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Research on Precise Trigonometric Leveling in Place of First Order Leveling 被引量:7
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作者 ZHANG Zhenglu ZHANG Kun +1 位作者 DENG Yong LUO Changlin 《Geo-Spatial Information Science》 2005年第4期235-239,共5页
Through the analysis of the principle, error sources and precision of trigonometric leveling, this paper points out the key problems about first order leveling replaced by trigonometric leveling; and for the first tim... Through the analysis of the principle, error sources and precision of trigonometric leveling, this paper points out the key problems about first order leveling replaced by trigonometric leveling; and for the first time puts forward that, in some given conditions, it is not only feasible but also valuable to replace first order leveling by precise trigonometric leveling, and proves it by experimentation as well. The content and conclusion of this paper have consulting significance and practicable value for our setting down relational criterion and production practice. 展开更多
关键词 electronic distance measurements trigonometric leveling first order leveling surveying for deformation monitoring
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Higher-Order Level-Set Method and Its Application in Biomolecular Surfaces Construction 被引量:2
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作者 Chandrajit L. Bajaj 徐国良 张琴 《Journal of Computer Science & Technology》 SCIE EI CSCD 2008年第6期1026-1036,共11页
We present a general framework for a higher-order spline level-set (HLS) method and apply this to biomolecule surfaces construction. Starting from a first order energy functional, we obtain a general level set formu... We present a general framework for a higher-order spline level-set (HLS) method and apply this to biomolecule surfaces construction. Starting from a first order energy functional, we obtain a general level set formulation of geometric partial differential equation, and provide an efficient approach to solving this partial differential equation using a C2 spline basis. We also present a fast cubic spline interpolation algorithm based on convolution and the Z-transform, which exploits the local relationship of interpolatory cubic spline coefficients with respect to given function data values. One example of our HLS method is demonstrated their individual atomic coordinates which is the construction of biomolecule and solvated radii as prerequisites. surfaces (an implicit solvation interface) with 展开更多
关键词 higher-order spline level-set geometric partial differential equation biomolecular surface
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Higher-Order Squeezing for Atomic Dipole of a Three-Level Atom in the Kerr-Like Medium Cavity Fields
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作者 卢俊 许毅 董传华 《Journal of Shanghai University(English Edition)》 CAS 2003年第1期49-54,共6页
In this paper, evolution of the higher order squeezing for atomic dipole of three level atom in the Kerr like medium is investigated. The atom discussed has two configurations and is driven by the single mode cohe... In this paper, evolution of the higher order squeezing for atomic dipole of three level atom in the Kerr like medium is investigated. The atom discussed has two configurations and is driven by the single mode coherent state field. Our results show that the squeezing effects are clearly influenced by nonlinear parameters, the initial atom state and the detuning. 展开更多
关键词 J C model higher order squeezing three level atom atomic dipole moment.
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Ordering and Pricing Strategies for Fresh Products with Multiple Quality Levels Considering Consumer Utility
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作者 Peiqi Ma 《American Journal of Operations Research》 2015年第3期192-198,共7页
In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantit... In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantity. Our results showed that, facing the two quality levels of fresh products, retailers would not benefit from sales of lower quality of fresh products with the deterministic demand. In the pursuit of profit maximization, the initial order quantity is smaller than the potential demand for market. 展开更多
关键词 FRESH Products CONSUMER UTILITY MULTIPLE Quality level PRICING and orderING
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Multi-level effects in the high-order harmonic generation driven by intense frequency-comb laser fields
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作者 赵迪 蒋臣威 李福利 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期256-261,共6页
High harmonic generation(HHG) driven by intense frequency-comb laser fields can be dramatically enhanced via multiphoton resonance by tuning the carrier-envelope phase(CEP) shift, without increasing the driving in... High harmonic generation(HHG) driven by intense frequency-comb laser fields can be dramatically enhanced via multiphoton resonance by tuning the carrier-envelope phase(CEP) shift, without increasing the driving intensity. However,the multiphoton-resonant enhancement(MRE) factor in the realistic atomic hydrogen is much smaller than that in a twolevel system. To study the deviation, we present a theoretical investigation of the multiphoton resonance dynamics of three-level systems driven by intense frequency-comb laser fields. The many-mode Floquet theorem(MMFT) is employed to provide a nonperturbative and exact treatment of the interaction between the quantum system and the laser fields. The investigations show that the dipole interaction of a two-level system with the third level affects the multiphoton resonance dynamics and enhances the HHG spectra. It is the dipole interaction of the excited level of the two-level system with other levels that results in the smaller MRE factor in the realistic atomic system. 展开更多
关键词 high-order harmonic generation frequency-comb laser fields multi-level effects
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基于Ordered Probit模型的区域客运通道需求层次识别 被引量:1
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作者 李莉 丁宏飞 《重庆交通大学学报(自然科学版)》 CAS 北大核心 2014年第5期124-127,共4页
为保证区域客运通道运力资源的合理配置,选取客运需求层次为因变量,个人收入、出行目的、心理偏好为控制变量,建立了客运需求层次识别的Ordered Probit模型。根据成渝客运通道的相关调查数据,利用Stata软件的oprobit命令实现参数估计,... 为保证区域客运通道运力资源的合理配置,选取客运需求层次为因变量,个人收入、出行目的、心理偏好为控制变量,建立了客运需求层次识别的Ordered Probit模型。根据成渝客运通道的相关调查数据,利用Stata软件的oprobit命令实现参数估计,并借助MATLAB软件的插值技术,描绘出该通道内控制变量对因变量的作用效果变化特征三维图。结果表明:此需求层次识别模型可以良好的表征不同影响因素下旅客的需求层级。 展开更多
关键词 交通运输 区域客运通道 orderED PROBIT模型 需求层次
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Two-level stabilized finite element method for Stokes eigenvalue problem 被引量:1
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作者 黄鹏展 何银年 冯新龙 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期621-630,共10页
A two-level stabilized finite element method for the Stokes eigenvalue problem based on the local Gauss integration is considered. This method involves solving a Stokes eigenvalue problem on a coarse mesh with mesh si... A two-level stabilized finite element method for the Stokes eigenvalue problem based on the local Gauss integration is considered. This method involves solving a Stokes eigenvalue problem on a coarse mesh with mesh size H and a Stokes problem on a fine mesh with mesh size h -- O(H2), which can still maintain the asymptotically optimal accuracy. It provides an approximate solution with the convergence rate of the same order as the usual stabilized finite element solution, which involves solving a Stokes eigenvalue problem on a fine mesh with mesh size h. Hence, the two-level stabilized finite element method can save a large amount of computational time. Moreover, numerical tests confirm the theoretical results of the present method. 展开更多
关键词 Stokes eigenvalue problem stabilized method lowest equal-order pair two-level method
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Fuzzy Ordered Filters in Implicative Semigroups
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作者 库热西 黄文平 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期53-57, ,共5页
We fuzzify the concept of ordered filter in implicative negatively partially ordered semigroups and study its properties.
关键词 implicative) negatively partially ordered semigroup ordered filter fuzzy ordered filter level ordered filter
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A Generalized Information Criterion for Parameters under an Umbrella Order Restriction
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作者 宋海燕 陶剑 史宁中 《Northeastern Mathematical Journal》 CSCD 2005年第2期127-130,共4页
The detection of the configuration of parameters is one of the most important problems in statistical studies. It is well known that the Akaike’s information criterion (AIC) is a key tool for this problem
关键词 umbrella ordering level probability AIC criterion ORIC criterion
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TD-SCDMA/GSM/GPRS双模终端CELL CHANGE ORDER过程研究
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作者 田煚升 李贵勇 《电子测试》 2010年第10期36-42,共7页
随着TD-SCDMA系统的商用,同时需兼容已非常成熟运营的GSM系统,TD-SCDMA/GSM/GPRS双模终端已是市场的主流。本文针对双模单待终端(协议控制)CELL CHANGE ORDER过程进行研究,该过程是双模终端实现PS域切换的一种重要方式。首先,以TD-SCDMA... 随着TD-SCDMA系统的商用,同时需兼容已非常成熟运营的GSM系统,TD-SCDMA/GSM/GPRS双模终端已是市场的主流。本文针对双模单待终端(协议控制)CELL CHANGE ORDER过程进行研究,该过程是双模终端实现PS域切换的一种重要方式。首先,以TD-SCDMA/GSM/GPRS系统高层协议为基础介绍了双模单待自动切换终端的CELL CHANGE ORDER过程的各个阶段:系统间测量、网络判决及小区改变执行;然后详细地设计了小区改变执行的正常及异常处理流程,并对如何实现数据平面切换过程进行了重点描述;最后搭建板级测试环境,进行协议一致性测试,验证了CELL CHANGE ORDER过程的实现。 展开更多
关键词 双模终端 协议栈 CELL CHANGE order 数据平面 板级测试
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Improving Laboratory Test-Ordering with Information Technology
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作者 Adnan Ali Baddour Anas Serag Dablool Saeed Saeed Al-Ghamdi 《International Journal of Clinical Medicine》 2012年第6期446-458,共13页
The overuse of clinical laboratory services has been documented for many years. This overuse use does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. The utilizatio... The overuse of clinical laboratory services has been documented for many years. This overuse use does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. The utilization of diagnostic laboratories has increased over the last decade around the world. This increased laboratory use is appropriate if it allows accurate diagnoses to be made, ideal treatment to be identified and monitored, accurate prognoses to be established, and patients’ hospital stays to be shortened. Thus, improving the appropriateness of testing behavior and reducing the number of laboratory tests have been recognized as essential parts of quality improvement program. In this study, the effectiveness of a computer-based system in improving the laboratory test-ordering in a general hospital was investigated. The study was conducted through four stages, the preparation stage, the pre-intervention stage, the post-intervention 1) stage and post-intervention 2) stage. Guideline and computer system were developed during preparation stage. Medical records were reviewed against guideline recommendations before any intervention during the pre-intervention stage, after guideline dissemination through educational workshops during the post intervention 1) stage, and after implementation of the computer system with the new requesting form during the post intervention 2) stage. The study revealed that the computer-based system achieved a statistically significant increase in the percentage of appropriate use from 44.6% in the post-intervention 1) stage to 55.6%, and a statistically significant increase in the compliance with guideline by prescriber as well as increased in guideline conformity rate from 16.7% in the post-intervention 1) stage to 32.5% in the post-intervention 2) stage, and decreased in the percentage of prescribers whose level was unsatisfactory from 85.4% the post-intervention 1) stage to 66.7% in the post-intervention 2) stage. 展开更多
关键词 Computer-Based System LABORATORY Test-ordering GUIDELINE CONFORMITY RATE COMPLIANCE level
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智慧农业发展水平系统协同度评价研究 被引量:1
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作者 陈红川 张艳 +1 位作者 黄小军 刘春贞 《现代农业》 2025年第1期17-25,57,共10页
智慧农业作为现代农业发展的主攻方向,其发展对推动农业现代化的整体跃迁和农业可持续发挥至关重要的作用。文章将复合系统协同度模型和莫兰指数作为分析工具,以2018—2022年我国29个省区市(除上海市、西藏自治区和港澳台地区)为研究对... 智慧农业作为现代农业发展的主攻方向,其发展对推动农业现代化的整体跃迁和农业可持续发挥至关重要的作用。文章将复合系统协同度模型和莫兰指数作为分析工具,以2018—2022年我国29个省区市(除上海市、西藏自治区和港澳台地区)为研究对象,从农业机械化和生产要素配置水平、农业产出水平、农业科技创新水平和农业发展环境支撑水平4个子系统维度评价智慧农业发展水平系统协同度。结果表明:2018—2022年我国智慧农业发展水平协同度均值仅为0.23,数值偏低,且存在显著的区域差异;2018—2022年我国智慧农业机械化和生产要素配置水平子系统、农业产出水平子系统、农业科技创新水平子系统和农业发展环境支撑水平子系统发展水平有序度均值分别为0.51、0.53、0.42、0.36,其中智慧农业发展环境支撑水平子系统有序度均值最低。目前,我国智慧农业发展水平目前不存在显著的空间正相关性。根据研究结果提出发展建议,为我国智慧农业发展提供参考。 展开更多
关键词 智慧农业 发展水平 协同度 有序度 莫兰指数
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An Approach to Fault Diagnosis of Rotating Machinery Using the Second-Order Statistical Features of Thermal Images and Simplified Fuzzy ARTMAP
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作者 Faisal Al Thobiani Van Tung Tran Tiedo Tinga 《Engineering(科研)》 2017年第6期524-539,共16页
Thermal image, or thermogram, becomes a new type of signal for machine condition monitoring and fault diagnosis due to the capability to display real-time temperature distribution and possibility to indicate the mach... Thermal image, or thermogram, becomes a new type of signal for machine condition monitoring and fault diagnosis due to the capability to display real-time temperature distribution and possibility to indicate the machine’s operating condition through its temperature. In this paper, an investigation of using the second-order statistical features of thermogram in association with minimum redundancy maximum relevance (mRMR) feature selection and simplified fuzzy ARTMAP (SFAM) classification is conducted for rotating machinery fault diagnosis. The thermograms of different machine conditions are firstly preprocessed for improving the image contrast, removing noise, and cropping to obtain the regions of interest (ROIs). Then, an enhanced algorithm based on bi-dimensional empirical mode decomposition is implemented to further increase the quality of ROIs before the second-order statistical features are extracted from their gray-level co-occurrence matrix (GLCM). The highly relevant features to the machine condition are selected from the total feature set by mRMR and are fed into SFAM to accomplish the fault diagnosis. In order to verify this investigation, the thermograms acquired from different conditions of a fault simulator including normal, misalignment, faulty bearing, and mass unbalance are used. This investigation also provides a comparative study of SFAM and other traditional methods such as back-propagation and probabilistic neural networks. The results show that the second-order statistical features used in this framework can provide a plausible accuracy in fault diagnosis of rotating machinery. 展开更多
关键词 Thermal Images SECOND-order Statistical Features Gray-level CO-OCCURRENCE Matrix Minimum REDUNDANCY Maximum Relevance Rotating Machinery Fault Diagnosis Simplified Fuzzy ARTMAP
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基于改进前景理论的物流服务供应链订单公平分配研究 被引量:1
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作者 李壮阔 裴婕妤 《供应链管理》 2025年第3期68-82,共15页
文章基于改进前景理论,引入考虑公平性的效用函数模型,同时考虑物流服务质量水平、物流服务集成商与供应商之间公平性、供应商与供应商之间公平性,构建数学模型,优化供应链内的订单分配机制。通过数学建模与数值分析发现:物流服务订单... 文章基于改进前景理论,引入考虑公平性的效用函数模型,同时考虑物流服务质量水平、物流服务集成商与供应商之间公平性、供应商与供应商之间公平性,构建数学模型,优化供应链内的订单分配机制。通过数学建模与数值分析发现:物流服务订单数量受物流服务供应商的销售价格与缺陷率影响,降低供应商的物流服务销售价格和缺陷率,提高物流服务质量水平的边际系数,在一定阈值内可以有效增加订单数额,从而提升物流服务集成商和供应商的利润。文章所建模型体现了公平性原则,使多数参与主体在合作过程中感受到显著公平待遇,这对于提升供应链稳定性和整体效用具有正向价值。 展开更多
关键词 物流服务供应链 订单分配 服务质量水平 公平关切 前景理论
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互嵌性秩序博弈:基层社会冲突根源及其阻力探微——基于反向秩序的视角
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作者 胡锐军 《西安交通大学学报(社会科学版)》 北大核心 2025年第5期163-171,共9页
社会冲突是决定社会变迁、解释社会运动的关键和核心密码。作为社会稳定压舱石的县域,其社会冲突治理水平对基层稳定起着不可或缺的作用。由于秩序与冲突形影相随,从正向秩序描摹来思考秩序建构和社会冲突治理问题形成了不同的技术路径... 社会冲突是决定社会变迁、解释社会运动的关键和核心密码。作为社会稳定压舱石的县域,其社会冲突治理水平对基层稳定起着不可或缺的作用。由于秩序与冲突形影相随,从正向秩序描摹来思考秩序建构和社会冲突治理问题形成了不同的技术路径或逻辑理路,冲突论也由此与功能论、互动论一起构成了分析社会秩序演变的三大理论范式。而从发生学的反向秩序视野看,社会冲突演变与社会秩序变迁的交互特性决定了基层治理现代化的过程就是新旧秩序的较量更迭过程,秩序变迁的平顺、平稳性水平直接决定了风险的程度。从反向秩序角度分析社会冲突的触发根源及其表现形式成为一种可能和新路径。在推进中国式现代化的进程中,治理秩序的变迁必然持续经历新旧秩序的较量。新旧秩序在破立存废的互斥互融交互关系中互嵌博弈,主要体现在建构秩序与自发秩序、乡村秩序与城镇秩序、差序秩序与平等秩序、礼治秩序与法治秩序、封闭秩序与开放秩序、内向秩序与外向秩序等对举秩序的互嵌,其博弈结果会自动投射和映衬到社会风险源中,由此构成现代秩序变迁的阻力和社会冲突风险的重要来源。 展开更多
关键词 中国式现代化 基层社会治理 县域治理秩序 社会冲突 社会秩序 秩序互嵌博弈 发生学 反向秩序
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基于多级分数阶微积分的地震数据解释性高分辨率处理方法
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作者 高利君 李海英 +2 位作者 杨威 龚伟 李卿卿 《世界核地质科学》 2025年第3期552-564,共13页
在地震勘探中,高分辨率地震反射成像数据体是实现沉积盆地薄层砂体和断裂构造精细识别的关键手段。而实际地震成像剖面往往面临低频与高频信号缺失,进而导致地震成像分辨率低,无法有效实现油气及铀煤等矿产资源的有效识别。在信号处理中... 在地震勘探中,高分辨率地震反射成像数据体是实现沉积盆地薄层砂体和断裂构造精细识别的关键手段。而实际地震成像剖面往往面临低频与高频信号缺失,进而导致地震成像分辨率低,无法有效实现油气及铀煤等矿产资源的有效识别。在信号处理中,有效信号的积分及微分算法分别反应其低频和高频成分。基于此原理,提出一种基于多级分数阶微积分方法的解释性高分辨率处理方法。通过分别计算有效信号的不同分数阶成分,获得地震成像剖面中缺失的低频及高频成分,通过引入多元高斯理论与贝叶斯理论,以及统计学反演改进加权系数的求解过程,建立了宽频高分辨率地震成像剖面。与传统微积分高分辨率处理方法相比,本方法能有效提高加权系数的求解准确性,并且有效避免了加权系数计算误差对精度的影响。陆上及海上实际数据处理结果表明,本方法能够有效提升地震数据的分辨率和频带范围,提高地震成像对砂体等构造的高分辨率识别。 展开更多
关键词 多元高斯 多级分数阶微积分 高分辨率 地震数据
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两类绿地中人工栽植火炬树横走侧根特点研究
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作者 张怡然 阿地力·沙塔尔 +1 位作者 叶尔江·拜克吐尔汉 徐栋 《植物科学学报》 北大核心 2025年第4期532-540,共9页
火炬树(Rhus typhina L.)水平根系极其发达,在适宜条件下极易大肆扩散蔓延,使本地植物失去生存空间。本文以两类绿地中人工栽植的火炬树为研究对象,采用挖根的方式进行调查,利用描述性统计、方差分析、t检验等方法,分析生境水平相似、... 火炬树(Rhus typhina L.)水平根系极其发达,在适宜条件下极易大肆扩散蔓延,使本地植物失去生存空间。本文以两类绿地中人工栽植的火炬树为研究对象,采用挖根的方式进行调查,利用描述性统计、方差分析、t检验等方法,分析生境水平相似、管理措施相同的火炬树横走侧根的特点。结果显示,火炬树仅有少数较细的垂直根系,无明显垂直主根,主要分布在20 cm土层以内,属于水平根型和浅根型;4个方向中的两个方向根系分布相对密集;火炬树根系直径、生物量随序级的升高而升高,但数量、根系长度与之相反,乌鲁木齐样地中≤1 mm的根系显著多于库尔勒样地(P<0.05);火炬树繁殖根的分支强度与节间长度呈正相关,与垂直角度呈负相关,繁殖根的其他特征之间相关性不显著。 展开更多
关键词 火炬树 横走侧根 根系构型 繁殖根 各级根序 细根
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空间流动与秩序更替:城市社区公共文化空间序变能力研究
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作者 穆晨 《文化产业研究》 2025年第2期44-56,共13页
高秩序水平不是城市社区公共文化空间追求的终极形态,高序变能力才是其优化的重要标志。空间流动虽然导致城市社区公共文化空间面临秩序更替下新的社区治理问题,但同时也促使其向更符合文化多元性、更能消化社会系统压力的状态演化。过... 高秩序水平不是城市社区公共文化空间追求的终极形态,高序变能力才是其优化的重要标志。空间流动虽然导致城市社区公共文化空间面临秩序更替下新的社区治理问题,但同时也促使其向更符合文化多元性、更能消化社会系统压力的状态演化。过分关注城市社区公共文化空间的秩序水平而非序变能力,可能导致短期治理措施打断长周期的文化空间序变过程。城市社区公共文化空间的序变能力生成主要依靠“分散—联结”的凝聚性动力机制、“侵入—调和”的超越性动力机制与“固化—重构”的延续性动力机制。城市社区公共文化空间序变能力研究的核心在于社区公共性重塑与文化多元化发展是否相对平衡,社区内部空间与社区外部空间的张力是否相对合理等。 展开更多
关键词 秩序水平 序变能力 空间流动 空间演化
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风电场风机基础沉降监测结果分析
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作者 宋健 曲长啸 +1 位作者 陈明珍 王力轲 《地矿测绘》 2025年第3期63-66,98,共5页
以某风电场风机基础为研究对象,旨在通过沉降监测保障风电机组安全运行并验证基础设计施工质量。采用二等水准测量法,合理布设观测点与基准点形成水准环线,运用高精度水准仪定期往返测量获取高程数据,经统计分析沉降量、平均沉降及基础... 以某风电场风机基础为研究对象,旨在通过沉降监测保障风电机组安全运行并验证基础设计施工质量。采用二等水准测量法,合理布设观测点与基准点形成水准环线,运用高精度水准仪定期往返测量获取高程数据,经统计分析沉降量、平均沉降及基础倾斜值,绘制时间-沉降量曲线。结果表明,该监测体系可及时发现基础微小沉降与潜在风险,当沉降超限时能有效预警,为维护措施提供数据支撑,成功降低机组沉降、倾斜及倒塌风险。研究证实了风机基础设计施工的合理性,为风电场安全稳定运营提供保障,其监测方法与经验可为后续风电场建设运营提供参考,助力提升经济效益与社会效益。 展开更多
关键词 风电场 风机基础 沉降监测 二等水准观测
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现代测绘基准体系测量标志点选埋与维护策略研究
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作者 李宝 胡振发 魏灵辉 《安徽地质》 2025年第3期268-272,共5页
构成现代测绘基准的各类测量标志是国家重要的测量基础设施。安徽省现代测绘基准体系建设,旨在全面分析上一代C级GNSS点、三等水准点建设及踏勘现状,结合具体布设与选点方案,研究点位维护及选埋方案,制定详细的选点要求、埋石规格及维... 构成现代测绘基准的各类测量标志是国家重要的测量基础设施。安徽省现代测绘基准体系建设,旨在全面分析上一代C级GNSS点、三等水准点建设及踏勘现状,结合具体布设与选点方案,研究点位维护及选埋方案,制定详细的选点要求、埋石规格及维护标准,形成理论化、流程化、规格化的研究结果,为大地控制网数据观测等测绘活动奠定坚实的测量起算基础。本文通过实际验证,研究的测量标志选埋与维护策略符合测量保护及观测要求,对现代测绘基准改造升级起到规范化、标准化作用。 展开更多
关键词 现代测绘基准 GNSS点 三等水准点 点位选埋 点位维护
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