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GEOMETRIC CONSTRUCTION OF ASSOCIATION SCHEMES FROM DEGENERATE QUADRICS INPROJECTIVE SPACES PG(2ν+δ+ι-1, Fq) FOR q ODD 被引量:1
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作者 王恺顺 魏鸿增 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期35-43,共9页
Let Fq be a finite field with q elements, where q is a power of an odd prime,In this paperl the authors consider a projective space PG(2v + δ + l, Fq) with dimension 2v + δ + l, partitioned into an affine space AG(2... Let Fq be a finite field with q elements, where q is a power of an odd prime,In this paperl the authors consider a projective space PG(2v + δ + l, Fq) with dimension 2v + δ + l, partitioned into an affine space AG(2v + δ + l, Fq) of dimension 2v + δ + l and a hyperplane H = PG(2v + δ + l - 1, Fq) of dimension 2v + δ + l - 1 at infinity, where l ≠0.The points of the hyperplane H are next partitioned into four subsets. A pair of points a and b of the affine space is defined to belong to class i if the line ab meets the subsct i of H. Finally, a family of four-class association schemes are constructed, and parameters are also computed. 展开更多
关键词 projective space QUADRIC association scheme
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Design of Water Disinfection Scheme for Rural Drinking Water Safety Project 被引量:1
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作者 Qing Lu 《Meteorological and Environmental Research》 CAS 2013年第7期28-31,共4页
As further promotion of the rural drinking water safety project in whole country, small villages in vast countryside have been or will be equipped with safety drinking water project. We analyzed necessity of the rural... As further promotion of the rural drinking water safety project in whole country, small villages in vast countryside have been or will be equipped with safety drinking water project. We analyzed necessity of the rural drinking water disinfection, discussed disinfection method suitable for rural drinking water characteristics, and put forward disinfection schemes for different water supply sources. 展开更多
关键词 Rural drinking water safety project Disinfection method Disinfection scheme China
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Superconvergence of nonconforming finite element penalty scheme for Stokes problem using L^2 projection method 被引量:3
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作者 石东洋 裴丽芳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第7期861-874,共14页
A modified penalty scheme is discussed for solving the Stokes problem with the Crouzeix-Raviart type nonconforming linear triangular finite element. By the L^2 projection method, the superconvergence results for the v... A modified penalty scheme is discussed for solving the Stokes problem with the Crouzeix-Raviart type nonconforming linear triangular finite element. By the L^2 projection method, the superconvergence results for the velocity and pressure are obtained with a penalty parameter larger than that of the classical penalty scheme. The numerical experiments are carried out to confirm the theoretical results. 展开更多
关键词 SUPERCONVERGENCE Crouzeix-Raviart type nonconforming finite element penalty scheme L^2 projection method
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Two power projects under BOT funding scheme progressing smoothly
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《Electricity》 1997年第1期48-48,共1页
关键词 BOT Two power projects under BOT funding scheme progressing smoothly
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Velocity Projection with Upwind Scheme Based on the Discontinuous Galerkin Methods for the Two Phase Flow Problem
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作者 Jiangyong Hou Wenjing Yan Jie Chen 《International Journal of Modern Nonlinear Theory and Application》 2015年第2期127-141,共15页
The upwind scheme is very important in the numerical approximation of some problems such as the convection dominated problem, the two-phase flow problem, and so on. For the fractional flow formulation of the two-phase... The upwind scheme is very important in the numerical approximation of some problems such as the convection dominated problem, the two-phase flow problem, and so on. For the fractional flow formulation of the two-phase flow problem, the Penalty Discontinuous Galerkin (PDG) methods combined with the upwind scheme are usually used to solve the phase pressure equation. In this case, unless the upwind scheme is taken into consideration in the velocity reconstruction, the local mass balance cannot hold exactly. In this paper, we present a scheme of velocity reconstruction in some H(div) spaces with considering the upwind scheme totally. Furthermore, the different ways to calculate the nonlinear coefficients may have distinct and significant effects, which have been investigated by some authors. We propose a new algorithm to obtain a more effective and stable approximation of the coefficients under the consideration of the upwind scheme. 展开更多
关键词 VELOCITY projectION UPWIND scheme PENALTY DISCONTINUOUS GALERKIN Methods Two Phase Flow in Porous Media
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Estimating minimum ecological water required of the western route first stage project of China's south-to-north water transfer scheme for water exporting rivers
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作者 MEN Bao-hui 《Journal of Environmental Science and Engineering》 2007年第1期19-24,共6页
It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin ... It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin of the Yellow River, which is mainly located in Northern China. So the western route project of south-north water transfer scheme (WRP-SNWTS) aims to transfer water from the Yangtze River to the Yellow River. The area of WRP-SNWT, located in the upper reaches of the Yangtze River and the main areas of Sichuan and the marginal areas of the Qinghai-Tibet Plateau, has sufficient water resources but fragile ecology and environment. Therefore, it is necessary for WRP-SNWT to analyze the ecology water required. Based on the planning principles of from low elevation to high elevation, from small to large, from short to long and from easy to difficulty, the WRP-SNWT will be constructed through three stage projects. The western route first stage project of the south-north water transfer scheme (WRFST-SNWTS) is planned to transfer 4×10^9m^3/a from six tributaries of the Yalong river and from Dadu river to Jiaqu of Yellow River.. Daqu river and Niqu river are the branches of Xianshui river. Sequ river, Duke river, Make river and Ake river are the branches of Dadu river, which account for 65-70% of the total river run-off. It need more research and the rest run-off can satisfy channel ecology water required. According to analysis ecological water required which mainly satisfy for aquicolous biology in water-exporting region, such as low air temperature. Fish and aquicolous biology main living from May to August, and rivers are iced up from December to March of next year, ecology water required mainly for fish and aquicolous biology. The flow criterion of Tennant method is modified. The ecology water required of WRFSP-SNWTS is estimated by the flow data of Zhuwo gauging station, Zhuba gauging station, Chuosijia gauging station and Zumuzu gauging station. The result show that the ecology water required calculated by modified Tennant less 1 l percent than that of Tennant. This estimating result can supply more water resources for transferring to Yellow River. Meanwhile, this can supply gist for research transferring water of WRFSP-SNWTS. 展开更多
关键词 Yangtze River Yellow River western route first stage project of the south-north water transfer scheme minimum ecological water required Tennant method
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Eco-environmental benefit assessment of China's South-North Water Transfer Scheme——the middle route project
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作者 DUANGuang-ming ZHAOJing-zhu LIUGuo-hua KEBing XIAOHan WUGang DENGHong-bing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期308-315,共8页
This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of ... This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT's middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13 07 billion RMB Yuan in 2010 and 19 79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors. 展开更多
关键词 China's South-North Water Transfer scheme(SNWT) the middle route project of South-North Water Transfer(MRPSNWT) assessment ecosystem services monetary indices
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多伦拜引水枢纽方案比选与工程设计
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作者 赵德亮 《黑龙江水利科技》 2026年第1期106-110,共5页
针对新疆多伦拜引水枢纽工程因长期运行导致的闸基冲刷、结构老化及防冲能力不足等问题,本文通过水文地质复核与工程现状分析,提出上下两个闸址除险加固方案进行比选。通过上、下闸址两方案的比选,综合考虑工程地质、枢纽布置、施工条... 针对新疆多伦拜引水枢纽工程因长期运行导致的闸基冲刷、结构老化及防冲能力不足等问题,本文通过水文地质复核与工程现状分析,提出上下两个闸址除险加固方案进行比选。通过上、下闸址两方案的比选,综合考虑工程地质、枢纽布置、施工条件及方案投资等因素,在地形地质及施工条件方面,上闸址与下闸址均相同;同时上闸址在枢纽布置合理性及工程投资方面优于下闸址,故推荐上闸址。引水枢纽除险加固后新建泄洪闸、进水闸及导流堤等,保障下游0.53万hm2灌区灌溉供水安全,并为类似引水枢纽除险加固工程提供技术参考。 展开更多
关键词 引水枢纽工程 除险加固 方案比选 闸堰结合
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A class of fully third-order accurate projection methods for solving the incompressible Navier-Stokes equations 被引量:2
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作者 Yuxin Ren Yuxi Jiang +1 位作者 Miao'er Liu Hanxin Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期542-549,共8页
In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We the... In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases. 展开更多
关键词 Incompressible Navier-Stokes equations projection methods - Third-order scheme - Local truncation error
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复杂艰险地区隧道工程施工方案优选决策研究
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作者 段晓晨 周龙 +2 位作者 段鹏鑫 杨晓雪 苏丹娜 《铁道工程学报》 北大核心 2025年第7期72-76,共5页
研究目的:为解决目前西南复杂艰险地区隧道工程施工方案优化中没有很好兼顾环保、安全、质量导致一系列事故问题,本文综合考虑施工工期、成本、质量、安全、环保五个施工重要指标,在网络计划技术合理划分施工活动基础上,运用模糊群方法... 研究目的:为解决目前西南复杂艰险地区隧道工程施工方案优化中没有很好兼顾环保、安全、质量导致一系列事故问题,本文综合考虑施工工期、成本、质量、安全、环保五个施工重要指标,在网络计划技术合理划分施工活动基础上,运用模糊群方法,用三角模糊数的形式表示五大指标,定义模糊多属性优属度,并利用直觉模糊集进行评价,建立综合工期-成本-质量-安全-环保的模糊优化群决策模型,并用遗传算法求得最佳作业模式组合,实现施工方案的优选决策。研究结论:(1)将模型求出的施工方案在案例隧道工程中实施,根据真实工程试验结果,在满足质量、安全、环保、工期、成本的要求基础上,工期缩短20天,成本低于预算5%,提升了工程的综合效益;(2)方法应用于隧道工程施工方案的优选决策,实现了工期、质量、成本、安全、环保等目标的均衡优化,可为隧道工程施工方案决策提供方法、数据支持和依据。 展开更多
关键词 隧道工程 模糊综合优化 遗传算法 方案优选
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Price Analysis of Water Supply for South-to-North Water Transfer Project
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作者 QIU Zhong enProfessor, Design Institute, Changjiang Water Resources Commission, Wuhan 430010, China Tan Chang liSenior Engineer, Design Institute, Changjiang Water Resources Commission, Wuhan 430010, China ZHU Qin Engineer, Design Institute, Chan 《人民长江》 北大核心 2001年第S1期29-32,共4页
The factors influencing the water supply price of a hydraulic project include natural conditions and economic policies. This paper thoroughly demonstrates the water price of South-to-North Water Transfer Project from ... The factors influencing the water supply price of a hydraulic project include natural conditions and economic policies. This paper thoroughly demonstrates the water price of South-to-North Water Transfer Project from the viewpoint of economic policies. It is considered that if the project is assigned as a profitable one and built depending on commercial loan from bank completely or mostly, the water price will be too high to be undertaken by users,and if the project places the public good at first while considering the economic benefit, its investment mainly relies on the state (national or local governments) appropriation and self-raised funds and a little from the bank loan on favorable terms, the price determined according to the principle of satisfying the cost and reasonable profit will be relatively lower and can be undertaken by the users in the North China where water shortage is serious. The problem of higher water price of agricultural irrigation to the north of the Yellow River can be tackled by taking measures such as "compensating agriculture by industry" according to foreign practical experiences and relevant suggestions. 展开更多
关键词 PRICE of WATER supply WATER PRICE estimation FUND RAISING schemes WATER TRANSFER cost Middle-Route project of South-to-North WATER TRANSFER
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基于Triangle模型的下肢静脉溃疡患者分层分级管理方案的构建及应用 被引量:1
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作者 顾飞 王娴 +2 位作者 周盼盼 周旭 王燕 《护士进修杂志》 2025年第12期1249-1257,共9页
目的构建基于Triangle模型的下肢静脉溃疡(venous leg ulcer,VLU)患者分层分级管理方案并评价其应用效果。方法于2024年1—4月采用文献回顾、小组讨论、专家会议方法构建包含低、中、高危分层标准及各级管理措施的方案,并选取于2024年5... 目的构建基于Triangle模型的下肢静脉溃疡(venous leg ulcer,VLU)患者分层分级管理方案并评价其应用效果。方法于2024年1—4月采用文献回顾、小组讨论、专家会议方法构建包含低、中、高危分层标准及各级管理措施的方案,并选取于2024年5—6月入院的36例患者为对照组,2024年7—8月入院的36例VLU患者为观察组,对照组给予患者常规治疗及护理管理措施,并为患者实施常规健康教育;观察组在对照组的基础上,实施基于Triangle模型的VLU患者分层分级管理。比较2组患者干预前、干预后溃疡面积、溃疡愈合效果、溃疡愈合总有效率、治疗依从性和自我管理能力。结果干预后,观察组的溃疡面积显著小于对照组(P<0.05)、溃疡愈合效果显著优于对照组(P<0.05);观察组的溃疡愈合总有效率为86.11%,高于对照组的63.89%,2组比较差异有统计学意义(P<0.05);观察组的治疗依从性和自我管理能力显著优于对照组(P<0.05)。结论本研究构建的基于Triangle模型的VLU患者分层分级管理方案能够为患者提供科学有效的管理,促进患者溃疡愈合,提高患者的治疗依从性和自我管理能力。 展开更多
关键词 Triangle分层分级管理模型 下肢静脉溃疡 方案构建 方案应用 护理
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基于改进灰色关联投影模型的滑坡治理方案决策研究
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作者 郑明新 卢乐意 +1 位作者 李东 阮钰华 《中国安全生产科学技术》 北大核心 2025年第5期102-110,共9页
为解决滑坡治理方案决策的多维复杂性问题,提出1种融合组合赋权与动态分辨系数的改进灰色关联投影模型。首先,构建包含滑坡地质特征认识、滑坡治理措施、经济与环境4大因素的16项决策指标,并通过分级标准实现指标定量化。然后,采用层次... 为解决滑坡治理方案决策的多维复杂性问题,提出1种融合组合赋权与动态分辨系数的改进灰色关联投影模型。首先,构建包含滑坡地质特征认识、滑坡治理措施、经济与环境4大因素的16项决策指标,并通过分级标准实现指标定量化。然后,采用层次分析法(AHP)和CRITIC分别确定主观和客观权重,基于博弈论组合赋权计算综合权重。进一步引入动态分辨系数,优化传统灰色关联投影法,提升指标区分度,最终建立滑坡治理方案决策模型。研究结果表明:改进模型具有较高的决策适用性和稳定性,稳定性提升约13.01%,优于传统模型。研究结果可为工程实践中合理选择治理措施提供更加精准的决策支持。 展开更多
关键词 滑坡治理 方案决策 组合赋权 分辨系数 灰色关联投影法
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建设工程设计方案数字化审查技术与应用研究 被引量:1
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作者 李佳雪 王履华 +1 位作者 郑光辉 沈健 《自然资源信息化》 2025年第2期19-24,共6页
审查技术是实施“多规合一”的关键支撑技术。为了提升建设工程设计方案数字化审查的效率和准确性,本文基于规则引擎、空间数据管理、多CAD平台适配等技术,设计了审查规则可扩展、具备跨CAD平台能力的快速数字化审查技术路线,并研发了... 审查技术是实施“多规合一”的关键支撑技术。为了提升建设工程设计方案数字化审查的效率和准确性,本文基于规则引擎、空间数据管理、多CAD平台适配等技术,设计了审查规则可扩展、具备跨CAD平台能力的快速数字化审查技术路线,并研发了建设工程设计方案数字化审查系统。该系统利用数字化技术,对建设工程设计方案进行编制、标准化、审查,提供建设工程设计方案编制、审查、入库一体化等功能,并在开发环境实现了建设工程设计方案辅助编制、图形质检、成果检查、成果入库等流程,验证了技术路线的可行性,为建设工程设计方案的数字化审查提供了有效的技术支持。 展开更多
关键词 国土空间规划 建设工程 设计方案 规则引擎 适配器模式 数字化审查
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新时期建设工程规划许可制度面临的困境与创新探索
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作者 郭晓林 王雯锦 +2 位作者 于连莉 周琳 邱宁 《规划师》 北大核心 2025年第12期80-87,共8页
当前,国家层面的规划许可管理职责已统一纳入国土空间用途管制制度,在此框架下探索建设工程规划许可制度设计,对满足地方规划实施管理需求具有重要意义。通过系统梳理建设工程规划许可制度的发展历程,从许可事权、许可程序、建设工程设... 当前,国家层面的规划许可管理职责已统一纳入国土空间用途管制制度,在此框架下探索建设工程规划许可制度设计,对满足地方规划实施管理需求具有重要意义。通过系统梳理建设工程规划许可制度的发展历程,从许可事权、许可程序、建设工程设计方案编制审查技术及实施监管4个维度剖析现行制度面临的困境,进而提出用途管制制度背景下的建设工程规划许可制度设计,包括细化许可事权边界与许可内容,优化设计方案审查机制与特殊程序管理,规范设计方案编制与审查尺度,强化规划核实、土地核验与不动产登记业务的衔接,完善监管机制,构建全流程闭环管理体系等,以改善营商环境、提升治理效能。 展开更多
关键词 用途管制 建设工程规划许可 设计方案 制度设计
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宝鹏通道简上路—龙景立交段方案优化
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作者 郝强 《天津建设科技》 2025年第1期23-25,62,共4页
以实际工程为案例,分析了大型工程如何在复杂建设条件下,考虑各方诉求,并保证项目技术标准和功能的前提下,从多个角度优化方案,从而节省工程投资。
关键词 大型工程 方案优化 立交
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横沙南围泵闸方案比选及结构设计
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作者 王彬 《海河水利》 2025年第10期41-45,共5页
泵闸为防洪调度和排涝减灾的关键工程,水闸和泵站的布置、选型对工程的质量和效益都格外重要,泵闸选址合理和优化总体布置对改善区域水环境以及提高整体排水除涝和蓄滞洪水的能力具有显著影响。为开展城镇排涝泵闸的设计工作,以横沙南... 泵闸为防洪调度和排涝减灾的关键工程,水闸和泵站的布置、选型对工程的质量和效益都格外重要,泵闸选址合理和优化总体布置对改善区域水环境以及提高整体排水除涝和蓄滞洪水的能力具有显著影响。为开展城镇排涝泵闸的设计工作,以横沙南围泵闸为例,对工程选址、水泵类型、建筑物选型、管理房布置方式等进行方案比选,并进行结构设计和稳定计算,提出了泵闸工程施工的研究思路及方法,研究成果可为类似工程提供参考。 展开更多
关键词 横沙南围泵站 泵闸工程 方案比选 结构设计
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三门县健跳塘提升改造工程海塘建设方案研究
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作者 邹战军 《云南水力发电》 2025年第9期145-148,180,共5页
三门县健跳塘已按50年一遇防潮标准建成,海塘塘身为混合式土石结构,迎潮面镇压层以上塘身采用混凝土护面,现状健跳塘存在塘身型式单一、沿岸环境较为杂乱、沿线局部垃圾堆积等问题,需对海塘进行提升改造。文章在分析海塘现状及问题的基... 三门县健跳塘已按50年一遇防潮标准建成,海塘塘身为混合式土石结构,迎潮面镇压层以上塘身采用混凝土护面,现状健跳塘存在塘身型式单一、沿岸环境较为杂乱、沿线局部垃圾堆积等问题,需对海塘进行提升改造。文章在分析海塘现状及问题的基础上,进行海塘建设方案研究,主要包括海塘选址、选线、海塘提升改造选型,以及海塘总体布置方案、地基处理方式、海塘整体稳定性等。 展开更多
关键词 健跳塘提升改造 方案比选 总体布置 工程设计 稳定计算
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武汉市规划方案审查智慧决策系统设计与实现
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作者 鲁俊杰 谭仁春 +2 位作者 丁晓 杨晔轩 付饶 《地理空间信息》 2025年第11期128-132,共5页
规划方案审查作为办理建设工程规划许可的核心技术审查环节,具有审查内容复杂、专业性强等特点,对城市规划管理具有重要意义。为统一审查标准、提升审查效率、提高审查智慧化水平,武汉市自然资源和城乡建设局开展了规划方案审查智慧决... 规划方案审查作为办理建设工程规划许可的核心技术审查环节,具有审查内容复杂、专业性强等特点,对城市规划管理具有重要意义。为统一审查标准、提升审查效率、提高审查智慧化水平,武汉市自然资源和城乡建设局开展了规划方案审查智慧决策系统的建设与研究。通过梳理标准化审查要点,融合CAD图纸智能解析、GIS二三维一体化空间分析和大模型技术,开发了包含图纸规整工具、网上申报模块和智慧审查模块的智慧决策系统,并应用于实际项目中。该系统建设对探索智慧审查模式,提升武汉市规划方案审查效率与服务水平具有重要意义。 展开更多
关键词 建设工程 规划方案 智慧审查 三维
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甜水堡调蓄引水工程施工方案分析
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作者 刘红娟 《云南水力发电》 2025年第4期128-130,共3页
为更好地组织和开展工程施工,文章在分析甜水堡调蓄引水项目工程区交通、供电、供水及天然建主材料等施工条件的基础上,对工程施工的重点难点进行分析,并提出相应的解决措施,进一步对施工导流、坝体填筑、放空管以及库区开挖施工等施工... 为更好地组织和开展工程施工,文章在分析甜水堡调蓄引水项目工程区交通、供电、供水及天然建主材料等施工条件的基础上,对工程施工的重点难点进行分析,并提出相应的解决措施,进一步对施工导流、坝体填筑、放空管以及库区开挖施工等施工方案进行论述探讨。 展开更多
关键词 甜水堡 调蓄 引水工程 施工方案
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