsification Principle the corresponding “Generative” Logic on which it is based has not the property of the perfect induction. The basic difference then only consists in the fact that the Evolution of the Universe is now modeled by considering the Universe as a Self-Organizing System, which is thus analyzed in the light of the Maximum Ordinality Principle. 展开更多
关键词 Accelerated Expansion of the Universe Maximum Ordinality Principle Incip-ient Differential Calculus
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The importance of being connected:membrane contact sites and Parkinson’s disease
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作者 Matthew E.Gegg 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第10期2202-2203,共2页
Membrane contact sites (MCS) occur between closely apposed organelles and are a means to transport ions and macromolecules between themselves,co-ordinate cellular metabolism,and direct organelle fission and transport.... Membrane contact sites (MCS) occur between closely apposed organelles and are a means to transport ions and macromolecules between themselves,co-ordinate cellular metabolism,and direct organelle fission and transport.While MCS between the endoplasmic reticulum (ER)and mitochondria has long been investigated。 展开更多
关键词 CONNECTED transport ORDINATE
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A multithreaded parallel upwind sweep algorithm for the S_(N) transport equations discretized with discontinuous finite elements
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作者 Zhi‑Wei Zong Mao‑Song Cheng +1 位作者 Ying‑Chi Yu Zhi‑Min Dai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期229-241,共13页
The complex structure and strong heterogeneity of advanced nuclear reactor systems pose challenges for high-fidelity neutron-shielding calculations. Unstructured meshes exhibit strong geometric adaptability and can ov... The complex structure and strong heterogeneity of advanced nuclear reactor systems pose challenges for high-fidelity neutron-shielding calculations. Unstructured meshes exhibit strong geometric adaptability and can overcome the deficiencies of conventionally structured meshes in complex geometry modeling. A multithreaded parallel upwind sweep algorithm for S_(N) transport was proposed to achieve a more accurate geometric description and improve the computational efficiency. The spatial variables were discretized using the standard discontinuous Galerkin finite-element method. The angular flux transmission between neighboring meshes was handled using an upwind scheme. In addition, a combination of a mesh transport sweep and angular iterations was realized using a multithreaded parallel technique. The algorithm was implemented in the 2D/3D S_(N) transport code ThorSNIPE, and numerical evaluations were conducted using three typical benchmark problems:IAEA, Kobayashi-3i, and VENUS-3. These numerical results indicate that the multithreaded parallel upwind sweep algorithm can achieve high computational efficiency. ThorSNIPE, with a multithreaded parallel upwind sweep algorithm, has good reliability, stability, and high efficiency, making it suitable for complex shielding calculations. 展开更多
关键词 Shielding calculation Discrete ordinates method Discontinuous Galerkin finite element method Unstructured meshes
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An Ordinal Multi-Dimensional Classification(OMDC)for Predictive Maintenance
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作者 Pelin Yildirim Taser 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1499-1516,共18页
Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniq... Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniques have been frequently implemented in this area,the existing studies disregard to the nat-ural order between the target attribute values of the historical sensor data.Thus,these methods cause losing the inherent order of the data that positively affects the prediction performances.To deal with this problem,a novel approach,named Ordinal Multi-dimensional Classification(OMDC),is proposed for estimating the conditions of a hydraulic system's four components by taking into the natural order of class values.To demonstrate the prediction ability of the proposed approach,eleven different multi-dimensional classification algorithms(traditional Binary Relevance(BR),Classifier Chain(CC),Bayesian Classifier Chain(BCC),Monte Carlo Classifier Chain(MCC),Probabilistic Classifier Chain(PCC),Clas-sifier Dependency Network(CDN),Classifier Trellis(CT),Classifier Dependency Trellis(CDT),Label Powerset(LP),Pruned Sets(PS),and Random k-Labelsets(RAKEL))were implemented using the Ordinal Class Classifier(OCC)algorithm.Besides,seven different classification algorithms(Multilayer Perceptron(MLP),Support Vector Machine(SVM),k-Nearest Neighbour(kNN),Decision Tree(C4.5),Bagging,Random Forest(RF),and Adaptive Boosting(AdaBoost))were chosen as base learners for the OCC algorithm.The experimental results present that the proposed OMDC approach using binary relevance multi-dimensional classification methods predicts the conditions of a hydraulic system's multiple components with high accuracy.Also,it is clearly seen from the results that the OMDC models that utilize ensemble-based classification algorithms give more reliable prediction performances with an average Hamming score of 0.853 than the others that use traditional algorithms as base learners. 展开更多
关键词 Machine learning multi-dimensional classification ordinal classification predictive maintenance
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Estimation of surface water content at the Tianwen-1 Zhurong landing site
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作者 Xiang Zhou Yang Liu +2 位作者 Xing Wu ZhenXing Zhao YongLiao Zou 《Earth and Planetary Physics》 EI CSCD 2023年第3期347-355,共9页
China’s first Mars rover,Zhurong,successfully landed in the south of Utopia Planitia.The surface water content at the landing area can provide constraints on mineral formation conditions and help us better understand... China’s first Mars rover,Zhurong,successfully landed in the south of Utopia Planitia.The surface water content at the landing area can provide constraints on mineral formation conditions and help us better understand the evolution of the Martian aqueous and geological environment.In this work,the surface kinetic temperature of the Zhurong landing area was derived by analyzing data from the Mars Express Observatoire pour la Minéralogie,l’Eau,les Glaces et l’Activité(OMEGA)spectrometer.Using the Discrete Ordinate Radiative Transfer(DISORT)model,we performed atmospheric correction and thermal correction for the OMEGA data to obtain the surface effective single-particle absorption thickness(ESPAT)parameter to evaluate the surface water content.The surface water content distribution at the landing area was relatively uniform at a lateral scale of~10 km.At the Zhurong landing site,the surface water content in the topmost layer(a few hundred micrometers)of the regolith was 5−8 weight percent water(wt%H_(2)O),assuming surface particle sizes of<45μm,or 1.6−2.5 wt%H_(2)O,assuming surface particle sizes in the range of 125−250μm.The Mars Surface Composition Detector(MarSCoDe)onboard Zhurong also observed significant H_(2)O/OH signals in the landing area.Our results provide an important regional context for the hydration state of the area and can be further verified by the H content derived from the Laser-Induced Breakdown Spectrometer(LIBS)data of MarSCoDe. 展开更多
关键词 MARS Zhurong surface water content Observatoire pour la Minéralogie l’Eau les Glaces et l’Activité(OMEGA) Discrete Ordinate Radiative Transfer(DISORT)
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Generativity of Self-Organizing Processes and Their Correlative Description in Terms of a Formal Language of Meta-Ordinal Generative Nature, in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第10期3159-3202,共44页
The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be mode... The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be modeled using the Maximum Ordinality Principle and its associated formal language, known as the “Incipient” Differential Calculus (IDC). 展开更多
关键词 Maximum Ordinality Principle Solution to the “Three-Body Problem” Generativity of Self-Organizing Processes Formal Language of Ordinal Generativity Formal Language of Meta-Ordinal Generativity
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新冠疫情背景下大学生职业期望现状及影响因素分析——以天津市某大学为例
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作者 王馨悦 郭燕 刘彩 《产业与科技论坛》 2023年第12期92-95,共4页
目的:了解大学生职业期望现状及影响因素,为专业建设和学生发展提供建议。方法:问卷调查天津某大学大学生683人,描述其职业期望现状,运用卡方检验、ordinal logistic回归模型分析大学生职业期望的影响因素。结果:受疫情影响,项目“提供... 目的:了解大学生职业期望现状及影响因素,为专业建设和学生发展提供建议。方法:问卷调查天津某大学大学生683人,描述其职业期望现状,运用卡方检验、ordinal logistic回归模型分析大学生职业期望的影响因素。结果:受疫情影响,项目“提供五险一金”得分最高,“有出国的机会”得分最低,天津市大学生更倾向于稳定的职业选择;ordinal logistic回归分析得出,是否有参与学生会经历、对职业规划程度、想从事与所就读专业相关的工作程度对职业期望产生影响(P<0.05)。结论:大学生个体应尽早进行职业规划;学校应鼓励学生多参与学生社团组织;学校与社会应提供更多资源和平台,助推学生了解所就读专业对口就业方向,并提供实习实践机会。 展开更多
关键词 大学生 职业期望 卡方检验 ordinal logistic回归
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Three-Drug Therapies in Psychiatry in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”—D.D. 23 Luglio 2023, Tempo Ordinario (3.00 e 10.20)
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第8期2267-2308,共42页
The present paper aims at showing the possible adoption in Psychiatry of a general methodology finalized to prescribe the most appropriate Therapy based on the knowledge of its correlative effects in advance, instead ... The present paper aims at showing the possible adoption in Psychiatry of a general methodology finalized to prescribe the most appropriate Therapy based on the knowledge of its correlative effects in advance, instead of recognizing them ex post. The specific case here considered is the “bipolar disorder”, in which the adoption of three different drugs is the most common practice, although with a possible differentiation between the prescription in the morning and in the evening, respectively. Thus, the proposed methodology will consider the Ordinal Interactions between the various drugs by evaluating their combined effects, which will result as being not a simple additive “sum”, because they are evaluated on the basis of the Maximum Ordinality Principle (MOP) and, in addition, in Adherence to the Explicit Solution to the “Three-Body Problem”. In this way the Methodology here proposed is able to suggest how to account for the synergistic effects of the various drugs, especially when the latter are characterized by different concentrations and, at the same time, by generally different half-lives respectively. 展开更多
关键词 Three-Drug Therapies Bipolar Disorder Psychiatric Therapies Maximum Ordinality Principle (MOP) “Three-Body Problem”
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Solution to the “Three-Body Problem” in the Light of the Maximum Ordinality Principle, as a “Suggestion” for a Ri-Orientation of the Present Scientific Perspective in “Favor” of the “Irreducible Quality”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第1期209-259,共51页
This paper presents the Solution to the “Three-body Problem” in the Light of the Maximum Ordinality Principle. In the first part, however, it starts with the Solution to the Solar System, made up of “11 Bodies”. T... This paper presents the Solution to the “Three-body Problem” in the Light of the Maximum Ordinality Principle. In the first part, however, it starts with the Solution to the Solar System, made up of “11 Bodies”. This is because, in such a context, the “Three-body Problem” can be analyzed in its all descriptive possibilities. Nonetheless, the paper also presents the Solution to the “Three-body Problem” with reference to Systems totally independent from the Solar System, such as, for example, the “Triple Stars” and the “Triple Galaxies”. In this way, the paper offers a sufficiently complete framework concerning the Solution to the “Three-body Problem”, always in the Light of the Maximum Ordinality Principle, described in detail in Appendix A. 展开更多
关键词 Three-Body Problem Light of the Maximum Ordinality Principle Solution to the Solar System
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农民工城市融合路径及影响因素研究——基于三阶段Ordinal Logit模型的实证 被引量:25
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作者 叶俊焘 钱文荣 米松华 《浙江社会科学》 CSSCI 北大核心 2014年第4期86-97,158,共12页
本文依据浙江省农民工城市融合的调查数据,构建三阶段Ordinal Logit模型实证分析了农民工城市融合路径及影响因素。结果表明,农民工城市融合经历经济生存融合、社会交往融合和心理认同三阶段发展路径,经济生存融合由强到弱受职业资格、... 本文依据浙江省农民工城市融合的调查数据,构建三阶段Ordinal Logit模型实证分析了农民工城市融合路径及影响因素。结果表明,农民工城市融合经历经济生存融合、社会交往融合和心理认同三阶段发展路径,经济生存融合由强到弱受职业资格、就业公平、婚姻状况、初始社会资本和居住条件的影响;社会交往融合由强到弱受居住格局、经济生存融合、经济生存状态的未来期许和上网时间的影响;心理认同由强到弱受社会交往融合、长期居留意愿和乡土记忆的影响。整合分析表明,经济生存融合极大制约了农民工城市融合的纵向提升,当前农民工城市融合仍停留在经济生存融合阶段。促进农民工城市融合的政策建议应着重考虑以上因素。 展开更多
关键词 农民工 城市融合 路径 影响因素 ORDINAL LOGIT模型
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基于Ordinal Logistic模型的事故严重性影响因素分析——以翻车事故为例 被引量:15
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作者 胡骥 闫章存 +3 位作者 卢小钊 王鹏 张敏捷 胡万欣 《重庆交通大学学报(自然科学版)》 CAS 北大核心 2018年第4期80-86,共7页
为准确分析影响交通事故严重性的各项因素,引入Ordinal Logistic模型研究驾驶员、车辆、环境因素对事故严重程度的影响,利用统计学方法对模型进行显著性检验。并使用该模型对北卡罗来纳州2010—2014年385个翻车事故样本进行严重性影响... 为准确分析影响交通事故严重性的各项因素,引入Ordinal Logistic模型研究驾驶员、车辆、环境因素对事故严重程度的影响,利用统计学方法对模型进行显著性检验。并使用该模型对北卡罗来纳州2010—2014年385个翻车事故样本进行严重性影响因素分析,所得回归模型符合平行线检验(=0.115 1)和似然比检验(≤0.000 1)。通过模型分析得出变量"安全带"(≤0.000 1)、"路面状况"(=0.013 6)、"道路线形"(=0.005 7)对翻车事故的严重性具有显著影响,研究结果表明:Ordinal Logistic模型适合于分析与揭示影响交通事故严重性的各个因素。 展开更多
关键词 交通运输工程 交通安全 ORDINAL LOGISTIC模型 翻车事故 显著性检验
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基于有序Logit与Probit模型的交通事故严重性影响因素分析 被引量:20
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作者 胡骥 闫章存 +1 位作者 卢小钊 胡万欣 《安全与环境学报》 CAS CSCD 北大核心 2018年第3期836-843,共8页
为准确分析影响交通事故严重性的各项因素,引入有序选择模型中的Ordinal Logit模型和Ordinal Probit模型,研究驾驶员、车辆、环境、管理因素与事故严重程度之间的耦合关系,利用计量经济学理论和统计学方法对模型进行显著性检验。并选择... 为准确分析影响交通事故严重性的各项因素,引入有序选择模型中的Ordinal Logit模型和Ordinal Probit模型,研究驾驶员、车辆、环境、管理因素与事故严重程度之间的耦合关系,利用计量经济学理论和统计学方法对模型进行显著性检验。并选择美国北卡罗来纳州2010年至2014年385个翻车事故样本进行严重性影响因素分析,所得回归模型参数估计均符合Wald检验(p≤0.0001)和似然比检验(p≤0.0001),模型的拟合度也都符合Pearson检验(p=0.7976)、偏差检验(p=0.6006)和信息准则检验,模型预测精度指标值均大于0.7。所得两个模型中变量"安全带"(p≤0.001)、"路面状况"(p=0.0071)、"道路线形"(p=0.0077)、"路面类型"(p=0.0251)都对翻车事故的严重性具有显著影响,表明有序Logit模型和有序Probit模型均适用于分析和揭示影响交通事故严重性的各个因素。 展开更多
关键词 安全工程 交通事故严重程度 翻车事故 ORDINAL LOGIT模型 ORDINAL PROBIT模型
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农村学校撤并对学生上学距离的影响——基于GIS和Ordinal Logit模型的分析 被引量:22
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作者 赵丹 吴宏超 Bruno Parolin 《教育学报》 CSSCI 北大核心 2012年第3期62-73,共12页
农村义务教育学校布局调整是以撤并小规模学校为主要手段,旨在促进教育资源均衡配置的一项重大教育政策。通过广东省某山区县2003—2009年的学校布局规划数据,从物理距离、时间距离和文化距离的分类视角,运用GIS技术和Ordinal Logit模... 农村义务教育学校布局调整是以撤并小规模学校为主要手段,旨在促进教育资源均衡配置的一项重大教育政策。通过广东省某山区县2003—2009年的学校布局规划数据,从物理距离、时间距离和文化距离的分类视角,运用GIS技术和Ordinal Logit模型分析农村学校撤并对学生上学距离产生的直接影响。研究结果表明:撤并农村学校导致学生上学的物理距离和时间距离增加,偏远学生上学难问题凸显;对学生的文化距离同样产生显著的负面影响。在未来学校布局调整的进程中,县域教育决策者应将关注点从一味追求规模效益转移到教育公平和教育质量上来。要保证农村学生就近入学,设定上学距离的限制;促进学校间教育资源的均衡配置,保证所有学生享受同等质量的教育资源;采用科学的规划程序完善布局调整政策的实施。 展开更多
关键词 农村学校撤并 上学距离 GIS ORDINAL LOGIT 学校布局规划
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粮农综合补贴对农户种粮积极性的影响分析——以内蒙古太仆寺旗种植业农户为例 被引量:5
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作者 崔奇峰 周宁 +1 位作者 孙翠清 吴颍宣 《农业经济》 北大核心 2014年第1期69-72,共4页
为了验证粮农综合补贴政策能否影响农户生产积极性,进而影响粮食生产。本文对内蒙古太仆寺旗从事种植业生产的农户进行了问卷调查,选取在维持目前粮农综合补贴标准和发放方式不变的情况下,农户对3年后种植粮食作物表达出的意愿和态度这... 为了验证粮农综合补贴政策能否影响农户生产积极性,进而影响粮食生产。本文对内蒙古太仆寺旗从事种植业生产的农户进行了问卷调查,选取在维持目前粮农综合补贴标准和发放方式不变的情况下,农户对3年后种植粮食作物表达出的意愿和态度这一微观视角进行研究。Ordinal回归模型拟合结果及相关统计分析表明,由于补贴占收入比重较小,以种粮为主农户的收入远低于外出打工和兼业农户的收入水平,因此,补贴对未来农户种粮积极性的增加没有起到激励作用,反而是目前获得补贴较高的被调研农户,未来不愿意种粮的倾向性更高,长期发展我国种粮的有效劳动力可能更加缺乏。为此,本文提出在稳定现有补贴政策的基础上,鼓励规模化种粮,提高种粮农户的收益,以及在WTO规则允许范围内实施与粮食播种面积挂钩的补贴并提高补贴标准,进而提高农户生产积极性的政策建议。 展开更多
关键词 粮农综合补贴 种粮积极性 ordinal模型
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基层农技人员对农业科技入户工程的价值认同及其影响因素分析 被引量:3
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作者 朱烨 吴贤荣 张俊飚 《科技管理研究》 CSSCI 北大核心 2014年第18期31-35,共5页
基层农技人员对农业科技入户工程的价值认同是影响农业技术推广效率的关键因素。调查湖北省378位基层农技人员对农业科技入户工程的价值认同情况,并用Ordinal模型对影响其价值认同的因素进行实证分析。研究结果表明:第一,基层农技人员... 基层农技人员对农业科技入户工程的价值认同是影响农业技术推广效率的关键因素。调查湖北省378位基层农技人员对农业科技入户工程的价值认同情况,并用Ordinal模型对影响其价值认同的因素进行实证分析。研究结果表明:第一,基层农技人员对农业科技入户工程的价值认同程度不高;第二,文化程度、月收入、地方政府对农业推广的重视程度、对科技政策的了解程度等变量是影响基层农技人员对农业科技入户认同程度的关键因素。 展开更多
关键词 农业科技入户工程 基层农技人员 Ordinal回归模型 价值认同 影响因素
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Vegetation-environment relationships in the forests of Chitral district Hindukush range of Pakistan 被引量:8
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作者 Nasrullah Khan Syed Shahid Shaukat +1 位作者 Moinuddin Ahmed Muhammad Faheem Siddiqui 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期205-216,共12页
We investigated the composition of plant communities to quantify their relationships with environmental parameters in the Chitral Hindukush range of Pakistan. We sampled tree vegetation using the Point Centered Quarte... We investigated the composition of plant communities to quantify their relationships with environmental parameters in the Chitral Hindukush range of Pakistan. We sampled tree vegetation using the Point Centered Quarter (PCQ) method while understory vegetation was sampled in 1.5-m circular quadrats. Cedrus deodara is the national symbol of Pakistan and was dominant in the sampled communities. Because environmental variables determine vegetation types, we analyzed and evaluated edaphic and topographic factors. DCA-Ordination showed the major gradient as an amalgam of elevation (p<0.05) and slope (p<0.01) as the topographic factors correlated with species distribution. Soil variables were the factors of environmental significance along DCA axes. However, among these factors, Mg2+ , K + and N2+ contributed not more than 0.054% 0.20% and 0.073%, respectively, to variation along the first ordination axis. We conclude that the principal reason for weak or no correlation with many edaphic variables was the anthropogenic disturbance of vegetation. The understory vegetation was composed of perennial herbs in most communities and was most dense under the tree canopy. The understory vegetation strongly regulates tree seedling growth and regeneration patterns. We recommend further study of the understory vegetation using permanent plots to aid development of forest regeneration strategies. 展开更多
关键词 environmental relationship MULTIVARIATE ANALYSIS cluster ANALYSIS ordination ANTHROPOGENIC factors forest Hindukush RANGE
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个体特征、补偿机制与农民对新农合的满意度 被引量:29
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作者 于长永 《人口与经济》 CSSCI 北大核心 2013年第6期101-110,共10页
文章基于2012年对新疆726位农民的调查数据,利用Ordinal Logistic回归模型,实证分析个体特征、补偿机制与农民对新农合满意度的影响。结果表明:农民对新农合的满意度比较高;补偿机制总体合理性及其五个方面的合理性,显著影响农民对新农... 文章基于2012年对新疆726位农民的调查数据,利用Ordinal Logistic回归模型,实证分析个体特征、补偿机制与农民对新农合满意度的影响。结果表明:农民对新农合的满意度比较高;补偿机制总体合理性及其五个方面的合理性,显著影响农民对新农合的满意度;年龄越大、政治面貌为党(团)员、少数民族的农民,对新农合的满意度更高。农民对新农合的满意度主要取决于农民的受益水平,同时也受到新农合缴费标准合理性、服务和监督管理水平的影响。提高农民对新农合的满意度,首先要适当提高新农合补偿比例,适度扩大新农合补偿范围,合理确定农民缴费标准;同时,要简化新农合补偿手续,提高补偿的便利性,加强监督管理,促进补偿的公平性。 展开更多
关键词 新型农村合作医疗 补偿机制 满意度 ORDINAL LOGISTIC回归模型
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